s s p p 3 3 4 4 0 0 6 6 3 3 a a 1 1 . . 5 5 a a b b u u c c k k / / b b o o o o s s t t / / i i n n v v e e r r t t i i n n g g d d c c - - d d c c r r e e g g u u l l a a t t o o r r february 2011 rev. 2.1.0 exar corporation www.exar.com 48720 kato road, fremont ca 94538, usa tel. +1 510 668-7000 ? fax. +1 510 668-7001 general description the SP34063A is a monolithic switching regulator control circuit containing the primary functions required for dc-dc converters. this device consists of an internal temperature compensated reference, voltage comparator, controlled duty cycle o scillator with active current limit circuit, dr iver and high current output switch. this device was specifically designed to be used in buck, boost, and voltage-inverting applic ations with a minimum number of external components. the SP34063A is available in the 8 pin nsoic package. applications ? battery charger circuit ? nics/switches/hubs ? adsl modems ? negative voltage power supply features ? supply voltage: 3v - 36v ? current limiting ? output switch current to 1.5a ? adjustable output voltage ? operation frequency up to 180khz ? low quiescent current ? precision 2% reference ? available in 8 pin nsoic package typical application diagram fig. 1: SP34063A application diagram
s s p p 3 3 4 4 0 0 6 6 3 3 a a 1 1 . . 5 5 a a b b u u c c k k / / b b o o o o s s t t / / i i n n v v e e r r t t i i n n g g d d c c - - d d c c r r e e g g u u l l a a t t o o r r ? 2011 exar corporation 2/9 rev. 2.1.0 absolute maximum ratings these are stress ratings only and functional operation of the device at these ratings or any other above those indicated in the operation sections of the specifications below is not implied. exposure to absolute maximum rating conditions for extended periods of time may affect reliability. power supply voltage v cc ........................................ 40v comparator input volt age ........................... -0.3v to 40v switch collecto r voltag e .......................................... 40v switch emitter voltage (v pin1 =40v) ........................... 40v switch collector to emitter voltage ........................... 40v driver collecto r voltag e........................................... 40v driver collector current (note 2) .......................... 100ma switch curre nt ...................................................... 1.5a storage temperatur e .............................. -65c to 150c esd rating (hbm - huma n body mode l) .................... 2kv operating ratings input voltage range v in ................................ 3.0v to 36v power dissipation (t a =25c - nsoic) ..................780mw junction temperature range .................... -40c to 150c thermal resistance ja .....................................160c/w electrical specifications specifications with standard type ar e for an operating temperature of t a = 25c only. minimum and maximum limits are guaranteed through test, design, or statistical correlation. typical values represent the most likely parametric norm at t a = 25c, and are provided for reference purp oses only. unless otherwise indicated, v cc = 5.0v, t a = ?40c to 85c. parameter min. typ. max. units conditions oscillator frequency f osc 30 38 45 khz v pin5 = 0v, ct = 1.0nf, t a = 25c charge current i chg 30 38 45 a v cc = 5.0v to 36v, t a = 25c discharge current i dischg 180 240 290 a v cc = 5.0v to 36v, t a = 25c discharge to charge current ration i dischg /i chg 5.2 6.5 7.5 pin 7 to v cc , t a = 25c current limit sense voltage v ipk(sense) 250 300 350 mv i dischg = i chg , t a = 25c output switch (note 1) saturation voltage, darlington connection v ce(sat) 1.0 1.3 v i sw =1a, pin1,8 connected saturation voltage (note 2) 0.45 0.7 v i sw =1a, r pin8 = 82ohms to v cc , forced ?=20 dc current gain 50 75 i sw =1a, v ce = 5v, t a = 25c collector off-state current 0.01 100 a v ce =36v comparator threshold voltage v th 1.225 1.250 1.275 v t a = 25c 1.210 1.250 1.290 v t a = -40c to 85c threshold voltage line regulation r egline 1.4 5 mv v cc = 3.0v to 36v input bias current i ib -20 -400 na v in = 0v total device supply current i cc 4 ma v cc =5.0v to 36v, ct=1nf, pin 7 = v cc vpin5 >v th note 1: low duty cycle pulse techniques are used during the test program to maintain junction temperature as close to ambient temperature as possible. note 2: if the output switch is driven into hard saturation (non-darlington configuration) at low switch currents ( 300ma) and high driver currents ( 30ma), it may take up to 2.0 s for it to come out of saturation. this condition will shorten the
s s p p 3 3 4 4 0 0 6 6 3 3 a a 1 1 . . 5 5 a a b b u u c c k k / / b b o o o o s s t t / / i i n n v v e e r r t t i i n n g g d d c c - - d d c c r r e e g g u u l l a a t t o o r r ? 2011 exar corporation 3/9 rev. 2.1.0 off time at frequenci es above 30khz, and is magnified at high temperatures. this condition does not occur with a darlington configuration, since the output switch cannot saturate. if a no n-darlington configuration is us ed, the following output drive condition is recommended. forced ? of output switch 10 7 ? ? = ma driver i output i c c * the 100 ? resistor in the emitter of the dr iver device requires about 7.0ma be fore the output switch conducts. block diagram fig. 2: SP34063A block diagram pin assignement fig. 3: SP34063A pin assignment
s s p p 3 3 4 4 0 0 6 6 3 3 a a 1 1 . . 5 5 a a b b u u c c k k / / b b o o o o s s t t / / i i n n v v e e r r t t i i n n g g d d c c - - d d c c r r e e g g u u l l a a t t o o r r ? 2011 exar corporation 4/9 rev. 2.1.0 pin description name pin number description switch collector 1 internal switch transistor collector switch emitter 2 internal switch transistor emitter timing capacitor 3 timing capacitor to cont rol the switching frequency gnd 4 ground pin for all internal circuit comparator inverting input 5 inverting input pin for internal comparator v cc 6 voltage supply i pk sense 7 peak current sense input by monitoring th e voltage drop across an external i sense resistor to limit the peak current through the switch driver collector 8 volt age driver collector ordering information part number temperature range package packing quantity note 1 note 2 SP34063Aen-l -40c t a +85c nsoic-8 bulk lead free SP34063Aen-l/tr -40c t a +85c nsoic-8 2.5k/tape & reel lead free
s s p p 3 3 4 4 0 0 6 6 3 3 a a 1 1 . . 5 5 a a b b u u c c k k / / b b o o o o s s t t / / i i n n v v e e r r t t i i n n g g d d c c - - d d c c r r e e g g u u l l a a t t o o r r ? 2011 exar corporation 5/9 rev. 2.1.0 typical performance characteristics fig. 4: output switch on-off time vs. oscillator timing capacitor fig. 5: timing capacitor waveform fig. 6: oscillator frequency vs. timing capacitor fig. 7: standard supply cu rrent vs. supply voltage fig. 8: emitter follower configuration output switch saturation vs. emitter current fig. 9: common emitter configuration output switch saturation vs. collector current
s s p p 3 3 4 4 0 0 6 6 3 3 a a 1 1 . . 5 5 a a b b u u c c k k / / b b o o o o s s t t / / i i n n v v e e r r t t i i n n g g d d c c - - d d c c r r e e g g u u l l a a t t o o r r ? 2011 exar corporation 6/9 rev. 2.1.0 fig. 10: current limit sense voltage vs. temperature application information t ypical b oost c onverter c ircuit this is a typical boost converter configuration. in the steady state, if the resistor divider voltage at pin 5 is greater than the voltag e in the non-inverting input, wh ich is 1.25v determined by the internal reference, the output of the comparator will go low. at the next switching period, the output switch will not conduct and the output voltage will eventually drop below its nominal voltage until the divider voltage at pin 5 is lower than 1.25. then the output of the comparator will go high, the output switch will be allowed to conduct. since v pin5 = v out *r2/(r1+r2) = 1.25(v), the output voltage can be decided by v out = 1.25v*(r1+r2)/r2(v).
s s p p 3 3 4 4 0 0 6 6 3 3 a a 1 1 . . 5 5 a a b b u u c c k k / / b b o o o o s s t t / / i i n n v v e e r r t t i i n n g g d d c c - - d d c c r r e e g g u u l l a a t t o o r r ? 2011 exar corporation 7/9 rev. 2.1.0 t ypical b uck c onverter c ircuit this is a typical buck converter configuration. the working process in the stea dy state is similar to a boost converter, v pin5 = v out *r2/(r1+r2) = 1.25(v). the output voltage can be decided by v out = 1.25v*(r1+r2)/r2(v). t ypical i nverting c onverter c ircuit v in 4.5v-6v 1.25v reference regulator q s r osc c t i pk + - b a 1 2 3 4 5 6 7 8 r sc 0.24 ohm c t 470pf r1 0.953k r2 8.2k v out -12v/100ma d1 1n5819 l1 88uh c2 1000uf c3 100uf l2 1uh v out optional filter c1 100uf SP34063A this is a typical boost converter configuration. the working process in the steady state is similar to a boost converter, the difference in this situation is that the voltage at the non-inverting pin of the comparator is equal to 1.25v +v out , then v pin5 = v out *r2/(r1+r2) = 1.25v, + v out . the output voltage can be decided by v out = -1.25v*(r1+r2)/r1 (v).
s s p p 3 3 4 4 0 0 6 6 3 3 a a 1 1 . . 5 5 a a b b u u c c k k / / b b o o o o s s t t / / i i n n v v e e r r t t i i n n g g d d c c - - d d c c r r e e g g u u l l a a t t o o r r ? 2011 exar corporation 8/9 rev. 2.1.0 package specification 8-p in nsoic unit: mm (inch)
s s p p 3 3 4 4 0 0 6 6 3 3 a a 1 1 . . 5 5 a a b b u u c c k k / / b b o o o o s s t t / / i i n n v v e e r r t t i i n n g g d d c c - - d d c c r r e e g g u u l l a a t t o o r r ? 2011 exar corporation 9/9 rev. 2.1.0 revision history revision date description 2.0.0 01/16/2009 reformat of datasheet 2.0.1 8/24/2010 pg1, changed operation frequency from 110khz to 180khz fig. 6: changed title to: oscillat or frequency vs. timing capacitor pg7, corrected the inverting converter circuit 2.1.0 02/14/2011 corrected power dissipation value to 780mw under operating ratings added c t =fct(t on ) formula on figure 10 graph updated package specification for further assistance email: customersupport@exar.com exar technical documentation: http://www.exar.com/techdoc/default.aspx? e xar c orporation h eadquarters and s ales o ffices 48720 kato road fremont, ca 94538 ? usa tel.: +1 (510) 668-7000 fax: +1 (510) 668-7030 www.exar.com notice exar corporation reserves the right to make changes to the products contained in this pu blication in order to improve design, performance or reliabilit y. exar corporation assumes no responsibility for the use of any circuits described herein, conveys no license under any patent or other right, and make s no representation that the circuits are free of patent infringement. charts and schedules contai ned here in are only for illustration purposes and may vary depending upon a user?s specific application. while the information in this publication has been carefully checked; no responsibility, however, is assumed for inaccuracies. exar corporation does not recommend the use of any of its products in life support applic ations where the failure or malfunction of the product can reasonably be expected to cause fa ilure of the life support system or to significantly affect it s safety or effectiveness. products are not authorized for use in such applications unless exar corporation receives, in writing, assurances to its satisfaction that: (a) the risk of injury or damage has been minimized; (b) the user assumes all such risks; (c) potential liability of exar corporation is adequately protected under the circumstances. reproduction, in part or whole, without the prior written consent of exar corporation is prohibited.
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