BL59A12/BL59S12 PHOTOELECTRIC SMOKE DETECTOR IC 1. Product description 1.1 Basic function: BL59A12 (BL59S12) is a CMOS LSI used for smoke detection. 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 tiny 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 http://www.belling.com.cn -1- Total 8 Pages 8/28/2006 Wrote by 2006 BL59A12/BL59S12 5.Pin description Pin Symbol No. Input/output Functions External capacitor connection 1,2 C1, C2 3 DETECT I Detecting input 4 STROBE O Strobe 5,14 VDD, GND 6 IRED 7 I/O 8,9 BRASS, SILVER O Push-pull driver’s output 10 FEEDBACK I Feedback terminal 11 LED O Output signal 12 OSC I Oscillator’s input 13 R1 15 LOW-SUPPLY I Low voltage detecting input 16 TEST I Test terminal Power supply O Output signal Input/output External R and C connecting terminal By connecting external capacitor, a voltage feedback amplifier is formed. The gain of it is determined by capacitor’s value. Connect a photodiode to supply a signal to the internal comparator. A strobe voltage output, referenced to VDD. When output = VDD -5V, it enables other internal circuits. To supply the power To output pulse drive signal for external NPN transistor which drives a IR photodiode. It can be used to connect up to 40 detectors to make auxiliary alarm, remote alarm, auto-dialer… Push-pull driver outputs signal to drive external buzzer to alarm, and to show various operation states. To feed ‘silver’ signal back to the push-pull output driver circuit’s input It is an open drain output, can drive LED directly. The LED can tell the detector’s various operation states. Connected to external R and C, which determine the internal oscillator’s frequency. Connected to external R and C, which determine the output pulse period of IRED. It connected to external resistor divider between VDD and LED to get a low supply alarm threshold voltage 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 directly connected to IR detector (photodiode). The amplifier’s gain is determined by external capacitors C1 and C2. During standby, the amplifier’s gain is at minimum. Under smoke condition, the amplifier’s gain is at medium. Entering into test condition, the amplifier’s gain is at maximum. Additionally, under standby state, if the special supervisory circuit is activated to check the chamber’s sensitivity, the amplifier’s 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 activates I/O driver to send a signal to its interconnected units to activate remote alarm. http://www.belling.com.cn -2- Total 8 Pages 8/28/2006 Wrote by 2006 BL59A12/BL59S12 6.3. Display method: LED (connected to LED pin) flashing combined with alarm sound, indicates a LOCAL SMOKE condition. Only pulsating alarm sound without LED flashing indicates a REMOTE SMOKE condition. 7. Specifications: 7.1. Absolute maximum ratings(VSS as reference) Symbol Parameter -0.5 ～ +12 C1, C2, Detect OSC, low-supply trip I/O -0.25 ～Vdd+0.25 -0.25 ～Vdd+0.25 -0.25 ～Vdd+0.25 Feedback -15 ～+15 Test DC input current DC output current Supply current Power dissipation in still air, 5Sec Continuous Storage temperature -1.0 ～Vdd+0.25 ±10 ±25 +25/-150 1200 350 -55 ～125 VIN DC input voltage PD TSTG Units Supply voltage VDD IIN IOUT IDD Limits V mA mA mA mW ℃ 7.2 DC Electrical characteristics(Ta=25℃ ℃,VSS as reference, unless otherwise indicated) Symbol VDD Parameters Power supply voltage range VTH Supply threshold voltage, Low supply alarm voltage IDD Average supply current iDD Supply peak current VIL VIH Test condition Low supply trip voltage VIN = VDD/3 Standby, (See sample figure) Strobe on, IRED off (See sample figure) Low level input voltage, I/O Feedback Test High level input voltage I/O Feedback Test VDD Min. Max. Unit -- 6.0 12 V 6.5 7.8 V 12 -- 8 uA 12 -- 2.0 mA 1.5 2.7 7.0 V 9.0 9.0 9.0 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 IIL Low level input current TEST VIN = VSS 12 -1 Pull-down current Test I/O VIN = VDD No local smoke, VIN = VDD No local smoke, VIN = 17V 9.0 9.0 12 IIH http://www.belling.com.cn -3- Total 8 Pages 0.5 25 -- nA uA 10 100 140 uA 8/28/2006 Wrote by 2006 BL59A12/BL59S12 VOL VOH Low level output voltage, LED Silver, Brass High level output voltage Silver, Brass Strobe VOUT Output voltage (See pin description) IRED IOH High-level output current, I/O IOZ Output off-state leak current, LED VIC Common-mode voltage range C1, C2, Detect VREF Internal reference voltage of smoke comparator IOUT = 10mA IOUT = 16mA 6.5 6.5 IOUT = -16mA Inactive, IOUT = -1uA Active, IOUT = 100uA to 500uA (load regulation) Inactive, IOUT =-1uA Active, IOUT =6uA (load regulation) Local smoke, VOUT =4.5V Local smoke, VOUT = VSS (short-circuit current) VOUT = VSS or VDD Local smoke, Pushbutton test or chamber sensitivity test Local smoke, pushbutton test or chamber sensitivity test 0.6 1.0 6.5 5.5 - VDD-0.1 9.0 VDD-4.4 V - V Vdd-5.6 V 9.0 2.25 0. 1 3.75 6.5 -4 -- 12 -- -16 12 - ±1 uA -- VDD -4 VDD -2 V -- VDD-3.08 VDD-3.92 V mA 7.3 AC ELECTRICAL CHARACTERISTICS (TA= 25℃,VDD = 9.0 V, Component Values: R1 = 100.0 K, C3 = 1500.0 pF, R2 = 7.5 MΩ) Symbol 1/fosc tLED tw(LED), tw(stb) tIRED tw(IRED) Parameters Oscillator Period LED Pulse Period Test condition Free-Running Sawtooth Measured at Pin 12 No Local Smoke, and No Remote Smoke Remote Smoke, but No Local Smoke Local Smoke or Pushbutton Test IRED Pulse Period IRED Pulse http://www.belling.com.cn ** * Min Typ Max 1 7.0 7.9 8.6 ms 4096 28.8 32.4 35.2 s - Unit Extinguished 64 0.45 0.5 0.55 1 7.0 - 8.6 1024 7.2 8.1 8.8 4096 28.8 32.4 35.2 s 128 Tf* 0.9 94 1.0 1.1 116 us LED Pulse Width and Strobe Pulse Width Smoke Test Chamber Sensitivity Test, without Local Smoke Pushbutton Test * Clocks -4- Total 8 Pages ms 8/28/2006 Wrote by 2006 BL59A12/BL59S12 tr tf ton toff toffd tCH twCH tRR tstb Width IRED Rise Time IRED Fail Time Silver and Brass Temporal Modulation Pulse Silver and Brass Chirp Pulse Period Silver and Brass Chirp Pulse Width Rising Edge on I/O to Smoke Alarm Response Time Strobe Out Pulse Period - 192 0.45 0.45 1.35 us us 0.5 0.5 1.52 30 200 0.55 0.55 1.65 4096 28.8 32.4 35.2 s 1 7.0 7.9 8.6 ms - - 2! - ms 1024 7.2 8.1 8.8 4096 28.8 32.4 35.2 64 Low Supply or Degraded Chamber Sensitivity Remote Smoke, No Local Smoke Smoke Test Chamber Sensitivity Test, without Local Smoke Low Supply Test, Without Local Smoke Pushbutton Test s s 4096 28.8 32.4 35.2 - - 1 - *Oscillator period T (= Tr + Tf) is determined by the 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 signal is applied. http://www.belling.com.cn -5- Total 8 Pages 8/28/2006 Wrote by 2006 BL59A12/BL59S12 8.Application sample figure VDD VDD R8* D1 C4 6. 8k R14 1 6.8K R11 2 250K R10* D2 3 4. 7 IR Detector R12 D3 1k A VDD IR Emitter C5 100uF R7 47n C1 C2 4.7n 5k VDD 9V TEST R9* VDD BT1 47uF R13* 4.7to22 Q1 4 5 6 7 8 C1 Test C2 LowSupplyTrip Detect Vss Strobe R1 Vdd Osc IRED Ｉ／Ｏ LED Freedback Brass SILVER 3 2 1 10 0 K 16 15 13 12 11 10 VDD R2 14 7.5M R1 C3 R6 100K R3 470 D4 A 9 Visible LED U2 R4* 100K 47 K 1500pf C6 0.01uf R5* 2.2M BUZZE R com 9. Calibration: To enter calibration mode, pin16 (TEST) must be below VSS, pulling more than 100uA continuously out of the pin for at least one OSC cycle. To exit this mode, the TEST pin is floated at least one OSC cycle. Table. Configuration of pins in the calibration mode Description PIN Comments Forcing this pin = VDD, places photo amp’s output on pin2 when pin15= I/O 7 VDD, or on pin1 when pin15= VSS. Low: normal gain of photo amplifier on pin1. Low-supply 15 High: supervisory gain on pin2. When pin15=low, driving it high enables gain with a hysteresis in the Feedback 10 photo amp. OSC 12 It equals to internal clock. This pin becomes smoke comparator’s output. Positive pulses indicate Silver 9 that smoke has been detected. A static low level indicates no smoke. This pin becomes the smoke integrator’s output. Static high level means Brass 8 two consecutive smoke detections. Static low level means two no-detections. http://www.belling.com.cn -6- Total 8 Pages 8/28/2006 Wrote by 2006 BL59A12/BL59S12 10. Package BL59A12 http://www.belling.com.cn -7- Total 8 Pages 8/28/2006 Wrote by 2006 BL59A12/BL59S12 BL59S12 http://www.belling.com.cn -8- Total 8 Pages 8/28/2006 Wrote by 2006