EUP7982 ds7982 ver 1.4 may.2005 1 300ma low-noise ultra low-dropout cmos regulator with fault indicator description the EUP7982 low-noise, low-dropout, linear regulator operates from a 2.5v to 5.5v input and is guaranteed to deliver 300ma. the EUP7982 is stable with small 2.2f ceramic capacitor. its performance suits battery powered applications because of its shutdown mode (60 na typ), low quiescent current (110a typ), and ldo voltage (140mv typ). the low dropout voltage allows for more utilization of a battery?s available energy by operating closer to its end-of-life voltage. an output fault-detection circuit indicates loss of regulation. the EUP7982 is available in msop package with 1.8v, 2.5v, 2.8v, 3v, 3.3v, and adjustable versions. feature z 2.5v to 5.5v input range z 300ma guaranteed output current z 60db psrr at 1khz z 50v rms output voltage noise (10hz to 100khz) z 140mv dropout at 300ma z low 110a no-load supply current z 1a shutdown current z fast start-up time z stable with 2.2f ceramic output capacitors z thermal shutdown and short-circuit protection z fault indicator z rohs compliant and 100% lead (pb)-free applications z wireless handsets z dsp core power z battery powered electronics z portable information appliances block diagram figure1.
EUP7982 ds7982 ver 1.4 may.2005 2 typical application circuit figure2. fixed voltage ldo regulator
EUP7982 ds7982 ver 1.4 may.2005 3 pin configurations part number pin configurations EUP7982 msop-8 pin description pin pin description out 1,4 output voltage of the ldo in 2 input voltage of the ldo gnd 3 common ground set 5 output voltage set. not externally connected for the fixed versions. connect ot resistor-divider for adjustable output voltage. cc 6 compensation capacitor for noise reduction shdn 7 shdn places the entire device in shutdown mode when held low. fault 8 fault output. a high-impedance, open-dra in output. if the circuit is out of regulation, fault goes low. in shutdown, this pin is high impedance. connect to gnd if unused
EUP7982 ds7982 ver 1.4 may.2005 4 ordering information order number package type marking operating temperature range EUP7982mir1 EUP7982mir0 msop-8 ca ?? ?? p7982 -40c to 85c EUP7982-18mir1 EUP7982-18mir0 msop-8 c1 ?? ?? p7982 -40c to 85c EUP7982-25mir1 EUP7982-25mir0 msop-8 c2 ?? ?? p7982 -40c to 85c EUP7982-28mir1 EUP7982-28mir0 msop-8 c6 ?? ?? p7982 -40c to 85c EUP7982-30mir1 EUP7982-30mir0 msop-8 c5 ?? ?? p7982 -40c to 85c EUP7982-33mir1 EUP7982-33mir0 msop-8 c3 ?? ?? p7982 -40c to 85c EUP7982 ?? ?? ?? ?? ?? ?? lead free code 1: lead free 0: lead packing r: tape & reel operating temperature range i: industry standard c: commercial package type m: msop output voltage 18: 1.8v 25: 2.5v 28: 2.8v 30: 3.0v 33: 3.3v blank: adjustable
EUP7982 ds7982 ver 1.4 may.2005 5 absolute maximum ratings ? v in , v out , shdn v , v set , v cc , fault v --------------------------------------------- -0.3v to 6v ? fault sink current --------------------------------------------------------------------------------- 20ma ? storage temperature range ------------------------------------------------------------- -65c to 160c ? junction temperature (tj) ------------------------------------------------------------------------ 150c ? lead temperature (10 sec.) ------------------------------------------------------------------------- 260c electrical characteristics unless otherwise specified, all limits guaranteed for v in = v o +0.5v, =v in, c in =c out =2.2f, c cc =22nf, t j =25c. (boldface limits apply for the operating temperature extremes: -40c and 85c) EUP7982 symbol parameter conditions min typ max. unit v in input voltage 2.5 5.5 v -2 +2 ? v o output voltage tolerance 100a -3 +3 % of v out(nom) v o output adjust range adjust version only 1.25 5.5 v i o maximum output current average dc current rating 300 ma i limit output current limit 600 ma i out =0ma 110 200 supply current i out =300ma 240 a i q shutdown supply current v o =0v, shdn =gnd 0.06 1 a i out =1ma 0.4 i out =200ma 90 200 v do dropout voltage i out =300ma 140 mv line regulation i out = 1ma, (v o +0.5v) 5.5v -0.1 0.05 0.1 %/v ? v o load regulation 100a 100khz 50 v rms v ih ,(vo+0.5v) 0.4 v shdn i shdn input bias current shdn =gnd or in 0.1 100 na i set set input leakage set = 1.3v, adjust version only 0.1 2.5 na fault detection voltage v o 2.5v, i out =200ma 150 280 mv fault v fault output low voltage i sink =2ma 0.13 0.25 v fault i fault off-leakage current fault =3.6v, shdn =0v 0.1 100 na t sd thermal shutdown temperature 160 thermal shutdown hysteresis 20 c t on start-up time c out =10f, v o at 90% of final va l u e 80 s shd n v
EUP7982 ds7982 ver 1.4 may.2005 6 typical operating characteristics unless otherwise specified, v in = v o + 0.5v, c in =c out = 2.2 f, c cc = 22 nf, t j = 25c, v shdn =v in supply current vs. input voltage(sot25) 0 25 50 75 100 125 150 175 2.6 3 3.4 3.8 4.2 4.6 5 5.4 5.8 input voltage(v) supply current(ua) ta= 25 ta= 85 tj=-40 dropout voltage vs. load current 0 20 40 60 80 100 120 140 160 0 50 100 150 200 250 300 load current(ma) dropout voltage(mv) tj= -40 tj=25 tj=85 fault dectect threshold vs load current 0 25 50 75 100 125 150 175 200 0 50 100 150 200 250 300 load current(ma) fault detect threshold(mv) supply current vs load current 0 50 100 150 200 250 300 0 50 100 150 200 250 300 load current(ma) supply current (ua) tj=25 tj=85 tj=-40 output voltage change vs temperature -0.8 -0.6 -0.4 -0.2 0.0 0.2 -5 5 - 40 - 20 0 20 50 1 00 1 20 140 temperature vout change (%)
EUP7982 ds7982 ver 1.4 may.2005 7 output noise (10khz to 100khz) load transient power-up response line transient response shutdown response power-down response
EUP7982 ds7982 ver 1.4 may.2005 8 application information external capacitors like any low-dropout regulator, the EUP7982 requires external capacitors for regulator stability. the EUP7982 is specifically designed for portable applications requiring minimum board space and smallest components. these capacitors must be correctly selected for good performance. input capacitor a minimum input capacitance of 1f is required between the EUP7982 input pin and ground (the amount of the capacitance may be increased without limit).this capacitor must be located a distance of not more than 1cm from the input pin and returned to a clean analog ground. 1f ceramic capacitor are fine for most end use applications. if a tantalum ca pacitor is used at the input, it must be guaranteed by the manufacturer to have a surge current rating sufficient for the application. no-load stability the EUP7982 will remain stable and in regulation with no external load. this is specially important in cmos ram keep-alive applications. output capacitance the EUP7982 is specifically designed to employ ceramic output capacitors as low as 2.2f. ceramic capacitors below 10f offer significant cost and space savings, along with high frequency noise filtering. higher values and other types and of capacitor may be used, but their equivalent series resistance (esr) should be maintained below 0.5 ? . ceramic capacitor of the value required by the EUP7982 are available in the following dielectric types: z5u, y5v, x5r, and x7r. the z5u and y5v types exhibit a 50% or more drop in capacitance value as their temperature increase from 25c, an important consideration. the x5r generally maintain their capacitance value within 20%. the x7r type are desirable for their tighter tolerance of 10% over temperature. noise bypass capacitor connecting a 33nf capacitor between the c bypass pin and ground significantly reduces noi se on the regulator output. this cap is connected directly to a high impedance node in the bandgap reference circuit. any significant loading on this node will cause a change on the regulated output voltage. for this reason, dc leakage current through this pin must be kept as low as possible for best output voltage accuracy. the types of capacitors best suited for the noise bypass capacitor are ceramic and film. unlike many other ldo?s , addition of a noise reduction capacitor does not effect the load transient response of the device. however, it does affect start-up time. the smaller the capacitance value, the quicker the start-up time. power dissipation and junction temperature specified regulator operati on is assured to a junction temperature of 125c; the maximum junction temperature should be restri cted to 125c under normal operating conditions. this rest riction limits the power dissipation the regulator can handle in any given application. to ensure the junction temperature is within acceptable limits, calculate the maximum allowable dissipation, p d(max) , and the actual dissipation, p d , which must be less than or equal to p d(max) the maximum-power-dissipation limit is determined using the following equation: where: t j max is the maximum allowable junction temperature. r ja is the thermal resistance junction-to-ambient for the package t a is the ambient temperature. the regulator dissipation is calculated using: p d =(v i -v o ) i o power dissipation resulting from quiescent current is negligible. excessive power dissipation triggers the thermal protection circuit. ja a j d(max) r t max t p ? =
EUP7982 ds7982 ver 1.4 may.2005 9 adjustable operation the adjustable version of the EUP7982 has an output voltage range of 1.25v to 6v. the output voltage of the EUP7982 adjustable regulator is programmed using an external resistor divider as shown in figure3. the output voltage is calculated using: where: vref=1.23v typ. (the internal reference voltage) utilize the following equation for adjusting the output to a particular voltage: ? ? ? ? ? ? ? ? ? = 1 1.23v v r p o 2 i choose r 2 =100k to optimize accuracy, power supply rejection, noise and power consumption. in order to improve the stability of the adjustable version, it is suggested that a small compensation capacitor c 1 be placed between out and set figure3. adjustable ldo regulator programming fault detection the EUP7982 provides a fault pin that goes low during out of regulation conditions like current limit and thermal shutdown, or when it approaches dropout. the latter monitors the input-to-output voltage differential and compares it against a threshold that is slightly above the dropout voltage. this threshold also tracks the dropout voltage as it varies with load current. refer to fault detect vs. load current curve in the typical characteristics section. the fault pin requires a pull-up resistor since it is an open-drain output. this resistor should be large in value to reduce energy drain. a100k ? pull-up resistor works well for most applications. shutdown the EUP7982 goes into sleep mode when the shdn pin is in a logic low condition. during this condition, the pass transistor, error amplifier, and bandgap are turned off, reducing the supply current to 60na typical. the shdn pin may be directly tied to v in to keep the part on. fast start-up the EUP7982 provides fast start-up time for better system efficiency. the start-up speed is maintained when using the optional noise bypass capacitor. ) r r (1 v v 2 1 ref o + =
EUP7982 ds7982 ver 1.4 may.2005 10 packaging information msop-8 note 1. package body sizes exclude mold flash and gate burrs 2. dimension l is measured in gage plane 3. tolerance 0.10mm unless otherwise specified 4. controlling dimension is millimeter. converte d inch dimensions are not necessarily exact. dimensions in millimeters dimensions in inches symbols min. nom. max. min. nom. max. a 0.81 0.95 1.10 0.032 0.0375 0.043 a1 0.05 0.09 0.15 0.002 0.004 0.006 a2 0.76 0.86 0.97 0.030 0.034 0.038 b 0.28 0.30 0.38 0.011 0.012 0.015 c 0.13 0.15 0.23 0.005 0.006 0.009 d 2.90 3.00 3.10 0.114 0.118 0.122 e 4.70 4.90 5.10 0.185 0.193 0.201 e1 2.90 3.00 3.10 0.114 0.118 0.122 e ------ 0.65 ----- ------ 0.026 ------ l 0.40 0.53 0.66 0.016 0.021 0.026 y ------ ------ 0.10 ------ ------ 0.004 c 0 ------ 6 0 ------ 6
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