BL59A12/bl59s12 http://www.belling.com.cn - 1 - 8/28/2006 total 8 pages wrote by 2006 photoelectric smoke detect or ic 1. product description 1.1 basic function: BL59A12 (bl59s12) is a cmos lsi used for smoke dete ction. ultra-low power analog and digital circuits are contained in it. combined with an ir photoelectric chamber, this ic is used to detect smoke through receiving light scattered by t iny smoke particles going into the chamber. when smoke is detected, a burst of alarm sounds are generated by an external piezoelectric buzzer driven by the push-pull output of this ic. 1.2. applications: smoke detection system. 2. features: power supply range: 6v 12v average supply current: 8ua operating temperature range: -10 60 ideal for battery powered applications. 3. block diagram of this ic 4.pin assignment
BL59A12/bl59s12 http://www.belling.com.cn - 2 - 8/28/2006 total 8 pages wrote by 2006 5.pin description pin no. symbol input/output functions 1,2 c1, c2 external capacitor connection by connecting external capacitor, a voltage feedback amplifier is formed. the gain of it is determined by capacitors value. 3 detect i detecting input connect a photodiode to supply a signal to the internal comparator. 4 strobe o strobe a strobe voltage output, referenced to vdd. when output = vdd -5v, it enables other internal circuits. 5,14 vdd, gnd power supply to supply the power 6 ired o output signal to output pulse drive signal for external npn transistor which drives a ir photodiode. 7 i/o input/output it can be used to connect up to 40 detectors to make auxiliary alarm, remote alarm, auto-dialer 8,9 brass, silver o push-pull drivers output push-pull driver outputs signal to drive external buzzer to alarm, and to show various operation states. 10 feedback i feedback terminal to feed silver signal back to the push-pull output driver circuits input 11 led o output signal it is an open drain output, can drive led directly. the led can tell the detectors various operation states. 12 osc i oscillators input connected to external r and c, which determine the internal oscillators frequency. 13 r1 external r and c connecting terminal connected to external r and c, which determine the output pulse period of ired. 15 low-supply i low voltage detecting input it connected to external resistor divider between vdd and led to get a low supply alarm threshold voltage 16 test i test terminal this pin is normally low by an internal pull-down device. when it is set high, the ic enters into a simulated-smoke condition. when floating, this pin comes back to vss (low) by pull-down device. 6. function of this ic: 6.1. the variable gain photoelectric amplifier is direct ly connected to ir detector (photodiode). the amplifiers gain is determined by external capa citors c1 and c2. during standby, the amplifiers gain is at minimum. under smoke conditi on, the amplifiers gain is at medium. entering into test condition, the amplifiers gain is at maximum. additionally, under standby state, if the special supervisory circuit is activa ted to check the chambers sensitivity, the amplifiers gain is also at its maximum. 6.2. using vss as its reference, the i/o pin can be used to connect up to 40 units together. when i/o pin is used as an input, its on-chip pull- down resistor can prevent noise from entering into the unit. under smoke status, the unit activat es i/o driver to send a signal to its interconnected units to activate remote alarm.
BL59A12/bl59s12 http://www.belling.com.cn - 3 - 8/28/2006 total 8 pages wrote by 2006 6.3. display method: led (connected to led pin) flashin g combined with alarm sound, indicates a local smoke condition. only pulsating a larm sound without led flashing indicates a remote smoke condition. 7. specifications: 7.1. absolute maximum ratings(vss as reference) symbol parameter limits units vdd supply voltage -0.5 +12 c1, c2, detect -0.25 vdd+0.25 osc, low-supply trip -0.25 vdd+0.25 i/o -0.25 vdd+0.25 feedback -15 +15 vin dc input voltage test -1.0 vdd+0.25 v iin dc input current 10 ma iout dc output current 25 ma idd supply current +25/-150 ma power dissipation in still air, 5sec 1200 pd continuous 350 mw tstg storage temperature -55 125 7.2 dc electrical characteristics(ta=25 ,vss as reference, unless otherwise indicated) symbol parameters test condition vdd min. max. unit vdd power supply voltage range -- 6.0 12 v vth supply threshold voltage, low supply alarm voltage low supply trip voltage vin = vdd/3 6.5 7.8 v idd average supply current standby, (see sample figure) 12 -- 8 ua idd supply peak current strobe on, ired off (see sample figure) 12 -- 2.0 ma vil low level input voltage, i/o feedback test 9.0 9.0 9.0 1.5 2.7 7.0 v vih high level input voltage i/o feedback test 9.0 9.0 9.0 3.2 6.3 8.5 v iin input current osc, detect low supply trip feedback vin = vss or vdd vin = vss or vdd vin = vss or vdd 12 12 12 100 100 100 na iil low level input current test vin = vss 12 -1 ua iih pull-down current test i/o vin = vdd no local smoke, vin = vdd no local smoke, vin = 17v 9.0 9.0 12 0.5 25 -- 10 100 140 ua
BL59A12/bl59s12 http://www.belling.com.cn - 4 - 8/28/2006 total 8 pages wrote by 2006 vol low level output voltage, led silver, brass iout = 10ma iout = 16ma 6.5 6.5 0.6 1.0 v voh high level output voltage silver, brass iout = -16ma 6.5 5.5 - v strobe inactive, iout = -1ua active, iout = 100ua to 500ua (load regulation) - 9.0 vdd-0.1 vdd-4.4 - vdd-5.6 vout output voltage (see pin description) ired inactive, iout =-1ua active, iout =6ua (load regulation) - 9.0 - 2.25 0. 1 3.75 v local smoke, vout =4.5v 6.5 -4 -- ioh high-level output current, i/o local smoke, vout = vss (short-circuit current) 12 -- -16 ma ioz output off-state leak current, led vout = vss or vdd 12 - 1 ua vic common-mode voltage range c1, c2, detect local smoke, pushbutton test or chamber sensitivity test -- vdd -4 vdd -2 v vref internal reference voltage of smoke comparator local smoke, pushbutton test or chamber sensitivity test -- vdd-3.08 vdd-3.92 v 7.3 ac electrical characteristics (t a = 25 ,v dd = 9.0 v, component values: r1 = 100.0 k, c3 = 1500 .0 pf, r2 = 7.5 m ) symbol parameters test condition clocks min * typ ** max * unit 1/f osc oscillator period free-running sawtooth measured at pin 12 1 7.0 7.9 8.6 ms no local smoke, and no remote smoke 4096 28.8 32.4 35.2 s remote smoke, but no local smoke - extinguished t led led pulse period local smoke or pushbutton test 64 0.45 0.5 0.55 t w(led) , t w(stb) led pulse width and strobe pulse width 1 7.0 - 8.6 ms smoke test 1024 7.2 8.1 8.8 chamber sensitivity test, without local smoke 4096 28.8 32.4 35.2 t ired ired pulse period pushbutton test 128 0.9 1.0 1.1 s t w(ired) ired pulse tf* 94 116 us
BL59A12/bl59s12 http://www.belling.com.cn - 5 - 8/28/2006 total 8 pages wrote by 2006 width t r ired rise time - - 30 us t f ired fail time - - 200 us t on 0.45 0.5 0.55 t off 64 0.45 0.5 0.55 t offd silver and brass temporal modulation pulse 192 1.35 1.52 1.65 s t ch silver and brass chirp pulse period low supply or degraded chamber sensitivity 4096 28.8 32.4 35.2 s t wch silver and brass chirp pulse width 1 7.0 7.9 8.6 ms t rr rising edge on i/o to smoke alarm response time remote smoke, no local smoke - - 2! - ms smoke test 1024 7.2 8.1 8.8 chamber sensitivity test, without local smoke 4096 28.8 32.4 35.2 low supply test, without local smoke 4096 28.8 32.4 35.2 t stb strobe out pulse period pushbutton test - - 1 - s *oscillator period t (= tr + tf) is determined by t he external components r1, r2, and c3 where tr = (0.6931) r2 * c3 and tf = (0.6931) r1 * c3. the other timing characteristics are some multiple of the oscillator timing as shown in the table. **typicals are not guaranteed. time is typical - depends on what point in cycle si gnal is applied.
BL59A12/bl59s12 http://www.belling.com.cn - 6 - 8/28/2006 total 8 pages wrote by 2006 8.application sample figure r11 250k r7 10 0 k r6 47 k r14 6.8k vdd vdd vdd r1 100k r2 7.5m vdd q1 d2 ir detector r8* 6. 8k r10* 4. 7 r12 1k r13* 4.7to22 vdd test bt1 9v vdd r4* 100k r5* 2.2m a d4 visible led r3 470 1 2 3 com a d3 ir emitter d1 r9* 5k c1 47n c2 4.7n u2 buzze r c1 1 c2 2 detect 3 strobe 4 vdd 5 ired 6 7 brass 8 silver 9 freedback 10 led 11 osc 12 r1 13 vss 14 lowsupplytrip 15 test 16 c6 0.01uf c3 1500pf c5 100uf c4 47uf 9. calibration: to enter calibration mode, pin16 (test) must be bel ow vss, pulling more than 100ua continuously out of the pin for at least one osc cy cle. to exit this mode, the test pin is floated at least one osc cycle. table. configuration of pins in the calibration mod e description pin comments i/o 7 forcing this pin = vdd, places photo amps output o n pin2 when pin15= vdd, or on pin1 when pin15= vss. low-supply 15 low: normal gain of photo amplifier on pin1. high : supervisory gain on pin2. feedback 10 when pin15=low, driving it high enables gain with a hysteresis in the photo amp. osc 12 it equals to internal clock. silver 9 this pin becomes smoke comparators output. positiv e pulses indicate that smoke has been detected. a static low level in dicates no smoke. brass 8 this pin becomes the smoke integrators output. sta tic high level means two consecutive smoke detections. static low level means two no-detections.
BL59A12/bl59s12 http://www.belling.com.cn - 7 - 8/28/2006 total 8 pages wrote by 2006 10. package BL59A12
BL59A12/bl59s12 http://www.belling.com.cn - 8 - 8/28/2006 total 8 pages wrote by 2006 bl59s12
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