lms5213 80ma, cap, low dropout voltage regulator in sc70 general description the lms5213 is a cap, low dropout voltage regulator with very low quiescent current, 220a typical, at 80ma load. it also has very low dropout voltage, typically 20mv at light load and 330mv at 80ma. the lms5213 provides up to 80ma and consumes a typical of 1a in disable mode. the lms5213 is optimized to work with low value, low cost ceramic capacitors. the output typically require only 0.47f of output capacitance for stability. the enable pin can be tied to v in for easy device layout. the lms5213 is designed for portable, battery powered equipment applications with small space requirements. the lms5213 is available in a space saving 5-pin sc70 package. performance is specified for the ?40c to +125c temperature range and is available in 2.8v fixed voltage. for other output voltage options, please contact national semi- conductor. features n space saving sc70 package n available in 2.8v fixed voltage n guaranteed 80ma output n low quiescent current n low dropout voltage n low temperature coefficient n current and thermal limiting n logic-controlled shutdown n stability with low-esr ceramic capacitors n pin-to-pin replacement for mic ? 5213 applications n cellular phones n battery-powered equipment n bar code scanner n laptop/palmtop computer n high-efficiency linear power supplies typical application connection diagram ds200109-19 sc70-5 ds200109-21 top view december 2000 lms5213 80ma, cap, low dropout voltage regulator in sc70 ? 2000 national semiconductor corporation ds200109 www.national.com
simplified schematic pin description pin number pin name pin function 1v en enable input logic, logic high = enabled logic low = shutdown 2 nc not internally connected 3 gnd ground 4v out output voltage 5v in input voltage ordering information package part number package marking transport media nsc drawing 5-pin sc70 lms5213m7-2.8 l0e 1k units tape and reel maa05a lms5213m7x-2.8 l0e 3k units tape and reel ds200109-11 lms5213 www.national.com 2
absolute maximum ratings (note 1) if military/aerospace specified devices are required, please contact the national semiconductor sales office/ distributors for availability and specifications. esd tolerance (note 2) human body model 2000v junction temperature 150c v in ,v out ,v en ?0.3 to 6.5v soldering information infrared or convection (20 sec) 235c wave soldering (10 sec) 260c (lead temp) operating ratings supply voltages v in 2.7v to 6v v en 0v to v in junction temp. range (note 3) ?40c to +125c storage temperature range ?65c to 150c package themal resistance sc70-5 478c/w electrical characteristics unless otherwise specified, all limits guaranteed for t j = 25c, v in =v out + 1v, i l = 1ma, c l = 0.47f, v en 3 2.0v. bold- face limits apply at the temperature extremes. symbol parameter conditions min (note 5) typ (note 4) max (note 5) units v o output voltage accuracy -3 -4 3 4 % d v o / d t output voltage temp. coefficient (note 10) 50 200 ppm/c d v o /v o line regulation v in =v out +1v to 6v 0.008 0.3 0.5 % d v o /v o load regulation i l = 0.1ma to 80ma (note 6) 0.08 0.3 0.5 % v in -v o dropout voltage (note 7) i l = 100a 20 mv i l = 20ma 70 350 i l = 50ma 180 i l = 80ma 330 600 i q quiescent current v en 0.4v (shutdown) 1 10 a i gnd ground pin current i l = 100a, v en 3 2.0v (active) 160 a i l = 20ma, v en 3 2.0v (active) 180 750 i l = 50ma, v en 3 2.0v (active) 200 i l = 80ma, v en 3 2.0v (active) 220 3000 i gnddo ground pin current at dropout, (note 8) v in =v out(nominal) 0.5v 200 300 a i limit current limit v out = 0v 180 250 ma d v o / d p d thermal regulation (note 9) 0.05 %w enable input v il enable input voltage level logic low (off) 0.6 v v ih logic high (on) 2.0 v i il enable input current v il 0.6v 0.01 1 a i ih v ih 3 2.0v 15 50 a note 1: absolute maximum ratings indicate limits beyond which damage to the device may occur. operating ratings indicate conditions for which the device is intended to be functional, but specific performance is not guaranteed. for guaranteed specifications and the test conditions, see the electrical ch aracteristics. note 2: human body model, 1.5k w in series with 100pf. note 3: the maximum power dissipation is a function of t j(max) , q ja , and t a . the maximum allowable power dissipation at any ambient temperature is p d =(t j(max) t a )/ q ja . all numbers apply for packages soldered directly into a pc board. note 4: typical values represent the most likely parametric norm. note 5: all limits are guaranteed by testing or statistical analysis. note 6: regulation is measured at constant junction temperature using low duty cycle pulse testing. changes in output voltage due to heating effects are cove red by the thermal regulation specification. note 7: dropout voltage is defined as the input to output differential at which the output voltage drops 2% below its nominal value measured at 1v differential . note 8: ground pin current is the regulator quiescent current plus pass transistor base current. the total current drawn from the supply is the sum of the load c urrent plus the ground pin current. note 9: thermal regulation is defined as the change in output voltage at a time ato after a change in power dissipation is applied, excluding load or line regula tion effects. specifications are for an 80ma load pulse at v in = 6v for t = 16ms. lms5213 www.national.com 3
electrical characteristics (continued) note 10: output voltage temperature coefficient is defined as the worst-case voltage change divided by the total temperature range. typical characteristics dropout voltage vs. output current ds200109-12 dropout voltage vs. temperature ds200109-1 dropout characteristics ds200109-6 dropout characteristics ds200109-7 lms5213 www.national.com 4
typical characteristics (continued) ground current vs. output current ds200109-3 ground current vs. supply voltage ds200109-4 ground current vs. temperature ds200109-13 short circuit current vs. input voltage ds200109-5 output voltage vs. temperature ds200109-2 load transient ds200109-14 lms5213 www.national.com 5
typical characteristics (continued) load transient ds200109-16 line transient ds200109-17 line transient ds200109-18 ripple voltage vs. frequency ds200109-8 ripple voltage vs. frequency ds200109-9 noise characteristics ds200109-10 lms5213 www.national.com 6
application information the lms5213 is a low dropout, linear regulator designed primarily for battery-powered applications. the lms5213 can be used with low cost ceramic capacitors, typical value of 0.47f. as illustrated in the simplified schematics, the lms5213 consists of a 1.25v reference, error amplifier, p-channel pass transistor and internal feedback voltage diode. the 1.25v reference is connected to the input of the error amp. the error amp compares this reference with the feedback voltage. if the feedback voltage is lower than the reference, the pass transistor gate is pulled lower allowing more current to pass and increasing the output voltage. if the feedback voltage is too high, the pass transistor gate is pulled up allowing less current to pass to the output. the output volt- age is fedback through the resistor divider. additional blocks include short circuit current protection and thermal protec- tion. the lms5213 features an 80ma p-channel mosfet tran- sistor. this provides several advantages over similar designs using pnp pass transistors including longer battery life. the p-channel mosfet requires no base drive, which re- duces quiescent current considerably. pnp based regulators waste considerable amounts of current in dropout when the pass transistor saturates. they also have high base drive currents under large loads. the lms5213 does not suffer from these problems and consumes only the specified qui- escent current under light and heavy loads. external capacitors like any low-dropout regulators, the lms5213 requires ex- ternal capacitors for regulator stability. the lms5213 is spe- cially designed for portable applications requiring minimum board space and the smallest components. a 0.1f capacitor should be placed from v in to gnd if there is more than 10 inches of wire between the input and ac filter or when a battery is used as the input. this capacitor must be located a distance of not more than 1cm from the input pin and returned to a clean analog ground. the lms5213 is designed to work with small ceramic output capacitors. ceramic capacitors ranging between 0.47f to 4.7f are the smallest and least expensive. no-load stability the lms5213 will remain stable and in regulation with no-load (other than the internal voltage divider). this is especially important in cmos ram keep-alive applications. enable input the lms5213 is shut off by pulling the v en pin below 0.6v; all internal circuitry is powered off and the quiescent current is typically 1a. pulling the v en high above 2v re-enables the device and allows operation. if the shut down feature is not used, the v en pin should be tied to v in to keep the regulator output on all the time. thermal behavior the lms5213 regulator has internal thermal shutdown to protect the device from over heating. under all operating conditions, the maximum junction temperature of the lms5213 must be below 125c. maximum power dissipation can be calculated based on the output current and the voltage drop across the part. the maximum power dissipa- tion is p d(max) =(t j(max) -t a )/ q ja q ja is the junction-to-ambient thermal resistance, 478c/w for the lms5213 in the sc70 package. t a is the maximum ambient temperature t j(max) is the maximum junction tem- perature of the die, 125c when operating the lms5213 at room temperature, the maximum power dissipation is 209 mw. the actual power dissipated by the regulator is p d =(v in -v out )i l +v in i gnd the figure below shows the voltage and currents, which are present in the circuit. substituting p d(max) , determined above, for p d and solving for the operating condition that are critical to the application will give the maximum operating conditions for the regulator circuit. to prevent the device from entering thermal shut- down, maximum power dissipation cannot be exceeded. fixed voltage regulator the lms5213 offers a smaller system solution that is ideal for general-purpose voltage regulation in any handheld device. ds200109-22 figure 1. power dissipation diagram ds200109-20 figure 2. single-cell regulator lms5213 www.national.com 7
physical dimensions inches (millimeters) unless otherwise noted life support policy national's products are not authorized for use as critical components in life support devices or systems without the express written approval of the president and general counsel of national semiconductor corporation. as used herein: 1. life support devices or systems are devices or systems which, (a) are intended for surgical implant into the body, or (b) support or sustain life, and whose failure to perform when properly used in accordance with instructions for use provided in the labeling, can be reasonably expected to result in a significant injury to the user. 2. a critical component is any component of a life support device or system whose failure to perform can be reasonably expected to cause the failure of the life support device or system, or to affect its safety or effectiveness. national semiconductor corporation americas tel: 1-800-272-9959 fax: 1-800-737-7018 email: support@nsc.com national semiconductor europe fax: +49 (0) 180-530 85 86 email: europe.support@nsc.com deutsch tel: +49 (0) 69 9508 6208 english tel: +44 (0) 870 24 0 2171 fran?ais tel: +33 (0) 1 41 91 8790 national semiconductor asia pacific customer response group tel: 65-2544466 fax: 65-2504466 email: ap.support@nsc.com national semiconductor japan ltd. tel: 81-3-5639-7560 fax: 81-3-5639-7507 www.national.com 5-pin sc70-5 nsc package number maa05a lms5213 80ma, cap, low dropout voltage regulator in sc70 national does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and national reserves the righ t at any time without notice to change said circuitry and specifications.
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