http://www.belling.com.cn - 1 - total 7 pages bl8580/1 features no external component required pwm dimming control available low noise and emi led sink current of 20ma independent current sink circuit for each led output versatile supply voltage range low standby current high accuracy current match on each channel applications small size color lcd backlights driver mobile phone, portable device keypad backlights driver descriptoin the bl8580/1 is a cmos based white/blue led driver with stand-alone capability. the driver is primarily designed for led backlighting of lcd display powered by li-ion battery with its high efficiency, low standby current and wide range of input supply voltage, the bl8580/1 is suitable for applications such as portable device display and keypad backlighting. in portable application, three or four-channel led solutions are popular. bl8580 has three led channels with a sot-23-6 package. bl8581 has four led channels with a sop-8 package. typical application ordering information bl8580prc sot-23-6 3 channel pb free 3k/reel -25~125 c BL8581PS sop-8 4 channel pb free 2.5k/reel -25~125 c
http://www.belling.com.cn - 2 - total 7 pages bl8580/1 marking information block diagram pin configuration
http://www.belling.com.cn - 3 - total 7 pages bl8580/1 pin description pin name function led1-ledn rgb or wled cathode connection pin en chip enable pin. high level activates the chip. con nect the pin to vcc if not used, do not leave this pin float ing vcc power supply gnd analog ground. in bl8581, for good led current match, it is recommended that the two gnd pins sho uld be tied together by external copper. absolute maximum rating supply voltage range -0.3v~7v voltage of ledn, en pin -0.3v~7v maximum junction temperature -150 storage temperature range -40~150 lead temperature and time -260 , 10s recommended operating condition parameters min nom max unit supply voltage 2.7 6 v output sink current on each channel 25 ma operating free-air temperature range -25 125 electrical characteristics v dd =3.7v, t a =25 c, no load, input: v ih =3.7v, v il =gnd. (unless otherwise noted) reference data symbols parameters conditions min typ max unit v il en pin low logic 0.4 v v ih en pin high logic 1.7 v i il en pin low input current -1 m a i ih en pin high input current 1 m a v ledl ledn dropout voltage 100 mv i led ledn sink current 19 20 21 ma d i ledn ledn sink current deviation +/-3 % i q quiescent current ven=1 250 400 m a i stby standby supply current ven=0 0.5 m a
http://www.belling.com.cn - 4 - total 7 pages bl8580/1 detailed description bl8580/1 works with a wide range of supply voltage, from 2.7v to 6v. the forward voltage of commercial white/blue led is in the range of 2.9v to 3.5v at a current level of 20ma. proper selection of the led to match the supply voltage can fully utilize the li-ion battery. for example, there is 1% ~ 3 % power left in the li-ion battery when its voltage reaches 3.275v. so a led with a forward voltage value of 3.2v can use up to 99% of the battery power under normal working condition. when the voltage of the battery drops below 3.2v, the current through the led (hence the brightness) starts to decrease. due to its uniquely designed current regulator, bl8580/1 offer low output dropout and provide superior efficiency performance over standard inductive boost type and capacitive charge pump type led driver. the en pin controls the on/off state of the device. a high level state turns on the device and a low level turns off the device, results in the low off state current. this pin needs to be terminated since a floating level of the en pin will cause the instability of the device. the sink current has a constant value of 20ma. the brightness of the led can be adjusted by controlling the duty cycle of the bl8580/1s ledn output. this can be accomplished by applying a pwm signal to the en pin. in bl8580/1, the internal power on sequence presents a delay time of 6us from ce pin to ledn pin. hence, in order to normally modulate the output of ledn in every cycle, the width of dimming signal applied ce pin have to be no less than 6us. for example, when a dimming signal of 20khz is applied, the minimum range of dimming is about 12%, that is, the average output current on each channel is 2.4 ma.
http://www.belling.com.cn - 5 - total 7 pages bl8580/1 typical characteristics quiescent current vs supply current (ta=25) 0 50 100 150 200 250 300 350 3.0 3.5 4.0 4.5 5.0 supply voltage (v) quiescent current (ua) quiescent current vs temperature (vin=3.7v) 0 50 100 150 200 250 300 350 400 450 -40 -20 0 20 40 60 80 100 120 140 temperature () quiescent current (ua) iled vs supply voltage (vin=3.7v, vf=3.2v) 10 12 14 16 18 20 22 3.3 3.4 3.5 3.6 3.7 3.8 3.9 4.0 4.1 4.2 supply voltage (v) iled (ma) iled vs ledn dropout voltage (vin=3.7v) 0 5 10 15 20 25 0.01 0.1 1 10 ledn dropout voltage (v) led current (ma) iled vs temperature (vin=3.7v) 19.7 19.8 19.8 19.9 19.9 20.0 20.0 20.1 20.1 20.2 20.2 -40 -20 0 20 40 60 80 100 120 140 temperature () iled (ma)
http://www.belling.com.cn - 6 - total 7 pages bl8580/1 mechanical data sot-23-6 (units: mm)
http://www.belling.com.cn - 7 - total 7 pages bl8580/1 sop-8
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