View EUP2412-15JIR1_7696174.PDF datasheet online --- IC-ON-LINE

Datasheet File OCR Text:

eup2412 ds2412 v e r1.1 apr. 2009 1 500khz sync hr onous step-up con verter with 600ma ldo description the eup2412 provid es a high efficiency 500khz synchronous step-up converter and a low noise, high psrr, low dropout (ldo) fixed output linear regulator with independent enable pins. eup2412 input voltage range is 2.2v to 5.5v, making it ideal for applications with either a 2-cell nimh/nicd or a single-cell lithium-ion/polymer batteries. the eup2412 500khz fixed frequency synchronous step-up converter uses smaller external components producing a compact solution for a wide range of load currents. integrated n-channel main switch and p-channel synchronous rectifier greatly improve converter efficiency. internal soft-start function reduces inrush current. the eup2412 synchronous step-up convert regulates the output voltage up to 6v. when the synchronous step-up convert is disabled, the internal conduction path from sw to out is fully blocked. this output disconnect feature isolates the output from the input and reduces the shutdown current less than 0.1a. the eup2412 ldo linear regulator has an independent input supply pin and is capable of delivering up to 600ma load current. it offers high output accuracy, extremely low dropout voltage, low quiescent current and fast start-up time. ldo is designed to work with low-esr ceramic capacitors. only a 2.2uf ceramic output capacitor can make the device stable over the entire load range. optionally connecting a capacitor from bypass pin to gnd gets high psrr. the eu p2412 ldo out put voltage is factory pre-set 1.2v, 1.8v, 2.5v, 2.8v or 3.3v. the eup2412 is available in a 10pin 3mm 3mm td fn-10 package. typical application cir cuit features z wide in pu t voltage range: 2.2v to 5.5v z synchronous step-up converter: - 1.6amp peak current limit - 500khz fixed switching frequency - output is disconnected from the input in shutdown - built-in main switch and synchronous rectifier - internal soft-start z linear regulator: - 600ma output current - 300mv dropout voltage at 600ma - 2% initial accuracy - fast line / load transient response - 70db psrr at 1khz - stable with a 2.2uf ceramic output capacitor - output is discharged to gnd in shutdown - fixed output voltage: 1.2v to 3.6v z thermal shutdown z rohs compliant and 100% lead (fb)-free z available in tdfn33-10 package applicat ions z portable m edia players z cellular phones z bluetooth portable radios and accessories z battery-powered equipments figure 1. application circuit 1 v?mw`r?y?b? www.gofotech.com
eup2412 ds2412 ver1.1 apr. 2009 2 typical application circuit (continued) figure 2. application circuit 2 function block diagram figure 3. functional block diagram n~n?t?m?w3^v?mw`r?y?b?g ?pqls? tel: 0755-8398 3377 / 135 9011 2223 http://www.gofotech.com v?mw`r?y?b? www.gofotech.com
eup2412 ds2412 ver1.1 apr. 2009 3 pin configurations package type pin configurations tdfn-10 pin description pin name description 1,9 gnd ground pins. 2 sw step-up converter switching node. sw is the drain of the internal low-side n-channel mosfet and high-side p-channel mosfet. connect the inductor between input supply and sw. 3 out step-up converter output. 4 inldo ldo input voltage. bypass inldo to gnd with a 2.2f or greater capacitor. 5 vldo ldo output voltage. bypass vldo to gnd with a 2.2f or greater capacitor. 6 bypass ldo internal reference bypass pin for ultra low noise and high psrr application. 7 enldo ldo enable pin. connect this pin to ground or less than 0.4v to disable the device. 8 fb step-up converter feedback input (1.25v nominal). connect the external resistor divider tap to fb pin. the output voltage can be adjusted from 1.25v to 5.5v. 10 en step-up converter enable pin. connect this pin to ground or less than 0.4v to disable the device. n~n?t?m?w3^v?mw`r?y?b?g ?pqls? tel: 0755-8398 3377 / 135 9011 2223 http://www.gofotech.com v?mw`r?y?b? www.gofotech.com
eup2412 ds2412 ver1.1 apr. 2009 4 ordering information order number package type marking operating temperature range eup2412-12jir1 tdfn-10 xxxxx p2412 1t -40 c to +85c EUP2412-15JIR1 tdfn-10 xxxxx p2412 1c -40 c to +85c eup2412-18jir1 tdfn-10 xxxxx p2412 1d -40 c to +85c eup2412-25jir1 tdfn-10 xxxxx p2412 1b -40 c to +85c eup2412-28jir1 tdfn-10 xxxxx p2412 1e -40 c to +85c eup2412-33jir1 tdfn-10 xxxxx p2412 1h -40 c to +85c eup2412 ?? ?? ?? ?? lead free code 1: lead free 0: lead packing r: tape & reel operating temperature range i: industry standard package type j: tdfn n~n?t?m?w3^v?mw`r?y?b?g ?pqls? tel: 0755-8398 3377 / 135 9011 2223 http://www.gofotech.com v?mw`r?y?b? www.gofotech.com
eup2412 ds2412 ver1.1 apr. 2009 5 absolute maximum ratings (1) ? out, en, fb to gnd ---------------------------------------------------------------------- -0.3v to 6v ? inldo, enldo to gnd ------------------------------------------------------------------ -0.3v to 6v ? vldo to gnd ------------------------------------------------------------------- -0.3v to (v inldo +0.3v) ? sw current (2) --------------------------------------------------------- -------------------- -1.6a to +1.6a ? junction temperature ------------------------------------------------------------------------- 150 ?? ? storage temperature range ------------------------------------------------------------- -65 ?? to +150 ?? ? lead temperature ----------------------------------------------------------------------------- 260 ?? ? thermal resistance ja (tdfn-10) -------------------------------------------------------- 48 ?? /w ? esd rating human body model ------------------------------------------------------------------- 2kv recommended operating conditions (3) ? v in --------------------------------------------------------------------------------------------- 2.2 to 5.5v ? v en ,v enldo ---------------------------------------------------------------------------------- 0 to 5.5v ? operating temperature range ------------ --------------------------------------------- -40 ?? to +85 ?? note (1): stress beyond those listed under ?absolute maximum ratings? may damage the device. note (2): sw has internal clamp diodes between gnd-sw and sw-out. applications that forward bias these diodes should take care not to exceed the ic's package power dissipation limits. note (3): the device is not guaranteed to function outside the recommended operating conditions. electrical characteristics t a =+25 ?? , v in = v en =2.4v, v inldo =v enldo =4.3v, unless otherwise specified. eup2412 parameter conditions min. typ. max. unit ldo linear regulator input voltage inldo 2.5 5.5 v por threshold 2.1 v por hysteresis 0.4 v quiescent current i load =0ma 120 180 a shutdown current v enldo =0v 0.1 1 a v in =3.3v+1v p-p ,f=1khz,i load =10ma 70 power supply ripple rejection v in =3.3v+1v p-p ,f=10khz,i load =10ma 70 db enldo logic high voltage t a =-40?? to +85?? 1.5 v enldo logic lo voltage t a =-40?? to +85?? 0.4 v enldo input current v in =5v, v en =5v or 0v -1 1 a start-up time c bypass =10nf 120 s i out =10ma -2 +2 % vldo output voltage accuracy i out =10ma, t a =-40?? to +85?? -3 +3 % output line regulation 3.8v eup2412 ds2412 ver1.1 apr. 2009 6 electrical characteristics t a =+25 ?? , v in = v en =2.4v, v inldo =v enldo =4.3v, unless otherwise specified. eup2412 parameter conditions min typ max. unit step-up converter supply voltage v in 2.2 5 v output voltage range v out 2.5 6 v shutdown current v en =v out =0v, v sw =5v 0.05 1 a supply current v fb =1.3v 390 a feedback voltage fb 1.2 1.25 1.3 v feedback input current v fb =1.2v 50 na switching frequency 310 500 690 khz maximum duty cycle 80 85 90 % en input logic lo voltage 0.4 v en input logic hi voltage 1.4 v en pull down resistor 1 m ? low-side on resistance v out =3.3v 450 m ? low-side switch peak current limit 1 1.6 2 a high-side on resistance v out =3.3v 650 m ? over temperature protection thermal shutdown 160 c thermal shutdown hysteresis 30 c note (4): dropout is defined as v in -v out when v out is 100mv below the value of v out for vin=v out +0.5v. n~n?t?m?w3^v?mw`r?y?b?g ?pqls? tel: 0755-8398 3377 / 135 9011 2223 http://www.gofotech.com v?mw`r?y?b? www.gofotech.com
eup2412 ds2412 ver1.1 apr. 2009 7 typical operating characteristics v in = 2.4v, v out = 3.5v, v inldo = 4.3v, c1=c2=10uf, l1=4.7 h, r1 =178k ? , r2 =100k ? , c3=c4=2.2f, c5=10nf (see figure 1). n~n?t?m?w3^v?mw`r?y?b?g ?pqls? tel: 0755-8398 3377 / 135 9011 2223 http://www.gofotech.com v?mw`r?y?b? www.gofotech.com
eup2412 ds2412 ver1.1 apr. 2009 8 2.4 2.6 2.8 3 3.2 3.4 3.6 0 500 1000 1500 load current (ma) output voltage (v) 3.48 3.485 3.49 3.495 3.5 1.8 2.3 2.8 3.3 vin(v) vout(v) iload=0ma iload=400ma 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 1 10 100 1000 load current(ma) efficiency vin=2.4v vin=3.0v typical operating characteristics (continued) v in = 2.4v, v out = 3.5v, v inldo = 4.3v, c1=c2=10uf, l1=4.7 h, r1 =178k ? , r2 =100k ? , c3=c4=2.2f, c5=10nf (see figure 1). step-up converter efficiency vs load current step-up converter line regulation step-up converter continuous mode operation i load =400ma step-up converter load regulation step-up converter continuous mode operation i load =20ma vsw vout iinuctor vsw vout iinuctor n~n?t?m?w3^v?mw`r?y?b?g ?pqls? tel: 0755-8398 3377 / 135 9011 2223 http://www.gofotech.com v?mw`r?y?b? www.gofotech.com
eup2412 ds2412 ver1.1 apr. 2009 9 85 85.5 86 86.5 87 87.5 88 -40 -20 0 20 40 60 80 100 120 tem pera ture ( ?? ) max duty cycle ( %) typical operating characteristics (continued) operating conditions ?g v in = 2.4v, v out = 3.5v, c in =10uf, c out = 10f, l1=4.7 h, r1 =178k ? , r2 =100k ? step-up converter startup r load =16? step-up converter maximum duty cycle vs temperature ven vsw vout n~n?t?m?w3^v?mw`r?y?b?g ?pqls? tel: 0755-8398 3377 / 135 9011 2223 http://www.gofotech.com v?mw`r?y?b? www.gofotech.com
eup2412 ds2412 ver1.1 apr. 2009 10 ldo linear regulator function descriptions the eup2412 ldo is a high output current, low dropout linear regulator with fast transient response and high psrr. it offers high output accuracy, extremely low dropout voltage, low quiescent current and fast start-up time. it is designed to work with low-esr ceramic capacitor, reducing the amount of the pcb area. only a 2.2uf ceramic capacitor can make the device stable over the whole load range. as shown in the function block diagram, the ldo is composed of the bandgap reference voltage, the error amplifier, p-channel mosfet pass transistor, internal resistor divider and some additional protection circuits. the reference voltage, connected to the cathode terminal of the error amplifier, compares with the feedback voltage to regulate the output voltage to make it constant over the whole load range. if the feedback voltage is lower than the reference voltage, the pass transistor gate is pulled low to increase its conductivity. this allows more current to flow to the output and increases the output voltage. if the feedback voltage is higher th an the reference voltage, the pass transistor allows less current to flow to the output. the feedback point is the output of the internal or external resistor divider connected to the vldo pin. supply input power on reset the input voltage supplies current to the output and the operation voltage of the internal circuit. the input voltage is monitored for power on re set (por) to ensure the ldo is disabled when the input voltage is not high enough for normal operation. the por threshold voltage is 2.1v at vin rising typically. enable/shutdown the ldo is disabled when the enldo pin is connected to ground or the voltage less than 0.4v, reducing the quiescent current to less than 1ua. in the shutdown mode the error amplifier, the reference voltage, the driver and the pass transistor are all disabled. make this pin higher than 1.5v to enable the device. enldo can not be floated. soft stop when the ldo is disabled, an internal 40 0 ? resistor is connected between vldo and gnd. this is intended to discharge c out. the internal resistor is not used when the device turns on. current limit the ldo includes a current limit circuit to monitor the gate voltage of the pass transistor to limit the output current. when the output current is higher than the over-current limit, the circuit will clamp the gate voltage of the pass transistor to keep the current flowing to the output. the typical value is 0.9a. step-up converter function descriptions the eup2412 step-up converter uses 500khz fixed-frequency, current-mode regulation architecture to regulate the output voltage. the step-up converter measures the output voltage through an external resistive voltage divider and compares that to th e internal 1.25v reference to generate the error voltage. the current-mode regulator compares the error voltage to the inductor current to regulate the output voltage. when the step-up converter is disabled (en = low), both power switches are off. there is no current path from sw to out. therefore, the output voltage discharges to ground. when the step-up converter is enabled (en = high), a limited start-current charges the output capacitor through the p-channel mosfet until the output voltage rising close to input voltage, then the part operates in force pwm mode to regulate the output voltage to the final value. the eup2412 step-up converter features a soft-start timer to limit the error amplifier output voltage during startup. to prevent. this prevents excessive inrush current causing premature termination of the s ource voltage at startup. the soft-start also limits the inductor current at startup, forcing the input current to rise slowly to regulate the output voltage. n~n?t?m?w3^v?mw`r?y?b?g ?pqls? tel: 0755-8398 3377 / 135 9011 2223 http://www.gofotech.com v?mw`r?y?b? www.gofotech.com
eup2412 ds2412 ver1.1 apr. 2009 11 application information (see figure 1 and 2) ldo input capacitor c3 a 2.2uf capacitor is required between the inldo pin and the gnd pin. place it as close as possible to the device. there are no requirements for the esr on the input capacitor, but the tolerance and temperature coefficient must be considered when selecting the capacitor to ensure the capacitance will be 2.2uf over the whole operating temperature range. ldo output capacitor c4 the eup2412 ldo is designed specifically to work with very small ceramic output capacitors. a 2.2uf to 10uf with 5m ? to 500m ? esr range is suitable in the eup2412 ldo application circuit. the esr of a typical 2.2uf ceramic capacitor is about 20m ? , which easily meets the esr requirement for stability. the eup2412 ldo will remains stable and in regulation with no external load. this is special important in cmos ram keep-alive applications. step-up converter input capacitor c1 an input capacitor is required to supply the ac ripple current to the inductor, while limiting noise at the input source. multi-layer ceramic capacitors are the best choice as they have extremely low es r and are available in small footprints. use an input capacitor value of 4.7 f or greater. this capacitor must be placed physically close to the device. step-up converter output capacitor c2 a single 4.7 f to 10 f ceramic capacitor usually provides sufficient output capacitance for most applications. larger values up to 22 f may be used to obtain extremely low output voltage ripple and improve transient response. the impedance of the ceramic capacitor at the switching frequency is dominated by the capacitance, and so the output voltage ripple is mostly independent of the esr. the output voltage ripple v ripple is calculated as: where v in is the input voltage, i load is the load current, c2 is the capacitance of the output capacitor and f sw is the 500khz switching frequency. capacitor characteristics more consideration should be taken when selecting the capacitor because its capacitan ce can vary with temperature. the capacitor type x7r or x5 r, which operates over a temperature range of -40 ?? to +85 ?? , will only vary within 15%. some large value ceramic capacitors are manufactured with z5u or t5v temperature characteristics. their capacitance can drop by more than 50% as the temperature goes from 25 ?? to 85 ?? . therefore the capacitor type x7r or x5r is recommended in applications where the ambient temperature will change significantly above or below 25 ??. step-up converter inductor l1 the inductor is required to force the output voltage higher while being driven by the lower input voltage. a good rule for determining the inductance is to allow the peak-to-peak ripple current to be approximately 30%-50% of the maximum input current. make sure that the peak inductor current is below the minimum current limit at the duty cycle used (to prevent loss of regulation due to the current limit variations). calculate the required inductance value l using the equations: where i load(max) is the maximum load current, ? i is the peak-to-peak inductor ripple current and b is efficiency. for the eup2412, typically, 4.7 h is recommended for most applications. choose an inductor that does not saturate at the peak switch current as calculated above with additional margin to cover heavy load transients and extreme startup conditions. setting the step-up converter output voltage set the step-up regulator output voltage by selecting the resistive voltage divider ratio. the voltage divider drops the output voltage to the 1.25v feedback voltage. use a 100k ? resistor for r2 of the volt age divider. determine the high-side resistor r1 by the equation: where v out is the output voltage, v fb is the 1.25v feedback voltage and r2=100k ? . () sw out in out load ripple f2cv vvi v ? = ( ) ifv vvv l sw out in out in ? ? = ? = in )max(load out )max(in v iv i )max(in i%)50%30(i ? = ? ? ? ? ? ? ? ? ? ? = 2r v vv 1r fb fb out n~n?t?m?w3^v?mw`r?y?b?g ?pqls? tel: 0755-8398 3377 / 135 9011 2223 http://www.gofotech.com v?mw`r?y?b? www.gofotech.com
eup2412 ds2412 ver1.1 apr. 2009 12 jaa)max(j)max(d )tt(p ?= thermal considerations thermal protection limits power dissipation in eup2412.when the operation junction temperature exceeds 160c, the otp circuit starts the thermal shutdown function and turns off both ldo and step-up regulator. the device turns on again after the junction temperature cools by 30c. for continuous operation, do not exceed absolute maximum operation junction temperature 150c. the maximum power dissipation depends on the thermal resistance of ic package, pcb layout, the rate of surroundings airflow and temp erature difference between junction to ambient. the maximum power dissipation can be calculated by following formula : where t j(max) is the maximum operation junction temperature 150c, t a is the ambient temperature and the ja is the junction to ambient thermal resistance. n~n?t?m?w3^v?mw`r?y?b?g ?pqls? tel: 0755-8398 3377 / 135 9011 2223 http://www.gofotech.com v?mw`r?y?b? www.gofotech.com
eup2412 ds2412 ver1.1 apr. 2009 13 package information tdfn-10 millimeters inches symbols min. max. min. max. a 0.70 0.80 0.028 0.031 a1 0.00 0.05 0.000 0.002 d1 2.50 0.098 d 2.90 3.10 0.114 0.122 e1 1.70 0.067 e 2.90 3.10 0.114 0.122 l 0.30 0.50 0.012 0.020 b 0.18 0.30 0.007 0.012 e 0.50 0.020 d1 2.40 0.094 n~n?t?m?w3^v?mw`r?y?b?g ?pqls? tel: 0755-8398 3377 / 135 9011 2223 http://www.gofotech.com v?mw`r?y?b? www.gofotech.com

▲Up To Search▲

Price & Availability of EUP2412-15JIR1

	To Download EUP2412-15JIR1 Datasheet File
If you can't view the Datasheet, Please click here to try to view without PDF Reader .