utc 3563 linear integrated circuit utc unisonic technologies co., ltd. 1 qw-r103-013,b high-efficiency dc/dc converter description the utc 3563 is a monolithic control circuit containing the primary functions required for dc to dc converters and highside-sensed constant current source. the device consists of an internal temperature compensated reference, comparator, controlled duty cycle oscillator with an active current sense circuit, bootstrapped driver, and high current output switch. this device is specifically designed to construct a constant current source for battery chargers with a minimum number of external components. bootstrapped driver can drive the npn output switch to saturation for higher efficiency and less heat dissipation. the utc 3563 can deliver 1.5a continuous current without requiring a heat sink. features *3v to 30v input voltage operation. *internal 2a peak current switch. *1.5a continuous output current. *bootstrapped driver. *high side current sense capability. *high efficiency (up to 90%) *internal 2% reference. *low quiescent current at 1.6ma. *frequency operation from 100hz to 100khz. dip-8 sop-8 applications *constant current source for battery chargers. *saver for cellular phones. *step-down dc-dc converter module. pin configuration dc de cf gnd boost is vcc fb 1 2 3 4 8 7 5 6
utc 3563 linear integrated circuit utc unisonic technologies co., ltd. 2 qw-r103-013,b block diagram pin symbol description pin symbol description 1 dc 2a switch collector 5 fb feedback comparator inverting input 2 de darlington switch emitter 6 vcc power supply input 3 cf oscillator timing capacitor 7 is highside current sense input (v cc -v is =300mv) 4 gnd power ground 8 boost bootstrapped driver collector
utc 3563 linear integrated circuit utc unisonic technologies co., ltd. 3 qw-r103-013,b absolute maximum ratings (ta=25 c) parameter symbol value unit supply voltage vcc 30 v comparator input voltage range vi -0.3~+30 v switch collector voltage v c (switch) 30 v switch emitter voltage v e (switch) 30 v switch collector to emitter voltage v ce (switch) 30 v driver collector voltage v c (driver) 30 v switch current i sw 2 a power dissipation (ta=25 c) dip-8 sop-8 1000 625 mw mw thermal resistance dip-8 sop-8 100 160 c/w c/w operating junction temperature tj 125 c operating ambient temperature range ta -20~+85 c storage temperature range tstg -65~+150 c electrical characteristics (vcc=5.0v, ta=25 c, unless otherwise specified) parameter symbol test conditions min typ. max unit oscillator charging current i chg 5v vcc 30v 10 25 40 a discharging current i dischg 5v vcc 30v 100 150 200 a voltage swing vosc pin 3 0.6 v discharge to charge current ratio i dischg / i chg v is =vcc 6.0 current limit sense voltage vcc -v is i chg =i dischg 250 300 350 mv output switch saturation voltage, emitter follower connection v ce(sat) i de =1.0a, v boost =v dc =vcc 1.5 1.8 v saturation voltage v ce(sat) i dc =1.0a, i boost =50ma, (forced ? 20) 0.4 0.7 v dc current gain h fe i sc =1.0a v ce =5.0v 35 120 collector off state current i c(off) v ce =30v 10 na comparator threshold voltage v fb ta=25 c 0 c ta 70 c 1.225 1.210 1.250 1.275 1.290 v v threshold voltage line regulation reg line 3v vcc 30v 0.1 0.3 mv/v input bias current i ib v in =0v 0.4 1.0 a supply current icc v is =vcc, pin 5>v fb , 5.0v vcc 30v, c t =1nf, pin 2=gnd, remaining pins open 1.6 3.0 ma
utc 3563 linear integrated circuit utc unisonic technologies co., ltd. 4 qw-r103-013,b test circuit typical application circuit efficiency vs output current
utc 3563 linear integrated circuit utc unisonic technologies co., ltd. 5 qw-r103-013,b typical performance characteristics
utc 3563 linear integrated circuit utc unisonic technologies co., ltd. 6 qw-r103-013,b application information design formula table calculation step-down step-up t on /t off v out +v f v in(min) -v sat -v out v out +v f -v in(min) v in(min) -v sat (t on +t off ) max 1/f min 1/f min c t 4x10 -5 t on 4x10 -5 t on i c(switch) 2i out(max) t on + t off 2i out(max) ( ) t off rs 0.3/i c(switch) 0.3/i c(switch) l(min) v in(min) -v sat -v out ( ) t on(max) i c(switch) v in(min) - v sat ( ) t on(max) i c(switch) co i c(switch) (t on +t off ) 8v ripple(p-p) i out t on v ripple(p-p) v sat : saturation voltage of the output switch v f : forward voltage of the ringback rectifier the following power supply characteristics must be chosen: v in : norminal input voltage v out : desired output voltage, v out =1.25(1+rb/ra) i out : desired output current f min : minimum desired switching frequency at selected values for v in and i out v ripple(p-p) : desired peak-to-peak output ripple voltage. in practice, the calculated value will need to be increased due to the capacitor equivalent series resistance and board layout. the ripple voltage should be kept to a low value since it will directly affect the line and load regulation. application examples fig. 1 simplified battery charge circuit for ni-cd/ni-mh battery
utc 3563 linear integrated circuit utc unisonic technologies co., ltd. 7 qw-r103-013,b fig.2 battery charge circuit for fluctuating charging current applications fig. 3 step-down converter line regulation: 40mv (v in =10v~20v, @i o =1a) load regulation: 20mv (v in =15v, @i o =100ma~1a) short circuit current: 1.3a (v in =15v, @r l =0.1 )
utc 3563 linear integrated circuit utc unisonic technologies co., ltd. 8 qw-r103-013,b fig. 4 step-down converter with external 5v bootstrap fig. 5 step-up converter line regulation: 100mv (v in =8v~16v, @io=200ma) load regulation: 40mv (v in =12v, @i o =80ma~200ma)
utc 3563 linear integrated circuit utc unisonic technologies co., ltd. 9 qw-r103-013,b fig. 6 step-up converter with external npn switch fig. 7 inverting converter line regulation: 20mv (v in =4.5v~6v, @i o =100ma) load regulation: 100mv (v in =5v, @i o =10ma~100ma)
utc 3563 linear integrated circuit utc unisonic technologies co., ltd. 10 qw-r103-013,b utc assumes no responsibility for equipment failures that result from using products at values that exceed, even momentarily, rated values (such as maximum ratings, operating condition ranges, or other parameters) listed in products specifications of any and all utc products described or contained herein. utc products are not designed for use in life support appliances, devices or systems where malfunction of these products can be reasonably expected to result in personal injury. reproduction in whole or in part is prohibited without the prior written consent of the copyright owner. the information presented in this document does not form part of any quotation or contract, is believed to be accurate and reliable and may be changed without notice.
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