A5358CA

5358 PHOTOELECTRIC SMOKE DETECTOR WITH INTERCONNECT AND TIMER The A5358CA is a low-current BiCMOS circuit providing all of the required features for a photoelectric type smoke detector. This device can be used in conjunction with an infrared photoelectric chamber to sense scattered light from smoke particles. Special features are incorporated in the design to facilitate calibration and testing of the finished detector. The device is designed to comply with Underwriters Laboratories Specification UL217 and British Standard BS 5446, Part 1. A variable-gain photo amplifier can be directly interfaced to an infrared emitter/detector pair. The amplifier gain levels are determined by two external capacitors that are then internally selected depending on the operating mode. Low gain is selected during standby and timer modes. During a local alarm this low gain is increased (internally) by ~10% to reduce false triggering. High gain is used during the pushbutton test and during standby to periodically monitor the chamber sensitivity. The internal oscillator and timing circuitry keeps standby power to a minimum by sensing for smoke every 10 seconds in a 10 µs window. A special three-stage speedup sensing scheme is incorporated to minimize the time to an audible alarm and also to reduce false triggering. Also, two consecutive cycles of degraded chamber sensitivity are required for a warning signal to occur. The A5358CA is supplied in a low-cost 16-pin dual in-line plastic package. It is rated for continuous operation over the temperature range of -25°C to +75°C. Data Sheet 26110.10A C1 C2 DETECT STROBE + SUPPLY IRED I/O HORN 1 1 2 3 4 5 6 7 8 HORN DRIVER V DD LOGIC OSC. & TIMING V SS 16 15 14 13 12 11 10 9 TEST HUSH – SUPPLY TIMING RES. OSC. CAP. LED FEEDBACK HORN 2 Dwg. PC-007 ABSOLUTE MAXIMUM RATINGS (Voltages are referenced to VSS) Supply Voltage Range, VDD .................................... -0.5 V to +15 V Input Voltage Range, VIN ............................ -0.3 V to V DD + 0.3 V Input Current, IIN ................................... 10 mA Operating Temperature Range, TA ..................................... -25 °C to +75°C Storage Temperature Range, TS ................................... -55°C to +125°C CAUTION: CMOS devices have input static protection but are susceptible to damage if exposed to extremely high static electrical charges. FEATURES s s s s s s s s Interconnect Up to 50 Detectors Piezoelectric Horn Driver All Internal Low-Battery Detection Power-ON Reset Internal Timer & Control for Reduced Sensitivity Built-In Circuits to Reduce False Triggering 6 V to 12 V Operating Voltage Range ESD-Protection Circuitry on All Pins Always order by complete part number: A5358CA . 5358 PHOTOELECTRIC SMOKE DETECTOR with INTERCONNECT and TIMER FUNCTIONAL BLOCK DIAGRAM + SUPPLY V DD 5 9V BAND-GAP REFERENCE I/O 7 V DD FEEDBACK 10 9 HORN 2 8 HORN 1 LOGIC PHOTO AMP +V LOW BATTERY C1 1 TIMING RES. +V C2 2 4 V DD 6 OSCILLATOR & TIMING STROBE IRED – SUPPLY 14 V SS 15 HUSH 16 TEST Dwg. FC-006 – + DETECT 3 – + POWER-ON RESET 11 LED 13 12 OSC. CAP. 115 Northeast Cutoff, Box 15036 Worcester, Massachusetts 01615-0036 (508) 853-5000 Copyright © 1995, 1996 Allegro MicroSystems, Inc. 5358 PHOTOELECTRIC SMOKE DETECTOR with INTERCONNECT and TIMER DC ELECTRICAL CHARACTERISTICS at TA = -25°C to +75 °C*, VSS = 0 V, in typical application (unless otherwise noted). Characteristic Supply Voltage Range Operating Supply Current Symbol VDD IDD Average Standby Configured per Figure 1 During Strobe ON, IRED OFF, Configured per Figure 1 During Strobe ON, IRED ON, Configured per Figure 1 Low-Level Input Voltage VIL Test Conditions Test Pin 5 5 VDD – 12 Min. 6.0 – Limits Typ. Max. – – 12 12 Units V µA mA 5 12 – – 2.0 5 12 – – 3.0 mA 7 10 16 15 7 10 16 15 VIN = VDD, Strobe Active, Pin 12 @ VDD VIN = VDD 1, 2 9 9 9 9 9 9 9 9 12 – – – – 3.2 6.3 8.5 1.6 – – – – – – – – – – 1.5 2.7 7.0 0.5 – – – – 100 V V V V V V V V nA High-Level Input Voltage VIH Input Leakage High IIH 3, 10, 12 1, 2, 3 12 12 – – – – 100 -100 nA nA Input Leakage Low IIL VIN = VST , Strobe Active, Pin 12 @ VDD VIN = VSS 10, 12 15, 16 12 12 9 9 12 6.5 6.5 6.5 6.5 12 9 – – 0.25 20 – – – – 5.5 VDD - 0.1 VDD - 5.25 – – – – – – – 0.5 – – – -100 -1.0 10 80 140 0.6 1.0 – – – VDD - 4.75 nA µA µA µA µA V V V V V V Input Pull-Down Current IIN VIN = VDD No Local Smoke, VIN = VDD No Local Smoke, VIN = 17 V 16, 15 7 7 11 8, 9 13 8, 9 4 4 Low-Level Output Voltage V OL IO = 10 mA IO = 16 mA IO = 5 mA High-Level Output Voltage Strobe Output Voltage VOH VST IO= -16 mA Inactive IO = -1 µ A Active, IO = 100 µ A to 500 µ A Continued... 5358 PHOTOELECTRIC SMOKE DETECTOR with INTERCONNECT and TIMER DC ELECTRICAL CHARACTERISTICS, continued Test Pin 4 4 6 6 6 6 7 – 9 Limits Typ. Max. -60 0.01 – 3.1 -35 +0.40 – – – 0.1 3.35 – – – Characteristic Line Regulation Strobe Temperature Coeff. IRED Output Voltage Symbol ∆VST(∆VDD) α ST VIRED Test Conditions Active, VDD = 6 V to 12 V VDD = 6 V to 12 V Inactive IO = 1 µ A, T A = +25°C Active IO = -6 mA, TA = +25° C VDD – – 12 9 Min. – – – 2.85 – – -4.0 Units dB %/ °C V V dB %/ °C mA µA µA V V V Line Regulation IRED Temperature Coefficient High-Level Output Current ∆ VIRED(∆VDD) Active, VDD = 6 V to 12 V αIRED IOH IOZ IOZ V DD(th) VIC VREF Any Alarm Condition Any Alarm Condition VDD = 6 V to 12 V VDD = Alarm, I/O active, VO = VDD - 2 V VO = VDD VO = VSS OFF Leakage Current High OFF Leakage Current Low Low VDD Alarm Threshold Common Mode Voltage Smoke Comparator Ref. Volt. 11, 13 11, 13 5 1, 2, 3 Internal 12 12 - – – 6.9 VDD - 4 VDD - 3.7 – – 7.2 – – 1.0 -1.0 7.5 VDD - 2 VDD - 3.3 * Limits over the operating temperature range are based on characterization data. Characteristics are production tested at +25°C only. Typical values are at +25°C and are given for circuit design information only. AC ELECTRICAL CHARACTERISTICS at TA = -25°C to +75 °C*, VSS = 0 V, in typical application (unless otherwise noted). Characteristic Oscillator Period Led Pulse Period Symbol tosc tled1 tled4 tled6 tled7 Led Pulse Width tw(led) No Local or Remote Smoke Remote Smoke Only Local Smoke or Test Timer Mode, No Alarm Test Conditions Test Pin 12 11 11 11 11 11 VDD 9 9 9 9 9 9 Min. 9.4 39 None 0.60 9.67 9.5 Limits Typ. Max. 10.5 – – 0.67 10.8 – 11.5 48 – 0.74 11.8 11.5 Units ms s – s s ms Continued... 115 Northeast Cutoff, Box 15036 Worcester, Massachusetts 01615-0036 (508) 853-5000 5358 PHOTOELECTRIC SMOKE DETECTOR with INTERCONNECT and TIMER AC ELECTRICAL CHARACTERISTICS, continued. Characteristic Strobe Pulse Period Symbol tst1 tst2 tst3 tst4 tst5 tst6 Strobe Pulse Width IRED Pulse Period tw(st) tired1 tired2 tired3 tired4 tired5 tired6 IRED Pulse Width IRED Rise Time IRED Fall Time I/O to Active Delay Rising Edge on I/O to Alarm Horn Warning Pulse Period tw(ired) tr(ired) t f(ired) td(io) tr(io) thorn tw(horn) ton(horn) toff(horn) 10% to 90% 90% to 10% Local Alarm No Local Alarm Low Supply and Degraded Chamber Sensitivity Low Supply and Degraded Chamber Sensitivity Local or Remote Alarm Local or Remote Alarm No Local or Remote Smoke After 1 of 3 Valid Samples After 2 of 3 Valid Samples and During Local Alarm Remote Alarm Chamber Test, No Local Alarm Pushbutton Test, No Alarm Test Conditions No Local or Remote Smoke After 1 of 3 Valid Samples After 2 of 3 Valid Samples and During Local Alarm Remote Alarm Chamber Test or Low Supply Test, No Local Alarm Pushbutton Test, No Alarm Test Pin 4 4 4 VDD 9 9 9 Min. 9.6 2.42 1.21 Limits Typ. Max. – 2.70 1.34 11.9 2.96 1.47 Units s s s 4 4 9 9 9.67 38.9 10.8 – 11.8 47.1 s s 4 4 6 6 6 9 9 9 9 9 300 9.5 9.6 2.42 1.21 336 – – 2.70 1.34 370 11.5 11.9 2.96 1.47 ms ms s s s 6 6 6 6 6 6 7 7 8, 9 9 9 9 9 9.67 38.9 300 94 – – 10.8 – 336 – – – 0 – – 11.8 47.1 370 116 30 200 – 1.34 47.1 s s ms µs µs µs s s s 9 9 9 – – 38.9 Horn Warning Pulse Width 8, 9 9 9.5 – 11.5 ms Horn ON Time Horn OFF Time 8, 9 8, 9 9 9 – – 252 84 – – ms ms * Limits over the operating temperature range are based on characterization data. Characteristics are production tested at +25°C only. Typical values are at +25°C and are given for circuit design information only. 5358 PHOTOELECTRIC SMOKE DETECTOR with INTERCONNECT and TIMER PIN AND CIRCUIT DESCRIPTION (In Typical Application) PIN 1 (C1) A capacitor connected to this pin determines the gain of the photo amplifier during the push-to-test mode and during the chamber monitor test. A typical value for this high-gain mode is 0.047 µF but should be selected based on the photo chamber background reflections reaching the detector and the desired level of sensitivity. Ae ≈ 1+(C1/10) where C1 is in pF. Ae should not exceed 10 000. PIN 2 (C2) A capacitor connected to this pin determines the gain of the photo amplifier during standby. A typical value for this low-gain mode is 4700 pF but should be selected based on a specific photo chamber and the desired level of sensitivity to smoke. Ae ≈ 1+(C2/10) where C2 is in pF. Ae should not exceed 10 000. This gain increases by a nominal 10% after a local alarm is detected (three consecutive detections). Coupling of other signals to C2 (C1 and the DETECT inputs also) must be minimized. A resistor must be installed in series with C2. PIN 3 (DETECT) This is the input to the photo amplifier and is connected to the cathode of the photo diode. The photo diode is operated at zero bias and should have low darkleakage current and low capacitance. PIN 4 (STROBE) This output provides a strobed, regulated voltage of VDD – 5 V. The minus side of all internal and external photo amplifier circuitry is referenced to this pin. PIN 5 (VDD ) This pin is connected to the most-positive supply potential and can range from 6 V to 12 V with respect to VSS. PIN 6 (IRED) This output provides a pulsed base current for the external npn transistor, which drives the IR emitter. Its beta should be greater than 100. The IRED output is not active, to minimize noise impact, when the horn and visible LED outputs are active. PIN 7 (I/O) A connection at this pin allows multiple smoke detectors to be interconnected. If a local smoke condition occurs, this pin is driven high. As an input, this pin is sampled nominally every 1.35 seconds during standby. Any local-alarm condition causes this pin to be ignored as an input. This pin has an on-chip pull-down resistor and must be left unconnected if not used. In application, there is a series current-limiting resistor to other smoke alarms. PIN 8 (HORN1) PIN 9 (HORN2) PIN 10 (FEEDBACK) These three pins are used in conjunction with external passive components and a self-resonating piezoelectric transducer. HORN1 is connected to the piezo metal support electrode; the complementary output, HORN2, is connected to the ceramic electrode and the FEEDBACK input to the feedback electrode. A continuous modulated tone indicates either a local or remote alarm condition. A short (10 ms) chirp indicates a low-battery condition or degraded chamber sensitivity. The low-battery chirp occurs almost simultaneous with the visible LED flash. If the FEEDBACK pin is not used, it must be connected to VDD or VSS. Continued... 115 Northeast Cutoff, Box 15036 Worcester, Massachusetts 01615-0036 (508) 853-5000 5358 PHOTOELECTRIC SMOKE DETECTOR with INTERCONNECT and TIMER PIN AND CIRCUIT DESCRIPTION, continued PIN 11 (LED) This open-drain NMOS output is used to directly drive a visible LED. The load for the low-battery test is applied to this output. The low-battery test does not occur coincident with any other test or alarm signal. The LED also indicates detector status as follows (with component values as in the typical application, all times nominal): Standby Local Smoke Remote Alarm Test Mode Timer Mode - Pulses every 43 seconds. - Pulses every 0.67 second. - No pulses. - Pulses every 0.67 second. - Pulses every 10 seconds. cycle, IRED pulses every 336 ms (nominal) and amplifier gain is increased by internal selection of C1. Background reflections in the smoke chamber can be used to simulate a smoke condition. After the third IRED pulse, a successful test (three consecutive simulated smoke conditions) activates the horn drivers and the I/O pin. When the push-button is released, the input returns to VSS due to the internal pull down. After one oscillator cycle, the amplifier gain returns to normal and after three additional IRED pulses (less than one second), the device exits this mode and returns to standby. This high-to-low transition on pin 16 also resets and starts the 10 minute hush timer (timer mode). PIN 12 (OSC. CAP.) A capacitor between this pin and VDD , along with a parallel resistor, forms part of a two-terminal oscillator and sets the internal clock low time. With component values as shown, this nominal time is 11 ms and essentially the oscillator period. PIN 13 (TIMING RES.) A resistor between this pin and OSC. CAP. (pin 12) is part of the two-terminal oscillator and sets the internal clock high time, which is also the IRED pulse width. With component values as shown, this nominal time is 105 µs. PIN 14 (VSS) This pin is connected to the most negative supply potential (usually ground). PIN 15 (HUSH) This input pin serves two purposes in normal operation. It serves as an enable for the internal 10-minute (nominal) timer and also as the reference for the smoke comparator during the timer mode. This reference is established by a resistive divider between VDD and STROBE (RX1 and RX2). This allows the detector to have a different sensitivity set point during the timer mode. If the timer mode is not used, this pin can be left open or connected to VSS, which disables this mode. PIN 16 (TEST) This pin has an internal pull-down device and is used to manually invoke two test modes and a Timer Mode. The Push-to-Test Mode is initiated by a high logic level on this pin (usually the depression of a normally open push-button switch to VDD). After one oscillator Pin Name I/O Pin No. Configuration 7 Disabled as an output. A logic high on this pin places the photo amplifier output on pin 1 or pin 2 as determined by pin 15. The amplifier output appears as pulses. If the I/O pin is high, this pin controls the amplifier gain capaci tor. If pin 15 is low, normal gain is selected and the amplifier output is on pin 1. If pin 15 is high, supervisory gain is selected and the amplifier output is on pin 2. If pin 7 is high and pin 15 is low (normal gain), taking this pin to a high logic level increases the amplifier gain by ~10% (hysteresis). This pin may be driven by an external clock source. Driving this pin low and high drives the internal clock low and high. The external RC network may remain intact. HUSH 15 FEEDBACK 10 OSC. CAP. 12 5358 PHOTOELECTRIC SMOKE DETECTOR with INTERCONNECT and TIMER PIN AND CIRCUIT DESCRIPTION, continued The Diagnostic Test Mode is initiated by pulling this pin below VSS and continuously sourcing 400 µA from the pin for at least one clock cycle on the OSC. CAP. pin. This mode is used to facilitate calibration and test of the IC and the assembled detector. In this mode, certain device pins are reconfigured as described below. In this mode, the IRED pulse rate is increased to one every OSC. CAP. cycle and the STROBE pin is always active. To exit this mode, the test pin is floated for at least one OSC. CAP. cycle. Pin Name HORN1 Pin No. Configuration 8 This pin is reconfigured as the smoke integrator output. Three consecutive smoke detections will cause this pin to go high and three consecutive nosmoke detections cause this pin to go low. This pin becomes a low-battery indicator. The open-drain NMOS output is normally OFF. If VDD falls below the lowbattery threshold, the output turns ON. LED 11 TYPICAL APPLICATION CONNECT FOR TIMER MODE OR "HUSH" OPERATION VDD 8.2kΩ PUSH TO TEST CONNECT FOR NON-TIMER MODE OPERATION RX1 C1 1 C2 560Ω 2 3 200kΩ SMOKE CHAMBER 5kΩ 16 15 VSS OSC. & TIMING V DD LOGIC 14 13 12 11 1000pF 220kΩ 10 HORN DRIVER 9 100kΩ 1500pF 22µF + 9V RX2 4.7kΩ 4 5 1kΩ + 100µF 22Ω 6 7 8 220Ω TO/FROM OTHER UNITS Dwg. EC-006 115 Northeast Cutoff, Box 15036 Worcester, Massachusetts 01615-0036 (508) 853-5000 330Ω 100kΩ 10MΩ 5358 PHOTOELECTRIC SMOKE DETECTOR with INTERCONNECT and TIMER STANDBY TIMING DIAGRAM (not to scale) OSC. CAP (PIN 12) t osc INTERNAL CLOCK t ired IRED (PIN 6) t w(ired) STROBE (PIN 4) t w(st) t st t led LED (PIN 11) t w(led) SAMPLE SMOKE WARNING CHIRP t horn HORN ENABLE t w(horn) NO LOW SUPPLY CHAMBER SENSITIVITY NORMAL LOW SUPPLY OR DEGRADED SENSITIVITY WARNING CHIRPS ARE OFFSET Dwg. WC-008 5358 PHOTOELECTRIC SMOKE DETECTOR with INTERCONNECT and TIMER LOCAL ALARM TIMING DIAGRAM (not to scale) t w(ired) 90% t f(ired) t ired3 IRED (PIN 6) t st3 STROBE (PIN 4) t w(led) LED (PIN 11) t led1 (NO PULSES) t led6 t w(st) t st4 t st6 10% 10% t ired4 t ired6 I/O (PIN 7) (AS OUTPUT) (AS INPUT) (AS OUTPUT) t on(horn) HORN ENABLE t off(horn) t r(io) t on(horn) t off(horn) LOCAL SMOKE (REMOTE SMOKE = DON'T CARE) NO SMOKE REMOTE SMOKE (NO LOCAL SMOKE) 3RD STROBE WITHOUT SMOKE TEST 3RD STROBE WITH SMOKE Dwg. WC-009 115 Northeast Cutoff, Box 15036 Worcester, Massachusetts 01615-0036 (508) 853-5000 5358 PHOTOELECTRIC SMOKE DETECTOR with INTERCONNECT and TIMER Dimensions in Inches (controlling dimensions) 0.014 0.008 16 9 0.430 0.280 0.240 MAX 0.300 BSC 1 0.070 0.045 0.100 0.775 0.735 BSC 8 0.005 MIN 0.210 MAX 0.015 MIN 0.150 0.115 0.022 0.014 Dwg. MA-001-16A in Dimensions in Millimeters (for reference only) 0.355 0.204 16 9 10.92 7.11 6.10 MAX 7.62 BSC 1 1.77 1.15 2.54 19.68 18.67 BSC 8 0.13 MIN 5.33 MAX 0.39 MIN 3.81 2.93 0.558 0.356 Dwg. MA-001-16A mm NOTES: 1. Lead thickness is measured at seating plane or below. 2. Lead spacing tolerance is non-cumulative. 3. Exact body and lead configuration at vendor’s option within limits shown. 5358 PHOTOELECTRIC SMOKE DETECTOR with INTERCONNECT and TIMER SAFETY & SECURITY ICs SELECTION GUIDE Part Number A3054KU/SU A5347CA A5348CA A5349CA A5350CA A5358CA Function Multiplexed Two-Wire Hall-Effect Sensor Ionization-Type Smoke Detector with Interconnect and Timer Ionization-Type Smoke Detector with Interconnect, Timer, and Reverse-Battery Protection Ionization-Type Smoke Detector with Interconnect and Timer for AC Line Operation Ionization-Type Smoke Detector with Interconnect and Reverse-Battery Protection Photoelectric-Type Smoke Detector with Interconnect and Timer Allegro MicroSystems, Inc. reserves the right to make, from time to time, such departures from the detail specifications as may be required to permit improvements in the design of its products. The information included herein is believed to be accurate and reliable. However, Allegro MicroSystems, Inc. assumes no responsibility for its use; nor for any infringements of patents or other rights of third parties which may result from its use. 115 Northeast Cutoff, Box 15036 Worcester, Massachusetts 01615-0036 (508) 853-5000