View BD90541MUV-C_9001459.PDF datasheet online --- IC-ON-LINE

Datasheet File OCR Text:

product structure : silicon monolithic integrated circuit this product has no designed protec tion against radioactive rays 1/36 tsz02201-0j3j0al01140-1-2 ? 2016 rohm co., ltd. all rights reserved. 26.apr.2016 rev.001 www.rohm.co.jp tsz22111 ? 14 ? 001 secondary power supply series for automotive 2.6v to 5.5v, 4a, 0.3mhz to 2.4mhz synchronous step-down converter BD90541MUV-C general description the BD90541MUV-C is a synchronous step-down converter which operates in current mode. it can operate with maximum frequency of 2.4 mhz, and can downsize external parts such as inductor. it can supply a maximum output current of 4a with built-in pch and nch output mosfet. output voltage and oscillation frequency can be adjusted by external resistors and can also be synchronized with an external clock. features ? aec-q100 qualified (note 1) ? up to 2.4mhz movement ? excellent load response by current mode control ? built-in pch/nch output mosfet. ? frequency synchronization with external clock. ? output error monitor terminal (pgood terminal) ? adjustable output voltage and oscillation frequency by external resistors. ? built-in self-reset type overcurrent protection. ? built-in output overvoltage/short circuit detection. ? built-in temperature protection (tsd) and uvlo. (note 1: grade 1) applications ? automotive battery-powered supplies (cluster panels, car multimedia) ? industrial / consumer supplies ? other electronic equipment key specifications ? operating temperature ra nge(ta): -40c to +125c ? input voltage range: 2.6v to 5.5v ? output current: 4.0a(max) ? reference voltage accuracy: 1.5 % ? output voltage range: 0.6v to 5.0v ? switching frequency: 0.3mhz to 2.4mhz package w(typ) x d(typ) x h(max) 4.00mm x 4.00mm x 1.00mm typical application circuit vqfn20sv4040 t vi y t downloaded from: http:///
datasheet d a t a s h e e t 2/36 tsz02201-0j3j0al01140-1-2 ? 2016 rohm co., ltd. all rights reserved. 26.apr.2016 rev.001 www.rohm.co.jp tsz22111 15 001 BD90541MUV-C contents general descr iption ........................................................................................................... ............................................................. 1 features ............................................................................................................................... ........................................................... 1 applicat ions .................................................................................................................. .................................................................. 1 key specific ations ............................................................................................................ .............................................................. 1 package .............................................................................................................................. .................................................... 1 typical applicat ion circu it ................................................................................................... ............................................................ 1 conten ts ...................................................................................................................... ................................................................... 2 pin configur ations ............................................................................................................ .............................................................. 3 pin descrip tions .............................................................................................................. ................................................................ 3 block di agram ................................................................................................................. ............................................................... 4 description of blocks ......................................................................................................... ............................................................. 4 absolute maxi mum rati ngs ...................................................................................................... ...................................................... 6 thermal re sistanc e ............................................................................................................ ............................................................ 6 recommended operat ing condit ions .............................................................................................. ............................................... 7 electrical characteristics ............................................................................................................................... .................................. 8 typical perform ance curv es .................................................................................................... ....................................................... 9 description of operatio n and timi ng char t ..................................................................................... .............................................. 14 selection of co mponents external ly connected .................................................................................. ......................................... 17 recommended parts manufacture r list............................................................................................ ............................................ 23 application ex amples 1......................................................................................................... ........................................................ 24 application ex amples 2......................................................................................................... ........................................................ 26 notes on the pc b layout ....................................................................................................... ...................................................... 28 power dissi pation ............................................................................................................. ............................................................ 30 i/o equivalent circuits ....................................................................................................... ........................................................... 31 operational notes ............................................................................................................. ............................................................ 32 ordering info rmation .......................................................................................................... ........................................................... 34 marking di agrams .............................................................................................................. ........................................................... 34 physical dimension, tape and reel in formation ................................................................................. .......................................... 35 revision hi story .............................................................................................................. .............................................................. 36 downloaded from: http:///
datasheet d a t a s h e e t 3/36 tsz02201-0j3j0al01140-1-2 ? 2016 rohm co., ltd. all rights reserved. 26.apr.2016 rev.001 www.rohm.co.jp tsz22111 15 001 BD90541MUV-C pin configurations pin descriptions e-pad is a back radiation pad. excellent radiation property is obtainable by connection to internal pcb ground-plane using multiple via. use ctl1 terminal by applying 2.1 v or higher when enable is on. use ctl2 terminal by short-circuiting to gnd. if n.c pin is shorted to gnd, heat radiation performance becomes higher. pin no. symbol function pin no. symbol function 1 sw sw pin 11 ss soft start time setting pin 2 sw sw pin 12 fb output feedback pin 3 n.c - 13 n.c - 4 pvin power supply pin for output fet 14 rt operating frequency setting pin 5 pvin power supply pin for output fet 15 sel rt setting frequency/ synchronization select pin 6 vin power supply pin 16 sync external clock input pin 7 en enable pin 17 ctl2 test pin 8 ctl1 test pin 18 pgood power good output pin 9 gnd gnd pin 19 pgnd g nd pin for output fet 10 comp error amp output pin 20 pgnd gnd pin for output fet vqfn20sv4040 pgnd pgnd pgood ctl2 sync vin en gnd comp ctl1 downloaded from: http:///
datasheet d a t a s h e e t 4/36 tsz02201-0j3j0al01140-1-2 ? 2016 rohm co., ltd. all rights reserved. 26.apr.2016 rev.001 www.rohm.co.jp tsz22111 15 001 BD90541MUV-C block diagram description of blocks ? error amplifer this is an error amplifier using reference voltage of 0.6v (typ) and fb terminal volt age as input. (refer to p. 21 to p. 22 for phase compensation setting method). duty width of switching pu lse is controlled with com p of error amplifier output. output voltage is set using fb terminal. phase compensati on can be adjusted by connecting capacitor and resistor to comp terminal. ? soft start this is a function for preventing oversh oot of output voltage by gradually rais ing non-inverting i nput voltage of error amplifier to gradually increase duty of switching pulse at power on. soft start can be set by connecting a capacitor between gnd terminals with ss terminal. (refer to p. 22.) ? oscillator oscillation frequency of 0.3 mhz to 2.4 mhz can be set by connecting a resistor between rt terminal and gnd terminal in the circuit which generates pulse waveform to be input to slope. (refer to figure 18 on p. 21)oscillator output sends clock signal to drv. oscillator output is also used as the clock of scp counter. ? slope this is the block for generating saw-t ooth wave from the clock formed by os cillator. generated saw-tooth wave is combined with feedback current of coil current and sent to pwm comparator. ? pwm comparator this is a comparator that compares slope output and erro r amplifier output. ? drv this is a latch circuit having oscillator output (set) and pwm comparator output (reset) as input. it generates pwm control signal and outputs gate signal for fet drive. downloaded from: http:///
datasheet d a t a s h e e t 5/36 tsz02201-0j3j0al01140-1-2 ? 2016 rohm co., ltd. all rights reserved. 26.apr.2016 rev.001 www.rohm.co.jp tsz22111 15 001 BD90541MUV-C ? tsd (thermal shut down) this is an overheat protection circuit. in order to prevent ic thermal destruction/runaway, output is turned off when chip temperature rises to about 150c or higher. it is recovered w hen temperature returns to constant temperature. however, since overheat protection circuit is ess entially built-in for the purpose of protecti on of ic itself, carr y out thermal design to keep chip temperature below about 150c as tsd detection temperature. ? ocp v th (over current protection) this is an overcurrent protection circuit. when output pch power mos fet is tu rned on and voltage between drain and source exceeds internal reference voltage value, overcurrent protection activates. this overcurrent protection is self-reset type. when overcurrent protection activates, duty becomes small and output voltage is reduced. however, since these protection circuits are effective in protection from destructi on due to sudden accidents, avoi d using them when continuous protection circuit is in action. ? scp (short current protection) this is a load short-circuit protection circuit. when the state of output of 60% or lower is de tected in oscillation cycle 25 6 (s), power mos fet is turned off. if output voltage is recove red to 60% or higher before completion of 256 cycles, power mos fet is not turned off. this load short-circuit protec tion is cancelled after retention of oscillation cycle 2048 (s), and it is restarted with soft start. elongation of off time results in decrease of mean output current. during startup of power source, this function is masked until output reaches set voltage to prevent startup failure. ? uvlo (under voltage lock-out) this is a low voltage wrong operation prevention circuit. it prevents wrong operation of internal circuits during power source voltage startup and when power sour ce voltage is reduced. power source voltage is monitored and when it is reduced to 2.25 v (typ) or lower, output power mos fet is tur ned off. when uvlo is cancelled, it is restarted with soft start. this threshold has hysteresis of 100 mv (typ). ? voltage reference it supplies reference voltage to internal circuits. ? ovp when output voltage is detected to have exceeded set value + 10%, pch fet and nch fet of output is turned off. after detection, when output is reduced and the ov ervoltage state is cancelled, switching ac tion is restarted. there is hysteresis of 2% in overvoltage detection voltage and cancel voltage. ? pgood when output voltage is be low 90% or above 110% of set value, output error state is assumed, and pgood terminal is turned low. there is hysteresis of 2% in detection volt age and cancel voltage. at the time of en off and when uvlo and tsd are in action, pgood terminal out put is also turned low. if vin input voltage exceeds 2 v, pgood output becomes effective. since output is open drain type, connect pull up to vin or an external power source with resistance of 10k ? - 100 k ? . downloaded from: http:///
datasheet d a t a s h e e t 6/36 tsz02201-0j3j0al01140-1-2 ? 2016 rohm co., ltd. all rights reserved. 26.apr.2016 rev.001 www.rohm.co.jp tsz22111 15 001 BD90541MUV-C absolute maximum ratings (ta = 25c) parameter symbol rating unit supply voltage v in , pv in -0.3 to 7 v en pin voltage v en -0.3 to 7 v sync pin voltage v sync -0.3 to v in v sel pin voltage v sel -0.3 to 7 v fb pin voltage v fb -0.3 to v in v comp pin voltage v comp -0.3 to v in v ss pin voltage v ss -0.3 to v in v rt pin voltage v rt -0.3 to v in v pgood pin voltage v pgood -0.3 to 7 v maximum junction temperature tjmax +150 c storage temperature range tstg -55 to +150 c esd rating (hbm) v esd, hbm 2000 v caution: operating the ic over the absolute maximum ratings may damage th e ic. the damage can either be a short circuit between pins or an open circuit between pins and the internal circuitry. therefore, it is import ant to consider circuit protection measures, such as adding a f use, in case the ic is operated over the absolute maximum ratings. thermal resistance (note 1) ? symbol thermal resistance (typ) unit 1s (note 3) 2s2p (note 4) vqfn20sv4040 junction to ambient ja 153.9 37.4 c / w junction to top characterization parameter (note 2) jt 13 7 c / w (note 1) based on jesd51-2a(still-air) (note 2) the thermal characterization parameter to report the difference between junction temperature and the temperature at the top cen ter of the outside surface of the component package. (note 3) using a pcb board based on jesd51-3. layer number of measurement board material board size single fr-4 114.3mm x 76.2mm x 1.57mmt top copper pattern thickness footprints and traces 70 m (note 4) using a pcb board based on jesd51-5,7. layer number of measurement board material board size thermal via (note 5) pitch diameter 4 layers fr-4 114.3mm x 76.2mm x 1.6mmt 1.20mm 0.30mm top 2 internal layers bottom copper pattern thickness copper patte rn thickness copper pattern thickness footprints and traces 70 m 74.2mm x 74.2mm 35 m 74.2mm x 74.2mm 70 m (note 5) this thermal via connects with the copper pattern of all layers. downloaded from: http:///
datasheet d a t a s h e e t 7/36 tsz02201-0j3j0al01140-1-2 ? 2016 rohm co., ltd. all rights reserved. 26.apr.2016 rev.001 www.rohm.co.jp tsz22111 15 001 BD90541MUV-C recommended operating conditions (ta = -40c to +125c) parameter symbol min max unit supply voltage v in , pv in 2.6 5.5 v en pin voltage (note 1,2) v en 0 5.5 v sel pin voltage v sel 0 5.5 v sync pin voltage v sync 0 v in v setting frequency range f rt 0.3 2.4 mhz external clock frequency range f sync 0.3 (note 3) 2.4 (note 3) mhz output voltage range v o 0.6 (note 4) 5.0 v output current i o 0 4 (note 4) a input capacitor c in 1 11 (note 5) - f (note 1) state enters test mode when en terminal exceeds 6 v. (note 2) within action power voltage r ange, the order of startup of power (v in , pv in ), en terminal and sel terminal does not matter. (note 3) as an external signal, input frequency within 25% of frequency set by rt resistance. (note 4) output voltage is limited by sw minimum on time depending on setting of input voltage and oscillation frequency. for the setting range, see setting of output voltage of application part selection method (p. 20). (note 5) ceramic capacitor is recommended. set the capacitance value not to become below minimum value including variation, te mperature property, dc bias property and aging. since malfunction may occur depending on su bstrate patterns and capacitor positions, please design the substrate referring to cautions in substrate layout (p. 28). downloaded from: http:///
datasheet d a t a s h e e t 8/36 tsz02201-0j3j0al01140-1-2 ? 2016 rohm co., ltd. all rights reserved. 26.apr.2016 rev.001 www.rohm.co.jp tsz22111 15 001 BD90541MUV-C electrical characteristics (unless otherwise specified, -40 c ta +125 c v in = pv in = 5 v v en = 3.3 v v ctl1 = 5 v) parameter symbol limit unit conditions min typ max standby circuit current i sdn - 0 1 a v en = 0v, ta = 25c circuit current i in - 700 1050 a v fb = 0.63v, ta = 25c en on voltage v en_on 2.1 - - v en off voltage v en_off - - 0.7 v en input current i en 3 7 14 a v en = 3.3v uvlo on voltage v uvlo_on - 2.25 2.40 v sweep down uvlo off voltage v uvlo_off - 2.35 2.50 v sweep up fb input current i fb - 0 0.5 a v fb = 0.6v reference voltage v ref 0.591 0.600 0.609 v fb = comp comp source current i comp_source -40 -20 -5 a comp sink current i comp_sink 5 20 40 a ss charge current i ss -3 -2 -1 a v ss = 0.6v ss discharge current r ss 100 200 300 ? v ss = 0.6v operating frequency f osc 0.85 1.00 1.15 mhz r6 = 240k ? sw min on time 1 t sw_on1 - 100 - ns i o = 0a sw min on time 2 t sw_on2 - 80 - ns i o = 1a sw min off time t sw_off - 100 - ns sw on-resistance h r on_sw_h - 90 180 m ? i sw = -50ma, v fb = 0.58v sw on-resistance l r on_sw_l - 60 120 m ? i sw = +50ma, v fb = 0.62v over-current detect current i sw_ocp 4.5 7.5 - a sync on voltage v sync_on 0.8 x v in - - v sync off voltage v sync_off - - 0.2 x v in v sync input current i sync 4 10 20 a v sync = 5v pgood sense fb voltage v fb_pgood1 6 10 14 % pull up to vin with 10k ? pgood on-resistance r pgood 60 120 240 ? v pgood = 5v sel on voltage v sel_on 2.1 - - v sel off voltage v sel_off - - 0.7 v sel input current i sel 3 7 14 a v sel = 3.3v downloaded from: http:///
datasheet d a t a s h e e t 9/36 tsz02201-0j3j0al01140-1-2 ? 2016 rohm co., ltd. all rights reserved. 26.apr.2016 rev.001 www.rohm.co.jp tsz22111 15 001 BD90541MUV-C typical performance curves (unless otherwise specified like t he condition of each item of p8) 0.590 0.592 0.594 0.596 0.598 0.600 0.602 0.604 0.606 0.608 0.610 -40-20 0 20406080100120 temperature (c) reference voltage (v) 350 450 550 650 750 850 950 1050 -40-200 20406080100120 temperature (c) circuit current (a) 0.0 0.2 0.4 0.6 0.8 1.0 -40-200 20406080100120 temperature ( ) shutdown circuit current (a) figure 1. standby circuit current vs temperature figure 2. circuit current vs temperature figure 3. reference voltage vs temperature figure 4. reference voltage vs supply voltage 0.590 0.592 0.594 0.596 0.598 0.600 0.602 0.604 0.606 0.608 0.610 2.5 3.0 3.5 4.0 4.5 5.0 5.5 supply voltage : v in (v) reference voltage (v) downloaded from: http:///
datasheet d a t a s h e e t 10/36 tsz02201-0j3j0al01140-1-2 ? 2016 rohm co., ltd. all rights reserved. 26.apr.2016 rev.001 www.rohm.co.jp tsz22111 15 001 BD90541MUV-C typical performance curves - continued 0.85 0.90 0.95 1.00 1.05 1.10 1.15 -40 -20 0 20 40 60 80 100 120 temperature (c) frequency (mhz) 0.7 0.9 1.1 1.3 1.5 1.7 1.9 2.1 -40 -20 0 20 40 60 80 100 120 temperature (c) en on/off voltage (v) 2.10 2.15 2.20 2.25 2.30 2.35 2.40 2.45 2.50 -40 -20 0 20 40 60 80 100 120 temperature (c) uvlo on/off voltage (v) figure 6. uvlo on/off voltage vs temperature uvlo off uvlo on figure 5. en on/off voltage vs temperature r6 = 240k ? figure 8. frequency (1mhz) vs temperature figure 7. frequency vs supply voltage 0.80 0.85 0.90 0.95 1.00 1.05 1.10 1.15 1.20 2.5 3.0 3.5 4.0 4.5 5.0 5.5 supply voltage : v in (v) frequency (mhz) r6 = 240k ? downloaded from: http:///
datasheet d a t a s h e e t 11/36 tsz02201-0j3j0al01140-1-2 ? 2016 rohm co., ltd. all rights reserved. 26.apr.2016 rev.001 www.rohm.co.jp tsz22111 15 001 BD90541MUV-C typical performance curves - continued 255 270 285 300 315 330 345 -40-200 20406080100120 temperature (c) frequency (khz) 2.0 2.2 2.4 2.6 2.8 -40-200 20406080100120 temperature (c) frequency (mhz) -0.5 -0.4 -0.3 -0.2 -0.1 0.0 0.1 0.2 0.3 0.4 0.5 -40-200 20406080100120 temperature (c) fb input current (a) r6 = 75k ? figure 9. frequency (300khz) vs temperature r6 = 910k ? figure 10. frequency (2.4mhz) vs temperature figure 11. fb input current vs temperature 1.0 1.2 1.4 1.6 1.8 2.0 2.2 2.4 2.6 2.8 3.0 -40-200 20406080100120 temperature (c) ss charge current (a) figure 12. ss charge current vs temperature downloaded from: http:///
datasheet d a t a s h e e t 12/36 tsz02201-0j3j0al01140-1-2 ? 2016 rohm co., ltd. all rights reserved. 26.apr.2016 rev.001 www.rohm.co.jp tsz22111 15 001 BD90541MUV-C typical performance curves - continued 5 6 7 8 9 -40 -20 0 20 40 60 80 100 120 temperature (c) over-current detect current (a) 20 40 60 80 100 120 140 -40 -20 0 20 40 60 80 100 120 temperature (c) sw on-resistance (m ? ) 2.0 2.2 2.4 2.6 2.8 3.0 -40-200 20406080100120 temperature (c) sync on/off voltage (v) pch fet nch fet figure 13. sw on-resistance vs temperature figure 14. over-current detect current vs temperature figure 15. sync on/off voltage vs temperature -14 -12 -10 -8 -6 -4 -2 0 2 4 6 8 10 12 14 -40 -20 0 20 40 60 80 100 120 temperature (c) pgood detect voltage (%) pgood falling pgood rising pgood rising pgood falling figure 16. pgood detect voltage vs temperature downloaded from: http:///
datasheet d a t a s h e e t 13/36 tsz02201-0j3j0al01140-1-2 ? 2016 rohm co., ltd. all rights reserved. 26.apr.2016 rev.001 www.rohm.co.jp tsz22111 15 001 BD90541MUV-C typical performance curves - continued 60 80 100 120 140 160 180 -40-20 0 20406080100120 temperature (c) pgood on-resistance ( ? ) figure 17. pgood on-resistance vs temperature downloaded from: http:///
datasheet d a t a s h e e t 14/36 tsz02201-0j3j0al01140-1-2 ? 2016 rohm co., ltd. all rights reserved. 26.apr.2016 rev.001 www.rohm.co.jp tsz22111 15 001 BD90541MUV-C description of operation and timing chart enable control ic operation is controlled by voltage applied on en terminal. when voltage of 2.1 v or higher is applied on en terminal, output starts in 60 s(typ) with soft start. set the startup time on in put voltages, vin and pvin, earlier than soft start time. the circuits can be shut down by opening en terminal or reducing its voltage to below 0.7 v. protection functions since protection circuits are effective in protection from destruction due to sudden accide nts, avoid using protection operation continuously. (1) short current protection (scp) when the state of output of 60% or lower is detected in oscillation cycle 256 (s), power mos-fet is turned off. if output voltage has recovered to 60% or higher before comp letion of 256 cycles, power mos-fet is not turned off. this load short-circuit protection is cancelled after retention for oscillation cycle 2048 (s), and it is restarted with soft start. elongation of off time results in dec rease of mean output current. during startup of power source, this function is masked until output reaches set vo ltage to prevent startup failure. v in , pv in v en v ss v o v pgood 60 s 0.6v setting voltage0.92 soft start setting time downloaded from: http:///
datasheet d a t a s h e e t 15/36 tsz02201-0j3j0al01140-1-2 ? 2016 rohm co., ltd. all rights reserved. 26.apr.2016 rev.001 www.rohm.co.jp tsz22111 15 001 BD90541MUV-C (2) under voltage lock-out (uvlo) it prevents wrong operation of internal circuits during power source voltage startup and when power source voltage is reduced. power source voltage is monitored and when it is reduced to 2.25 v (typ) or lower, output power mos fet is turned off. when uvlo is cancelled, it is restarted with soft start. this threshold has hysteresis of 100 mv (typ). (3) thermal shut down (tsd) in order to prevent ic thermal destruction/runaway, output is turned off when chip temperature rises to about 150c or higher. it is recovered when temperature returns to constant temperature. however, since overheat protection circuit is essentially built-in for the purpose of pr otection of ic itself, carry out thermal design to keep chip temperature below about 150c as tsd detection temperature. (4) over current protection (ocp) when output pch power mos fet is turned on and voltage be tween drain and source exceeds internal reference voltage value, overcurrent protection activates. this ov ercurrent protection is self-reset type. when overcurrent protection activates, duty becomes small and output voltage is reduced. however, since these protection circuits are effective in protection from destruction due to sudden accidents, avoid using them when continuous protection circuit is in action. (5) over voltage protection (ovp) when output voltage is detected to have exceeded set value + 10%, pch fet and nch fet of output is turned off. after detection, when output is reduced and t he overvoltage state is cancelled, swit ching action is restarted. there is hysteresis of 2% in overvoltage detection voltage and cancel voltage. downloaded from: http:///
datasheet d a t a s h e e t 16/36 tsz02201-0j3j0al01140-1-2 ? 2016 rohm co., ltd. all rights reserved. 26.apr.2016 rev.001 www.rohm.co.jp tsz22111 15 001 BD90541MUV-C synchronization to external clock for external synchronization operation, connect frequency setting resistor to r t terminal, apply voltage of 2.1 v or higher on sel terminal, and input synchronous pulse signal to sync terminal. there is no restriction in the order of input in sync terminal and sel terminal. when voltage is applied to both terminals, it star ts external synchronization action. in case no external signal is connected to sync terminal when voltage of 2.1 v or higher is applied to sel terminal (no input is assumed in the case of being fixed at low or high), external synchronization action does not occur. when voltage on sel terminal is reduced to 0.7 v or lower, external synchronization operation ends. in this case, operation is carried out with frequency of internal clk from the cycle next to internal clk. in order to finish external synchronization operation, turn off external signal of sync terminal after sel terminal input voltage becomes low. note that output voltage varies during synchronization to exte rnal signal and switching to internal clk frequency. when using external synchronization, setting range of oscill ation frequency is restricted by external resistance of rt terminal. the setting range becomes within 25% of rt setting frequency. example) when r6 = 240 k ? , since set oscillation frequency is 1.0 mhz, allowable range of external synchronization operation frequency is 0.75 mhz to 1.25 mhz. set low voltage of synchronous pulse signal to 0.2 v v in or lower, and high voltage to 0.8 v v in or higher. set slew rate of rise (fall) at 30 v / s or more, and duty within the range of 20% to 80%. after 4 detections of rise of synchronous pulse , synchronization starts from the fifth rise. timing chart of synchronization to external clock sync sel sw t a ia a t a ia internal clk downloaded from: http:///
datasheet d a t a s h e e t 17/36 tsz02201-0j3j0al01140-1-2 ? 2016 rohm co., ltd. all rights reserved. 26.apr.2016 rev.001 www.rohm.co.jp tsz22111 15 001 BD90541MUV-C selection of components externally connected necessary parameters in designing the power supply are as follows: parameter symbol specification case input voltage v in 5 v output voltage v o 1.2 v output ripple voltage ? v pp 10 mv p-p input range i o typ 1.5 a / max 4.0 a switching frequency f sw 2.0 mhz operating temperature range ta -40 c to +105 c application sample circuit (1) selection of inductor the switching regulator needs an lc filter for smoothing of output voltage in order to supply continuous current to load. when an inductor with large inductance value is selected, ? i l flowing in the inductor becomes small and output ripple voltage is reduced. furthermore, there is a tr ade-off between size and cost of inductance. the inductance value of the inductor is shown in the following equation: ? [h] where: is the maximum input voltage ? is the ripple current of inductor t vi y t downloaded from: http:///
datasheet d a t a s h e e t 18/36 tsz02201-0j3j0al01140-1-2 ? 2016 rohm co., ltd. all rights reserved. 26.apr.2016 rev.001 www.rohm.co.jp tsz22111 15 001 BD90541MUV-C a i o i l t i swlimit (min) i l peak set ? i l to about 30% of maximum output current. when ? i l becomes small, core loss (iron loss) of i nductor, loss of output capacitor due to esr and ? v pp become small. ? ? ? [v] ????? (a) where: is the equivalent series resistance of output capacitor is the output capacitor since ceramic capacitors generally have ultra-low esr, target ? v pp can be satisfied even if ? i l is large to some extent. the advantage is that inductance value of inductor can be set small. small in ductance value contributes to space-saving of sets, because large rated current enables selection of sm all size inductors. the disadvantages are increase of core loss of inductor and reduction of maximum output current. when using other capacitors (elect rolytic capacitor, tantalum capacitor, electro-conductive polymer, etc.) as the output capacitor c o , confirm esr with data sheet of the manufacturer, and determine ? i l to fit ? v pp within allowable range. especially, since capacitance reduction of electrolyt ic capacitor is significant at low temperature, ? v pp increases. pay attention when using it at low temperature the maximum output electric current is lim ited to the overcurrent protection work ing current as shown in the following equation. _ ? [a] where: is the maximum output current _ is the ocp operation current (min) in the case of continuous operation with duty 50%, current control mode may generate sub-harmonic oscillation. this ic has a built-in slope compensation circuit for the purpose of prevention of sub-harmonic oscillation. since sub-harmonic oscillation depends on in crease rate of output switch current i l , sub-harmonic oscillation may be generated when inductance value is reduced to increase slope of i l . on the other hand, when inductance val ue is increased to reduce slope of i l , sufficient stability may not be secured. for stable operation, restrict induc tance value within the range where the following formula is applicable [h] .69 .9 where: is the switching pulse on duty. is the coefficient of current sense(2.53 a / a) is the slope of slope compensation current shield type (closed magnetic path type) inductors are recommended. there is no problem with open magnetic path type if the application is cost-emphasized and free of annoying noise. in this case, consider layout with enough allowance between parts, since there may be influe nce of magnetic field radiation on adjac ent parts. pay special attention to magnetic saturation for ferrite-core type inductors. core sa turation should be avoided under all use conditions. attention is needed since rated current specificat ion is different depending on manufacturers. confirm rated current at maximum ambient temperature of applic ation with the manufacturer. downloaded from: http:///
datasheet d a t a s h e e t 19/36 tsz02201-0j3j0al01140-1-2 ? 2016 rohm co., ltd. all rights reserved. 26.apr.2016 rev.001 www.rohm.co.jp tsz22111 15 001 BD90541MUV-C (2) selection of output capacitor c o select output capacitor based on required esr from formula (a). ? v pp can be minimized by using capacitors with small esr. ceramic capacitor is the best option for satisfying t he requirement. in addition to exhibiting low esr, ceramic capacitors contribute to space saving of sets because of being small. confirm frequency characteristics of esr with manufacturers data sheets, and select a capacito r with low esr at switching frequency used. use ceramic capacitors carefully because dc bias property is remarkable. it is usually desir able that rated voltage of a ceramic capacitor is more than twice as high as maximum ou tput voltage. infl uence of dc bias property can be reduced by selecting a capacitor with high ra ted voltage. furthermore, in order to k eep good temperature characteristics, capacitors with property higher t han that of x7r are recommended. tantalum capacitors and electro-conductive polymer hybr id aluminum electrolytic capacitors have very good temperature characteristics, for which electrolytic capacitors are disadvantageo us. further, since their esr is smaller than that of electrolytic capacitors, relatively small ripple voltage can be obtained in wide temperature range. similar to electrolytic capacitors, they are almost free from dc bias ch aracteristics, and make designing easier. usually, ones with rated voltage about twice as high as ou tput voltage are selected for tantalum capacitors and ones with rated voltage about 1.2 times as high as output voltag e are selected for electro-conductive polymer hybrid aluminum electrolytic capacitors. the disadvantage of tantalum capacitors is that fa ilure mode is short-circuiting and withstand voltage is low. generally, they are not selected for applications such as car-m ounted applications in which reliability is required. since failure mode is open for electro-conductive polymer hybrid alum inum electrolytic capacitors, they are effective to meet the reliability requirement, but they have a disadvantage of generally being expensive. pch step-down switching regulator lowers input voltage v in , and when difference between input and output voltages becomes small, switching pulse begins to disappear before 100% on-duty is reached. as a result, when switching pulse disappears, output ripple voltage may increase. when improvement of output ripple voltage is necessary, followi ng measures should be considered for output capacitor c o . ? use of capacitors with low esr such as ceramic capacito rs, electro-conductive polymer hybrid aluminum electrolytic capacitors, etc. ? increase of capacitance value rated ripple current is specified for these capacitors. pay attention to prevent rms value i co(rms) of output ripple current, obtained by the following formula, from exceeding rated ripple current. the rms values of the ripple current t hat can be obtained in the following equat ion must not exceed the rated ripple current. ? [a] where: is the value of the ripple electric current in addition, total value of capacitance with output line c o(max) , respect to c o , choose capacitance value less than the value obtained by the following equation. _ [f] where: _ is the ocp operation switch current (min) is the soft start time (min) is the maximum output current during startup when the conditions shown abov e are not followed, startup failure, etc. ma y occur. especially when capacitance value is extremely large, overcurrent protection may operate due to inrush current at the time of startup and output may fail to start. confirm the capacitance value well with the set. trans ient responsiveness and stable operation of loop depend on c o . select it after confirming setting of phase compensation circuit. when input voltage variation and load variation are big, decide capacitance value after confirming it wi th actual application corres ponding to specifications. downloaded from: http:///
datasheet d a t a s h e e t 20/36 tsz02201-0j3j0al01140-1-2 ? 2016 rohm co., ltd. all rights reserved. 26.apr.2016 rev.001 www.rohm.co.jp tsz22111 15 001 BD90541MUV-C (3) selection of input capacitor ceramic capacitor is necessary for input capacitor. ceramic capacitor is effective when pl aced as close as possible to pvin terminal. one with capacitance value of 11 f or higher and with rated voltage of 1.2 or more times as high as maximum input voltage and twice or more as high as no rmal input voltage is recommended. set the capacitance value not to be lower than minimum values including variation, temperature characteristics, dc bi as property and aging. since malfunction may occur depending on substrate patterns and capacit or positions, refer to prec autions on substrate layout (p. 28) for designing. in that case, please consider not to exceed the rated ripple curr ent of the capacitor. the ripple current i rms can be calculated using the following equation. ? [a] where: is the rms value of the input ripple electric current as for capacitance values, high capacitance is required w hen input-side impedance is high, such as when wiring from power source to pvin terminal is long. it is necessary to ve rify under actual use conditions that there is no operation problem such as output off state and over shoot of output due to reduction of v in during transient response (4) setting the output voltage the output voltage is determined by the equation below. .6 [v] set feedback resistance r2 at 30k ? or lower in order to minimize error due to bias current. set current flowing in feedback resistance sufficiently small against output current i o , since power efficiency is reduced when r1 + r2 is small. whereas output voltage can be set to 0.6 v or higher, it is limited by sw minimum on time depending on setting of input voltage and oscillation frequency. t he minimum settable output voltage, v outmin , is determined by the following expressions. ___ ___ __ ___ [v] where: __ is the on-resistance h min (60m ? ) __ is the on-resistance l min (45m ? ) is the typ.frequency (setting rt value) __ is sw min on time (90ns with load,110ns without load) the values shown above are values at 25c. though sw minimu m on time tends to increase when temperature rises, variation due to temperature change is cancelled becaus e sw on resistance tends to increase and oscillation frequency tends to decrease at the same time. note that the calculation formula shown above is theoretical. actual properties may vary depending on substrate layout, properties of external parts, etc. (5) selection of schottky diode the schottky diode is optional. depending on the application, efficiency may be improved by addition of schottky diode between sw terminal and pgnd terminal to create current rout e for the time synchronous switch (nch fet) is off. select schottky diode with reverse breakdown voltage higher than input voltage and with rated current higher than maximum inductor current (sum of maximum output current and inductor ripple current). r3 v out fb gnd 0.6v i fb r2 downloaded from: http:///
datasheet d a t a s h e e t 21/36 tsz02201-0j3j0al01140-1-2 ? 2016 rohm co., ltd. all rights reserved. 26.apr.2016 rev.001 www.rohm.co.jp tsz22111 15 001 BD90541MUV-C r6 vs f sw figure 18. r6 vs f sw (6) setting the oscillating frequency internal oscillation frequency is set based on the value of resistance connected between rt terminal and gnd. the setting range is between 0.3mhz and 2.4mhz. relation between resistance value and oscillation frequency is determined as shown in the drawing below. note that operation is not assured w hen the setting is out of the range, which may cause switching to stop. (7) setting the phase compensation circuit high response function is realized by setting zero cross frequency f c of total gain (frequency of gain 0 db) high. however, please note that it is a trade-off with stability. furthermore, since switching regulator application is sampl ed by switching frequency, and gain in switching frequency needs to be suppressed, zero cross frequency needs to be se t to 1/10 or lower of switching frequency. characteristics aimed at by application are as follows. phase-lag when gain is 1 (0 db) is within 135 (phase margin is 45 or more). zero cross frequency is 1/10 or lower of switching frequency. in order to improve responsiveness, switching frequency needs to be increased. phase compensation is set with capacitor and resistance c onnected to comp terminal. system stability is obtained by inserting phase lead fz1 against influence of two phase-lags fp1 and f p2 to cancel them. fp1, fp2 and fz1 are determined as shown in the following formula. [hz] [hz] [hz] frequency characteristics can be optimized by setting appropriate frequencies for the pole and zero. the typical setting is as below. . Q Q [hz] furthermore, phase lead fz2 can be added by inserting of c4 capacitor. [hz] where: is the resistance assumed actual load[ ? ] = output voltage[v] / output current[a] is the error amp transconductance (310 a / v) is the error amp voltage gain (60 db) r6 [k ? ] f [khz] 910 310 680 400 510 520 430 600 300 830 240 1000 160 1400 130 1650 110 1880 100 2000 91 2150 82 2300 75 2450 downloaded from: http:///
datasheet d a t a s h e e t 22/36 tsz02201-0j3j0al01140-1-2 ? 2016 rohm co., ltd. all rights reserved. 26.apr.2016 rev.001 www.rohm.co.jp tsz22111 15 001 BD90541MUV-C [s] setting phase compensation circuit actually, characteristics will vary depending on pcb layou t, arrangement of wiring, kinds of parts used and use conditions (temperature, etc.). be sure to check st ability and responsiveness with actual apparatus. gain phase analyzer or fra is used to check frequency characteristics wi th actual apparatus. contac t the measurement apparatus manufacturer for measurement method, etc. when these measurem ent apparatuses are not available, there is a method of assuming margin by load response. variation of output when the apparatus sh ifts from no load state to maximum load is monitored, and it can be said that responsi veness is low if variation amount is large, and phase margin is small if ringing occurs frequently (twice or more as a guide) after variation. however, confirmation of quantitative phase margin is not possible. measurement of load response (8) setting the soft start time soft start is necessary for prevention of overshoot of output voltage at startup. soft st art time varies depending on capacitance value of capacitor connect ed between ss terminal and gnd terminal. set the startup time on input voltages, vin and pvin, earlier than soft start time. capacitance value of 2200pf to 0.047 f is recommended. . || (9) setting the input filter (r in , c in 2) since v in is used as power source voltage for internal control circ uit, input filter for vin terminal is necessary in order to prevent malfunction due to transient v in variation. connect r in of 10 ? and c in 2 of 1 f. it is necessary to verify under actual use conditions that there is no operation problem such as output off state and overshoot of output due to reduction of v in during transient response. a a inadequate phase margin adequate phase margin. t a i o a v o 0 downloaded from: http:///
datasheet d a t a s h e e t 23/36 tsz02201-0j3j0al01140-1-2 ? 2016 rohm co., ltd. all rights reserved. 26.apr.2016 rev.001 www.rohm.co.jp tsz22111 15 001 BD90541MUV-C recommended parts manufacturer list shown below is the list of the recommended parts manufacturers for reference. type manufacturer url electrolytic capacitor nichicon www.nichicon.com ceramic capacitor murata www.murata.com coil tdk www.global.tdk.com coil coilcraft www.coilcraft.com coil sumida www.sumida.com diode/resistor rohm www.rohm.com downloaded from: http:///
datasheet d a t a s h e e t 24/36 tsz02201-0j3j0al01140-1-2 ? 2016 rohm co., ltd. all rights reserved. 26.apr.2016 rev.001 www.rohm.co.jp tsz22111 15 001 BD90541MUV-C application examples 1 parameter symbol specification case input voltage v in 5v output voltage / output current v o / i o 1.2v / 2a switching frequency f sw 2.0mhz soft start time t ss 1ms operating temperature ta -40 to +105c no package parameters part name(series) type manufacturer l1 w6.9 x h7.2 x l4.5 mm 3 1 h clf7045-d series inductor tdk co1 3216 22 f, x7r, 6.3v gcm series ceramic capacitor murata co2 3216 22 f, x7r, 6.3v gcm series ceramic capacitor murata cin1 3225 22 f, x7r, 10v gcm series ceramic capacitor murata cin2 1608 1 f, x7r, 16v gcm series ceramic capacitor murata cin3 - - - - - cin4 1608 0.01 f, x7r, 50v gcm series ceramic capacitor murata rin 1608 10 ? , 1%, 1/16w mcr03 series chip resistor rohm r0 - short - - - r1 1608 10k ? , 1%, 1/16w mcr03 series chip resistor rohm r2 1608 30k ? , 1%, 1/16w mcr03 series chip resistor rohm r3 1608 30k ? , 1%, 1/16w mcr03 series chip resistor rohm r4 - - - - - r5 1608 10k ? , 1%, 1/16w mcr03 series chip resistor rohm r6 1608 100k ? , 1%, 1/16w mcr03 series chip resistor rohm c1 1608 2200pf, r, 50v gcm series ceramic capacitor murata c2 - - - - - c3 1608 3300pf, r, 50v gcm series ceramic capacitor murata c4 - - - - - t vi y t downloaded from: http:///
datasheet d a t a s h e e t 25/36 tsz02201-0j3j0al01140-1-2 ? 2016 rohm co., ltd. all rights reserved. 26.apr.2016 rev.001 www.rohm.co.jp tsz22111 15 001 BD90541MUV-C reference data of application example 1 0 10 20 30 40 50 60 70 80 90 100 0.01 0.10 1.00 10.00 efficiency (%) output load (a) figure 20. loop response, i o = 2a figure 21. load response, i o =0a ? 2a v o (100mv/div) i o (1a/div) figure 22. load response, i o =1a ? 2a v o (100mv/div) i o (1a/div) figure 19. efficiency vs output load output load (a) efficiency (%) downloaded from: http:///
datasheet d a t a s h e e t 26/36 tsz02201-0j3j0al01140-1-2 ? 2016 rohm co., ltd. all rights reserved. 26.apr.2016 rev.001 www.rohm.co.jp tsz22111 15 001 BD90541MUV-C application examples 2 parameter symbol specification case input voltage v in 5v output voltage / output current v o / i o 3.3v / 2a switching frequency f sw 2.0mhz soft start time t ss 1ms operating temperature ta -40 to +105c (note) please set to 45k ? to combine 30 k ? and 15 k ? about r3. no package parameters part name(series) type manufacturer l1 w6.9 x h7.2 x l4.5 mm 3 1 h clf7045-d series inductor tdk co1 3216 22 f, x7r, 6.3v gcm series ceramic capacitor murata co2 3216 22 f, x7r, 6.3v gcm series ceramic capacitor murata cin1 3225 22 f, x7r, 10v gcm series ceramic capacitor murata cin2 1608 1 f, x7r, 16v gcm series ceramic capacitor murata cin3 - - - - - cin4 1608 0.01 f, x7r, 50v gcm series ceramic capacitor murata rin 1608 10 ? , 1%, 1/16w mcr03 series chip resistor rohm r0 - short - - - r1 1608 20k ? , 1%, 1/16w mcr03 series chip resistor rohm r2 1608 10k ? , 1%, 1/16w mcr03 series chip resistor rohm r3 (1) 1608 30k ? , 1%, 1/16w mcr03 series chip resistor rohm r3 (2) 1608 15k ? , 1%, 1/16w mcr03 series chip resistor rohm r4 - - - - - r5 1608 10k ? , 1%, 1/16w mcr03 series chip resistor rohm r6 1608 100k ? , 1%, 1/16w mcr03 series chip resistor rohm c1 1608 2200pf, r, 50v gcm series ceramic capacitor murata c2 - - - - - c3 1608 3300pf, r, 50v gcm series ceramic capacitor murata c4 - - - - - t vi y t downloaded from: http:///
datasheet d a t a s h e e t 27/36 tsz02201-0j3j0al01140-1-2 ? 2016 rohm co., ltd. all rights reserved. 26.apr.2016 rev.001 www.rohm.co.jp tsz22111 15 001 BD90541MUV-C reference data of application example 2 0 10 20 30 40 50 60 70 80 90 100 0.01 0.10 1.00 10.00 efficiency (%) output load (a) figure 24. loop response, i o = 2a figure 25. load response, i o =0a ? 2a v o (200mv/div) i o (1a/div) figure 26. load response, i o =1a ? 2a v o (100mv/div) i o (1a/div) figure 23. efficiency vs output load output load (a) efficiency (%) downloaded from: http:///
datasheet d a t a s h e e t 28/36 tsz02201-0j3j0al01140-1-2 ? 2016 rohm co., ltd. all rights reserved. 26.apr.2016 rev.001 www.rohm.co.jp tsz22111 15 001 BD90541MUV-C notes on the pcb layout exposed die pad is needed to be connected to gnd. application circuit (vqfn20sv4040) make bold line part as short as possible in wide pattern. arrange input ceramic capacitors cin1, cin3 and cin4 as close as possible to pvin terminal and pgnd terminal. arrange cin2 as close as possible to vin terminal and gnd terminal. arrange r6 as close as possible to rt terminal. arrange r2 and r3 as close as possible to fb termi nal to shorten wirings from r2 and r3 to fb terminal. arrange r2 and r3 as far as possible from l1. influence of sw noise can be reduced by separating power system (input/output capacitor) gnd from reference system (rt, comp) gnd. connect them in common gnd layers as shown in the layout in the next section. r0 is for measurement of frequency char acteristics of feedback and is optional. insertion of resistance in r0 enables measurement of fr equency characteristics of feedback (phase margin) using fra, etc. under normal condit ions, it is shorted. sw sw n.c pvin pvin sel rt n.c fb ss comp gnd ctl1 en vin sync ctl2 pgood pgnd pgnd l1 r2 c3 vo r5 r6 co1 co2 r in c in 1 r3 r4 c4 r0 vin or en c in 3c in 4 c in 2 downloaded from: http:///
datasheet d a t a s h e e t 29/36 tsz02201-0j3j0al01140-1-2 ? 2016 rohm co., ltd. all rights reserved. 26.apr.2016 rev.001 www.rohm.co.jp tsz22111 15 001 BD90541MUV-C reference layout pattern top layer middle 1 layer middle 2 layer bottom layer r0 l1 v o gnd vin gnd pgood sync en sel c o 1 c in 1 c o 2 r5 r6 c4 r4 r3 r2 c3 c1 c2 r1 c in 2 r in c in 3 c in 4 ic reference pcb layout (top view) downloaded from: http:///
datasheet d a t a s h e e t 30/36 tsz02201-0j3j0al01140-1-2 ? 2016 rohm co., ltd. all rights reserved. 26.apr.2016 rev.001 www.rohm.co.jp tsz22111 15 001 BD90541MUV-C power dissipation in thermal design, operate under following conditions. (temperatures described below are guaranteed temper atures. be sure to consider margin, etc.) 1. ambient temperature ta shall be 125 c or lower. 2. chip junction temperature tj shall be 150 c or lower. chip junction temperature tj can be considered in following 2 ways. when obtained from temperature tt at the center of top surface of package under actual use conditions: when obtained from actual ambient temperature ta: reference value vqfn020sv4040 jc top : 40 c /w bottom : 15 c /w ja 153.9 c / w 1-layer pcb 37.4 c / w 4-layer pcb jt 13 c /w 1-layer pcb 7 c /w 4-layer pcb pcb size 114.3 mm x 76.2 mm x 1.6 mm the heat loss p total of the ic can be obtained by the formula shown below: [w] = [w] ? heat dissipation in control circuit [w] ? heat dissipation in output fet __ __ [ ? ] ? on resistance in output fet ? switching pulse duty [w] ? eat dissipation in switching is the input voltage [v] is the circuit current [a] is the load current [a] is the switching pulse duty __ is the h-side fet on resistance [ ? ] __ is the l-side fet on resistance [ ? ] is the switching rise and fall time [s] (typ:7ns) is the oscillating frequency [hz] downloaded from: http:///
datasheet d a t a s h e e t 31/36 tsz02201-0j3j0al01140-1-2 ? 2016 rohm co., ltd. all rights reserved. 26.apr.2016 rev.001 www.rohm.co.jp tsz22111 15 001 BD90541MUV-C i/o equivalent circuits sw en, sel comp ss fb rt sync pgood pvin sw pgnd vin comp gnd vin rt gnd vin sync gnd pgood gnd downloaded from: http:///
datasheet d a t a s h e e t 32/36 tsz02201-0j3j0al01140-1-2 ? 2016 rohm co., ltd. all rights reserved. 26.apr.2016 rev.001 www.rohm.co.jp tsz22111 15 001 BD90541MUV-C operational notes 1. reverse connection of power supply connecting the power supply in reverse polarity can damage the ic. take precautions against reverse polarity when connecting the power supply, such as mounting an external diode between the power supply and the ics power supply pins. 2. power supply lines design the pcb layout pattern to provide low impedance s upply lines. separate the gro und and supply lines of the digital and analog blocks to prev ent noise in the ground and supp ly lines of the digital bloc k from affecting the analog block. furthermore, connect a capacitor to ground at all power supply pins. cons ider the effect of temperature and aging on the capacitance value when using electrolytic capacitors. 3. ground voltage ensure that no pins are at a voltage below that of t he ground pin at any time, even during transient condition. 4. ground wiring pattern when using both small-signal and large-current ground traces, the two ground traces should be routed separately but connected to a single ground at the refer ence point of the application board to av oid fluctuations in the small-signal ground caused by large currents. also ensure that the ground trac es of external components do not cause variations on the ground voltage. the ground lines must be as s hort and thick as possible to reduce line impedance. 5. thermal consideration should by any chance the maximum junction temperature rating be exceeded the rise in temperature of the chip may result in deterioration of the properti es of the chip. in case of exceeding this absolute maximum rating, increase the board size and copper area to prevent exceedin g the maximum junction temperature rating. 6. recommended operating conditions these conditions represent a range within which the expect ed characteristics of the ic can be approximately obtained. the electrical characteristics are guaranteed under the conditions of each parameter. 7. inrush current when power is first supplied to the ic, it is possible that the internal logic may be unstable and inrush current may flow instantaneously due to the internal powering sequence and delays, especially if the ic has more than one power supply. therefore, give special consideration to power coup ling capacitance, power wiring, width of ground wiring, and routing of connections. 8. testing on application boards when testing the ic on an application board, connecting a capacitor directly to a low-impedance output pin may subject the ic to stress. always discharge capacitors completely after each process or step. the ics power supply should always be turned off completely before connecting or removing it from the test setup during the inspection process. to prevent damage fr om static discharge, ground the ic during as sembly and use similar precautions during transport and storage. 9. inter-pin short and mounting errors ensure that the direction and position are correct when mounting the ic on the pc b. incorrect mounting may result in damaging the ic. avoid nearby pins being shorted to each ot her especially to ground, power supply and output pin. inter-pin shorts could be due to many reasons such as metal particles, water droplets (in very humid environment) and unintentional solder bridge deposited in between pins during assembly to name a few. 10. unused input pins input pins of an ic are often connec ted to the gate of a mos transistor. the gate has extremely high impedance and extremely low capacitance. if left unconnec ted, the electric field from the out side can easily charge it. the small charge acquired in this way is enough to produce a signifi cant effect on the conducti on through the transistor and cause unexpected operation of the ic. so unless otherwise specified, unused in put pins should be connected to the power supply or ground line. downloaded from: http:///
datasheet d a t a s h e e t 33/36 tsz02201-0j3j0al01140-1-2 ? 2016 rohm co., ltd. all rights reserved. 26.apr.2016 rev.001 www.rohm.co.jp tsz22111 15 001 BD90541MUV-C operational notes C continued 11. regarding the input pin of the ic this monolithic ic contains p+ isolat ion and p substrate layers between adj acent elements in order to keep them isolated. p-n junctions are formed at the intersection of the p layers with the n layers of other elements, creating a parasitic diode or transistor. for example (refer to figure below): when gnd > pin a and gnd > pin b, the p-n junction operates as a parasitic diode. when gnd > pin b, the p-n junction o perates as a parasitic transistor. parasitic diodes inevitably occur in t he structure of the ic. the operation of parasitic diodes can result in mutual interference among circuits, operational faults, or physical damage. therefore, conditions that cause these diodes to operate, such as applying a voltage lower than the gnd voltage to an input pin (and thus to the p substrate) should be avoided. figure 27. example of monolithic ic structure 12. ceramic capacitor when using a ceramic capacitor, determine the dielectric constant considering the change of capacitance with temperature and the decrease in nominal capacitance due to dc bias and others. 13. area of safe operation (aso) operate the ic such that t he output voltage, output current, and the maximum junction temperature rating are all within the area of safe operation (aso). 14. thermal shutdown circuit(tsd) this ic has a built-in thermal shutdown circuit that prevents heat damage to t he ic. normal operation should always be within the ics maximum junction temperature rating. if however the rating is exceeded for a continued period, the junction temperature (tj) will rise which will activate the ts d circuit that will turn off a ll output pins. when the tj falls below the tsd threshold, the circuits are automatically restored to normal operation. note that the tsd circuit operates in a situation that exceed s the absolute maximum rati ngs and therefore, under no circumstances, should the tsd circuit be used in a set desi gn or for any purpose other t han protecting the ic from heat damage. 15. over current protection circuit (ocp) this ic incorporates an integrated over current protection circuit that is acti vated when the load is shorted. this protection circuit is effective in preventing damage due to sudden and unexpected incidents. however, the ic should not be used in applications characterized by continuous operation or transit ioning of the protection circuit. downloaded from: http:///
datasheet d a t a s h e e t 34/36 tsz02201-0j3j0al01140-1-2 ? 2016 rohm co., ltd. all rights reserved. 26.apr.2016 rev.001 www.rohm.co.jp tsz22111 15 001 BD90541MUV-C ordering information b d 9 0 5 4 1 m u v - ce 2 product name package vqfn20sv4040 product rank c: automotive rank packaging and forming specification e2: embossed tape and reel marking diagrams marking package part number marking 90541 vqfn20sv4040 BD90541MUV-Ce2 vqfn20sv4040 (top view) 90541 part number marking lot numbe r 1pin mark downloaded from: http:///
datasheet d a t a s h e e t 35/36 tsz02201-0j3j0al01140-1-2 ? 2016 rohm co., ltd. all rights reserved. 26.apr.2016 rev.001 www.rohm.co.jp tsz22111 15 001 BD90541MUV-C physical dimension, tape and reel information package name vqfn20sv4040 downloaded from: http:///
datasheet d a t a s h e e t 36/36 tsz02201-0j3j0al01140-1-2 ? 2016 rohm co., ltd. all rights reserved. 26.apr.2016 rev.001 www.rohm.co.jp tsz22111 15 001 BD90541MUV-C revision history date revision changes 26.apr.2016 001 new release downloaded from: http:///
notice-paa-e rev.003 ? 201 5 rohm co., ltd. all rights reserved. notice precaution on using rohm products 1. if you intend to use our products in devices requiring extreme ly high reliability (such as medical equipment (note 1) , aircraft/spacecraft, nuclear power controllers, etc.) and whose malfunction or failure may cause loss of human life , bodily injury or serious damage to property ( specific applications ), please consult with the rohm sales representative in advance. unless otherwise agreed in writin g by rohm in advance, rohm shall not be in any way responsible or liable for any damages, expenses or losses incurred by you or third parties arising from the use of any rohm s products for specific applications. (note1) medical equipment classification of the specific applic ations japan usa eu china class class class b class class ? class 2. rohm designs and manufactures its products subject to stri ct quality control system. however, semiconductor products can fail or malfunction at a certain rate. please be sure to implement, at your own responsibilities, adeq uate safety measures including but not limited to fail-safe desig n against the physical injury, damage to any property, whic h a failure or malfunction of our products may cause. the followi ng are examples of safety measures: [a] installation of protection circuits or other protective devic es to improve system safety [b] installation of redundant circuits to reduce the impact of single or multiple circuit failure 3. our products are no t designed under any special or extraordinary environments or conditions, as exemplified below . accordingly, rohm shall not be in any way responsible or liable for any damages, expenses or losses arising from the use of any rohms products under any special or extraordinary environments or conditions. if you intend to use our products under any special or extraordinary environments or c onditions (as exemplified below), your independent verification and confirmation of product performance, reliabil ity, etc, prior to use, must be necessary: [a] use of our products in any types of liquid, including water, oils, chemicals, and organi c solvents [b] use of our products outdoors or in places where the products are exposed to direct sunlight or dust [c] use of our products in places where the products are e xposed to sea wind or corrosive gases, including cl 2 , h 2 s, nh 3 , so 2 , and no 2 [d] use of our products in places where the products are exposed t o static electricity or electromagnetic waves [e] use of our products in proximity to heat-producing component s, plastic cords, or other flammable items [f] sealing or coating our products with resin or other coating materials [g] use of our products without cleaning residue of flux (even if you use no-clean type fluxes, cleaning residue of flux is recommended); or washing our products by using water or water-soluble cleaning agents for cleaning residue after soldering [h] use of the products in places subject to dew condensation 4. the products are not subject to radiation-proof design. 5. please verify and confirm characteristics of the final or mou nted products in using the products. 6 . in particular, if a transient load (a large amount of load appl ied in a short period of time, such as pulse. is applied, confirmation of performance characteristics after on-board mou nting is strongly recommended. avoid applying power exceeding normal rated power; exceeding the power rating u nder steady-state loading condition may negatively affec t product performance and reliability. 7. de -rate power dissipation depending on ambient temperature. wh en used in sealed area, confirm that it is the use in the range that does not exceed the maximum junction temperature. 8 . confirm that operation temperature is within the specified range desc ribed in the product specification. 9 . rohm shall not be in any way responsible or liable for failure induced under deviant condition from what is defined in this document. precaution for mounting / circuit board design 1. when a highly active halogenous (chlorine, bromine, etc .) flux is used, the residue of flux may negatively affect prod uct performance and reliability. 2. in principle, the reflow soldering method must be used on a surface-mount products, the flow soldering method mus t be used on a through hole mount products. i f the flow soldering method is preferred on a surface-mount p roducts, please consult with th e rohm representative in advance. for details, please refer to rohm mounting specification downloaded from: http:///
notice-paa-e rev.003 ? 201 5 rohm co., ltd. all rights reserved. precautions regarding application examples and external circuits 1. if change is made to the constant of an external circuit, p lease allow a sufficient margin considering variations o f the characteristics of the products and external components, inc luding transient characteristics, as well as static characteristics. 2. you agree that application notes, reference designs, and a ssociated data and information contain ed in this document are presented only as guidance for products use. therefore, i n case you use such information, you are solely responsible for it and you must exercise your own independ ent verification and judgment in the use of such information contained in this document. rohm shall not be in any way respon sible or liable for any damages, expenses or losses incurred by you or third parties arising from the use of such informat ion. precaution for electrostatic this product is electrostatic sensitive product, which may be damaged due to electrostatic discharge. please take p roper caution in your manufacturing process and storage so t hat voltage exceeding the products maximum rating will not be applied to products. please take special care under dry co ndition (e.g. grounding of human body / equipment / solder iro n, isolation from charged objects, setting of ionizer, friction prevention and temperature / humidity control). precaution for storage / transportation 1. product performance and soldered connections may deteriorate if the products are stored in the places where: [a] the products are exposed to sea winds or corrosive gases, in cluding cl2, h2s, nh3, so2, and no2 [b] the temperature or humidity exceeds those recommended by rohm [c] the products are exposed to direct sunshine or condensation [d] the products are exposed to high electrostatic 2. even under rohm recommended storage condition, solderabil ity of products out of recommended storage time period may be degraded. it is strongly recommended to confirm so lderability before using products of which storage time is exceeding the recommended storage time period. 3. store / transport cartons in the correct direction, which is indi cated on a carton with a symbol. otherwise bent leads may occur due to excessive stress applied when dropping of a carton. 4. use products within the specified time after opening a humi dity barrier bag. baking is required before using products of which storage time is exceeding the recommended storage tim e period. precaution for product label a two-dimensional barcode printed on rohm products label is f or rohm s internal use only. precaution for disposition when disposing products please dispose them properly usi ng an authorized industry waste company. precaution for foreign exchange and foreign trade act since concerned goods might be fallen under listed items of export control prescribed by foreign exchange and foreign trade act, please consult with rohm in case of export. precaution regarding intellectual property rights 1. all information and data including but not limited to appl ication example contained in this document is for reference only. rohm does not warrant that foregoing information or data will not infringe any intellectual property rights or any other rights of any third party regarding such information or data. 2. rohm shall not have any obligations where the claims, a ctions or demands arising from the combination of the products with other articles such as components, circuits, systems or ex ternal equipment (including software). 3. no license, expressly or implied, is granted hereby under any inte llectual property rights or other rights of rohm or any third parties with respect to the products or the information contai ned in this document. provided, however, that rohm will not assert its intellectual property rights or other rights a gainst you or your customers to the extent necessary to manufacture or sell products containing the products, subject to th e terms and conditions herein. other precaution 1. this document may not be reprinted or reproduced, in whole or in p art, without prior written consent of rohm. 2. the products may not be disassembled, converted, modified , reproduced or otherwise changed without prior written consent of rohm. 3. in no event shall you use in any way whatsoever the pr oducts and the related technical information contained in the products or this document for any military purposes, includi ng but not limited to, the development of mass-destruction weapons. 4. the proper names of companies or products described in this document are trademarks or registered trademarks of rohm, its affiliated companies or third parties. downloaded from: http:///
datasheet datasheet notice ? we rev.001 ? 2015 rohm co., ltd. all rights reserved. general precaution 1. before you use our pro ducts, you are requested to care fully read this document and fully understand its contents. rohm shall n ot be in an y way responsible or liabl e for fa ilure, malfunction or acci dent arising from the use of a ny rohms products against warning, caution or note contained in this document. 2. all information contained in this docume nt is current as of the issuing date and subj ec t to change without any prior notice. before purchasing or using rohms products, please confirm the la test information with a rohm sale s representative. 3. the information contained in this doc ument is provi ded on an as is basis and rohm does not warrant that all information contained in this document is accurate an d/or error-free. rohm shall not be in an y way responsible or liable for an y damages, expenses or losses incurred b y you or third parties resulting from inaccur acy or errors of or concerning such information. downloaded from: http:///

▲Up To Search▲

Price & Availability of BD90541MUV-C

	To Download BD90541MUV-C Datasheet File
If you can't view the Datasheet, Please click here to try to view without PDF Reader .