specifications of any and all sanyo semiconductor co.,l td. products described or contained herein stipulate the performance, characteristics, and functions of the described products in the independent state, and are not guarantees of the performance, characteristics, and functions of the described products as mounted in the customer ' s products or equipment. to verify symptoms and states that cannot be evaluated in an independent device, the customer should always evaluate and test devices mounted in the customer ' sproductsor equipment. any and all sanyo semiconductor co.,ltd. products described or contained herein are, with regard to "standard application", intended for the use as general el ectronics equipment (home appliances, av equipment, communication device, office equipment, industrial equ ipment etc.). the products mentioned herein shall not be intended for use for any "special application" (medica l equipment whose purpose is to sustain life, aerospace instrument, nuclear control device, burning appliances, t ransportation machine, traffic signal system, safety equipment etc.) that shall require extremely high level of re liability and can directly threaten human lives in case of failure or malfunction of the product or may cause har m to human bodies, nor shall they grant any guarantee thereof. if you should intend to use our products for app lications outside the standard applications of our customer who is considering such use and/or outside the scope of our intended standard applications, please consult with us prior to the intended use. if there is n o consultation or inquiry before the intended use, our customer shall be solely responsible for the use. 92408 ms/o3098ha/92793ts a8-8023 no.3660-1/7 LA5677M overview the LA5677M supports single-input control of the outputs of two converters of arbitrary types, including step up, step down and inverting. since the LA5677M supports low voltage (3.6 to 18v) and high frequency (1 to 500khz) operation, it is ideal for use in power supplies in battery powered portable equipment. functions ? operates at low voltages (3.6 to 18v). ? can be used with high frequency oscillators (1 to 500khz). ? built-in low input malfunction prevention circuit. ? built-in timer-latch short circuit protection circuit specifications maximum ratings at ta = 25 c parameter symbol conditions ratings unit maximum supply voltage v cc max 20 v error amplifier input voltage v i 20 v collector output voltage v o 20 v collector output current i o 21 ma allowable power dissipation pd max 330 mw operating temperature topr -20 to +85 c storage temperature tstg -40 to +125 c monolithic linear ic dual switching regulator control ic orderin g numbe r : en3660c
LA5677M no.3660-2/7 operating conditions at ta = 25 c ratings parameter symbol conditions min typ max unit recommended supply voltage v cc 3.6 18 v error amplifier input voltage v i 1.05 1.45 v collector output voltage v o -0.3 +18 v collector output current i o 20 ma feedback pin current i ft 45 a feedback resistance r nf 100 k ? timing capacitance c t 150 15000 pf timing resistance r t 5.1 100 k ? oscillator frequency f osc 1 500 khz electrical characteristics at ta = 25 c ratings parameter symbol conditions min typ max unit reference voltage block output voltage vref i or = 1ma 2.40 2.50 2.60 v line regulation v line v cc = 3.6 to 18v 2 10 mv load regulation v load i or = 0.1 to 1ma 1 7.5 mv output voltage temperature variation 0.2 % short circuit output current i osc vref = 0v 3 10 30 ma low input malfunction prevention block high level threshold voltage v th i or = 0.1ma 2.70 v low level threshold voltage v tl i or = 0.1ma 2.58 v hysteresis vhys i or = 0.1ma 80 120 mv reset voltage vr i or = 0.1ma 1.5 1.9 v protection circuit block input threshold voltage vtpc 1.02 1.16 1.30 v input standby voltage vstby no pull-up 0.78 v input latch voltage v l no pull-up 0.74 v input source current ibpc 12 18 27 a comparator threshold voltage vtc 1.2 v oscillator block oscillator frequency f osc c t = 330pf, r t = 10k ? 200 khz f osc standard deviation ? f a all values agree 10 % frequency variation 1 (v cc ) ? f v 1 % frequency variation 2 (ta) ? ft 0.4 % idle period adjustment circuit block input bias current ibdt 1 a latch mode source current idt 230 a latch input voltage vdt idt = 40 a 2.3 v vt0 with a duty cycle of 0% 2.05 2.25 v input threshold voltage vt100 f osc = 10khz, with a duty cycle of 100% 1.20 1.45 v error amplifier block input offset voltage v io with v (pins 5, 12) = 1.25v -6 +6 mv input offset current i io with v (pins 5, 12) = 1.25v -100 +100 na input bias current i b with v (pins 5, 12) = 1.25v 160 500 na common mode input voltage range v icr v cc = 3.6 to 18v 1.05 1.45 v open loop gain a v r nf = 200k ? 80 db unity gain bandwidth g b 1.5 mhz common mode rejection ratio cmmr 80 db continued on next page.
LA5677M no.3660-3/7 continued from preceding page. ratings parameter symbol conditions min typ max unit maximum output voltage amplitude (1) v o + m vref-0.1 v maximum output voltage amplitude (2) v o ? m 1.0 v output sink current (pins 5, 12) i o + m v id = -0.1v, v o = 1.25v 1.6 ma output source current (pins 5, 12) i o ? m v id = 0.1v, v o = 1.25v -70 a output block output leakage current i leak v o = 18v 10 a output saturation voltage vsat i o = 10ma 1.0 2 v short circuit output current i os v o = 6v 60 ma pwm comparator block vt0 with a duty cycle of 0% 2.05 2.25 v input threshold voltage vt100 f osc = 10khz, with a duty cycle of 100% 1.20 1.45 v input sink current (pins 5, 12) i in + m with v (pins 5, 12) = 1.25v 1.6 ma input source current (pins 5, 12) i in ? m with v (pins 5, 12) = 1.25v -70 a whole device standby current i cc 1 output off state 1.6 2.2 ma average supply current i cc 2 r t = 10k ? 1.9 2.6 ma package dimensions unit : mm (typ) 3035b sanyo : mfp16(225mil) 1 8 16 9 10.0 0.63 6.4 0.15 0.35 1.27 (0.56) 4.4 (1.5) 1.7max 0.1 -20 0 20 40 60 80 100 0 400 300 200 100 pd max -- ta 330 ambient temperature, ta -- c allowable power dissipation, pd max -- mw 85
LA5677M no.3660-4/7 pin assignment 1 c t 2 3 4 5 6 7 8 16 15 14 13 12 11 10 9 LA5677M r t op1 + op1 - op1 out dead time1 out1 gnd v cc out2 dead time2 op2 out op2 + op2 - s.c.p vref top view pin function pin no. pin name function pin no. pin name function 1 c t triangle wave oscillator capacitor connection 9 v cc power supply input 2 r t triangle wave oscillator resistor connection 10 out2 output 2 3 op1 + error amplifier 1 + input 11 dead time2 dead time 2 control 4 op1 - error amplifier 1 - input 12 op2 out error amplifier 2 output 5 op1 out error amplifier 1 output 13 op2 - error amplifier 1 - input 6 dead time1 dead time 1 control 14 op2 + error amplifier 1 + input 7 out1 output 1 15 s.c.p short ci rcuit protection circuit connection 8 gbd ground connection 16 vref reference voltage (2.5v) block diagram c t r t op1 + op1 - op1 out dead time1 out1 gnd dead time2 op2 out vref 16 3 4 2.5v vref = +2.5v 5 12 op2 + op2 - 14 13 vref 2 2.0v 1.4v 11 6 vref u.v.l.o. latch s rr vref vref vref s.c.p 15 1 2 7 10 out2 8 pwm comparator 2 pwm comparator 1 v cc 9 triangle wave oscillator reference voltage error amplifier 2 error amplifier 1
LA5677M no.3660-5/7 operation overview 1. reference voltage block the reference voltage block uses a 2.5v reference voltage. this voltage is made available to external circuits from pin 16, and at the same time is used as the reference power supply by internal circuits. 2. low input malfunction prevention circuit block the low input malfunction prevention circuit prevents incorrect operation when the power supply is brought up or during brief voltage drops. after power is applied and the reference voltage reaches vbe, the output transistors are held off until the power supply voltage becomes 2.72v (typical). the dead time control pin voltage is held at the high level (vref) and the short circuit protection pin is held low (the initial state). since this circuit has a hysteresis of 120mv (typical) chattering due to power supply ri pple can be prevented to a certain extent. 3. timer-latch short circuit protection circuit during output overload, the timer-latch short circuit protection circuit?s short circuit protection comparator turns off q86 when the error amplifier inputs a low level signal (a vo ltage less than vref/2) to one or both of the short circuit protection comparator?s two non-inverting inputs. at this time the pin 15 voltage increases from about 0.75v (steady state) towards vref as the external capacitor is charged from vref through resistor r41 (80k ? ). when the capacitor is charged to about 1.2v, the protection latch is set, the output transi stors are turned off, and the idle time becomes 100%. this also turns on q97 which resets the protection enable stat e. the latch circuit reset voltage is under 1.9v (typical). v pe 1 = vref {1 ? exp (?t1/r41 c pt )} v pe 2 = vref {1 ? exp (?t2/r41 c pt )} 0.75 = 2.5 {1 ? exp (?t1/80k c pt )} 1.20 = 2.5 {1 ? exp (?t2/80k c pt )} t1 = 28.56k c pt t2 = 52.31k cpt t pt = t2 ? t1 = 23.75k c pt cpt = 42.1 t pt [ f] q86 c pt sr protection latch u.v.l.o. q97 15 vref r41 80k ? 1/2 vref error amplifier output 1 error amplifier output 2 short circuit protection comparator figure 1 timer-latch short circuit protection circuit
LA5677M no.3660-6/7 c t -- r t 1k 10k 100k 1m 2 3 57 2 3 57 2 3 57 1k 10k 100k 1m 2 3 5 7 2 3 5 7 2 3 5 7 v cc = 6v ta = 25 c c = 15000pf c = 1500pf c = 150pf timing resistance, r t -- ? oscillator frequency, c t -- hz figure 2 timing resistance/oscillator frequency characteristics 4. triangle wave oscillator block the triangle wave oscillator generates an essentially symme tric triangle wave using a timing capacitor and resistor attached to the c t pin (pin 1) and the r t pin (pin 2), respectively. the voltage amplitude is between 1.4 and 2.0v with pin 2 stabilized at 1v. the oscillator frequency is determined by the external capacitor and resistor. 5. idle period adjustment circuit block the idle period adjustment circuit consists of pwm comparators 1 and 2, each of which has one non-inverting and two inverting inputs. the output pulse width (on time) is controll ed according to the input voltage. pins 6 and 11 are dead time control pins, and are used to limit the maximum value of the pulse width. a pin voltage of 2.05v (typical) or over results in the output being off for the whole period, and a pin voltage of 1.45v (typical) or lower results in the output being on for the whole period. 6. error amplifier block error amplifiers 1 and 2 are amplifiers for detecting the output voltages, i.e., the LA5677M application system output voltages. since the common mode input voltage range is 1.05 to 1.45v, we recommend setting their input voltages to vref/2. pins 5 and 12 are the output pins, and the gain is set and the frequency characteristic s adjusted with a resistor and a capacitor connected betw een the outputs and the non-inverting inputs of each amplifier. the outputs are also connected to the short circuit protection circuit detection circuit. 7. output block the outputs are single end open collector outputs with an npn darlington pair structure.
LA5677M ps no.3660-7/7 sanyo semiconductor co.,ltd. assumes no responsib ility for equipment failures that result from using products at values that exceed, even momentarily, rate d values (such as maximum ra tings, operating condition ranges, or other parameters) listed in products specif ications of any and all sanyo semiconductor co.,ltd. products described or contained herein. sanyo semiconductor co.,ltd. strives to supply high-qual ity high-reliability products, however, any and all semiconductor products fail or malfunction with some probabi lity. it is possible that these probabilistic failures or malfunction could give rise to acci dents or events that could endanger human lives, trouble that could give rise to smoke or fire, or accidents that could cause dam age to other property. when designing equipment, adopt safety measures so that these kinds of accidents or e vents cannot occur. such measures include but are not limited to protective circuits and error prevention c ircuits for safe design, redundant design, and structural design. upon using the technical information or products descri bed herein, neither warranty nor license shall be granted with regard to intellectual property rights or any other rights of sanyo semiconductor co.,ltd. or any third party. sanyo semiconductor co.,ltd. shall not be liable f or any claim or suits with regard to a third party's intellctual property rights which has resulted from the use of the technical information and products mentioned above. information (including circuit diagr ams and circuit parameters) herein is for example only; it is not guaranteed for volume production. any and all information described or contained herein are subject to change without notice due to product/technology improvement, etc. when designing equi pment, refer to the "delivery specification" for the sanyo semiconductor co.,ltd. product that you intend to use. in the event that any or all sanyo semiconductor c o.,ltd. products described or contained herein are controlled under any of applicable local export control laws and regulations, such products may require the export license from the authorities conc erned in accordance with the above law. no part of this publication may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying and recording, or any in formation storage or retrieval system, or otherwise, without the prior written consent of sanyo semiconductor co.,ltd. application circuit example +5v, 1a step-down converter and -5v, 0.5a polarity inverting converter using a 12v input. 1 2 3 4 5 6 7 8 16 15 14 13 12 11 10 9 LA5677M c6 1500pf r6 10k ? r5 10k ? c7 15000pf r8 47k ? r9 2k ? r4 10k ? c3 0.1 f c8 470pf c9 0.47 f vr3 50k ? r14 470 ? r13 100 ? l2 200 h c12 1000 f r10 10k ? + 2sa1470 2sa1470 r12 270 ? r11 47 ? c5 15000pf r7 47k ? c4 470 f c2 0.47 f r1 1k ? r3 3k ? c11 1000 f + l1 200 h +5v 1a ? 5v 0.5 a c10 1000 f c1 0.47 f vr2 50k ? r1 220k ? vr1 50k ? v cc = 12v + this catalog provides information as of september, 2008. specifications and information herein are subject to change without notice.
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