M75210

M75210 MOSDESIGN | Alldatasheet

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COST-EFFECTIVE PHOTOELECTRIC SMOKE DETECTOR SMOKE DETECTOR M75210 一華半導體股份有限公司 MOSDESIGN SEMICONDUCTOR CORP. GENERAL DESCRIPTION The M75210 is a very low-power IC providing all of the re quired features for a photoelectric type smoke detector. It is designed for operate at supply voltage as low as 2.7V and suited to 3V Lithium battery powered application. 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. During a local alarm this low gain is increased (internally) by ~ 10% to reduce false triggering. High gain is used during the push-button 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 100 μs window.

FEATURES

‧ Operating voltage range 2.7V ~ 5V ‧ Local or Remote Smoke Alarm output. ‧ Low-Battery Trip Point Set Externally ‧ Power-on Reset. ‧ Built-in circuits to reduce false triggering. ‧ Average Supply Current: 4μA @VDD=3.0V ‧ ESD-Protection circuitry on all pins.

APPLICATIONS

‧ Smoke detector. PIN ASSIGNMENT Pb M75210P DETECT VDD IRED I/O TEST HORN LED OSCH VSS OSCR TRIP OPT OSCC 1 16 8 9 STROBE

COST-EFFECTIVE PHOTOELECTRIC SMOKE DETECTOR SMOKE DETECTOR M75210 一華半導體股份有限公司 MOSDESIGN SEMICONDUCTOR CORP. PIN AND CIRCUIT DESCRIPTION Pin No Pin Name Description 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. 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 4700pF but should be selected based on a s pecific photo chamber and the desired level o f sensitivity to smoke. Ae ≒ 1 + ( C2 / 10 ) where C2 is in pF. Ae should not exceed 10,000. 3 DETECT This is the input to the photo amplifier and is connected to the anode of the photo diode. The photo diode is operated at zero bias and should have low dark leakage current and low capacitance.

4 STROBE

This output provides a strobed , regulated voltage of 2V . The plus side of all internal and external photo amplifier circuitry is referenced to this pin. 5 VDD This pin is connected to the most-positive supply potential and can range from 2.7V to 5V with respect to VSS.

6 IRED

This output provides a pulsed base current for the external NPN transistor, which drives the IR emitter. The NPN transistor’s beta should be greater than 100. To minimize noise impact, the IRED output is not active when the horn and visible LED outputs are active.

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 also 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. 8 OSCH Low-cost RC oscillator and sets the internal alarm frequency. 9 HORN A continuous modulated tone indicates either a local or remote alarm condition. A short ( 10ms ) chirp indicates a low-battery chirp occurs almost simultaneous with the visible LED flash. 10 OPT OPT select stand-by Led flash cycle , when connect to VSS=43 second , when connect to VDD=8 second

11 LED

This open-drain NMOS output is used to directly drive a visible LED. The LED also indicates detector status as follows (with component values as in the typical application , all times nominal)： Standby ─ Pulses every 43 seconds. Test Mode ─ Pulses every 0.67 seconds. Local Smoke ─ Pulses every 0.67 seconds. Remote Alarm ─ No pulses.

12 OSCC

A capacitor between this pin and VDD, along with a paralle l 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. 13 OSCR A resistor between this pin and OSCC (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 105μs . 14 VSS This pin is connected to the most negative supply potential (usually ground).

15 TRIP

This pin is connected to an external voltage which determines the low-supply alarm threshold. The trip voltage is obtained through a resistor divider connected between the VDD and LED pins. The low-supply alarm threshold voltage ( in volts ) ≒ ( 1.4*R13/R14 ) + 1.4 where R13 and R14 are in the same units.

16 TEST

This pin has an internal pull-down device and is used to manually invoke a test 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 cycle, IRED pulse 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 second IRED pulse , a successful test ( two 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 two additional I RED pulse ( less than one second ) , the device exits this mode and returns to standby.

COST-EFFECTIVE PHOTOELECTRIC SMOKE DETECTOR SMOKE DETECTOR M75210 一華半導體股份有限公司 MOSDESIGN SEMICONDUCTOR CORP. FUNCTIONAL BLOCK DIAGRAM LOCAL ALARM TIMING DIAGRAM ( NOT TO SCALE )： 90% 10% tw(ired) 10% tf(ired) tired4 tired6 tw(st) tst2 tst4 tw(led) tled1 (NO PULSES) tled4 (AS OUTPUT) (AS INPUT) (AS OUTPUT) ton (horn)ton(horn) toff(horn) tr(io) toff(horn) NO SMOKE REMOTE SMOKE

3 STROBE WITH SMOKE

3 STROBE WITHOUT SMOKE

(PIN 6) STROBE (PIN 4) LED (PIN 11) I/O (PIN 7) ( NO LOCAL SMOKE ) HORN ENABLE LOCAL (REMOTE SMOKE = DON’T CARE) I/O LOGIC OSCILLATOR & TIMING POWER-ON RESET PHOTO AMP VDD VDD DETECT IRED VSS LED OSCH OSCR

10 OPT

9 HORN

COST-EFFECTIVE PHOTOELECTRIC SMOKE DETECTOR SMOKE DETECTOR M75210 一華半導體股份有限公司 MOSDESIGN SEMICONDUCTOR CORP. STANDBY TIMING DIAGRAM ( NOT TO SCALE )： HORN MODULATION PATTERN LOW SUPPLY OR DEGRADED SENSITIVITY WARNNING CHIRPS ARE OFFSET tOSC tw(st) tled tst tW(led) CHIRP thorn tw(horn) NO LOW SUPPLY CHAMBER SENSITIVITY NORMAL OSCC (PIN 12) INTERNAL CLOCK IRED (PIN 6) STROBE (PIN4) LED (PIN 11) SAMPLE SMOKE HORN ENABLE tired tW(ired) WARNING 84mS 336mS 84mS 336mS 84mS 336mS 84mS 336mS

COST-EFFECTIVE PHOTOELECTRIC SMOKE DETECTOR SMOKE DETECTOR M75210 一華半導體股份有限公司 MOSDESIGN SEMICONDUCTOR CORP. ABSOLUTE MAXIMUM RATING D C E L E C T R I C A L C H A R A C T E R I S T I C S ( TA= -25℃ ~ 75 ℃ ) Characteristics Sym. Pin V DD Min. Typ. Max. Unit Conditions Supply V oltage V DD — 2.7 3 5.0 V 3 — — 4.5 μA Average Standby 3 — — 2.0 mA During Strobe ON, I RED OFF Operating Supply Current IDD 3 — — 3.0 mA During Strobe ON, I RED ON Low-Level Input V oltage VIL 7 3 — — 1.0 V High-Level Input V oltage VIH 7 3 2.0 — — V 12 3 — — 100 nA V IN=VDD, Strobe Active, Pin12 @VDD Input Leakage High I IH 15 3 — — 100 nA V IN=VDD 12 3 — — -100 nA V IN=VST , Strobe Active, Pin12 @VDD Input Leakage Low I IL 7 3 — — 140 μA No Local Smoke ,VIN=17V(@VDD=12V) 11 3 — — 0.6 V I O = 10mA Low-Level Output V oltage V OL 13 3 — 0.5 — V I O = 5mA 3 — — VSS+0.1 V Inactive , IO = -1μA Strobe Output V oltage V ST 4 3 1.7 — 2.3 V Active , IO = 100μA to 500μA 3 — — 0.1 V Inactive , IO =1mA , TA = +25℃ IRED Output V oltage V IRED 6 3 0.9 1.2 1.4 V Active , IO = -6mA , TA = +25℃ Line Regulation ΔVIRED(ΔVDD) — — -35 — dB Active, VDD= 4V to 6V High-Level Output V oltage IOH 7 3 -4.0 — — mA V DD= Alarm, I/O active, VO= VDD-2V OFF Leakage Current High I OZ 11 3 — — 1.0 μA VO= VDD OFF Leakage Current Low I OZ 11 3 — — -1.0 μA VO= VSS Low VDD Alarm Threshold V DD (th) — 2.55 2.7 2.85 V Common Mode V oltage V IC 1, 2, 3 — 1.0 — 2.0 V Any Alarm Condition * Limits over the operating temperature range are based on characterization data. Characteristics are production tested at +25℃. Typical values are at +25 ℃and are given for circuit design information only. Parameter Sym. Rating Unit Supply V oltage Range V DD -0.5 ~ 5 V Input V oltage Range V IN -0.3 to V DD + 0.3 V Input Current I IN 10 mA Operating Temperature Range T A -10 ~ 60 ℃ Storage Temperature Range T S -55 to 125 ℃

COST-EFFECTIVE PHOTOELECTRIC SMOKE DETECTOR SMOKE DETECTOR M75210 一華半導體股份有限公司 MOSDESIGN SEMICONDUCTOR CORP. A C E L E C T R I C A L C H A R A C T E R I S T I C S ( TA= -25℃ ~ 75 ℃ ) Characteristics Sym. V DD Min. Typ. Max. Unit Conditions Oscillator Period T OSC 3 9.4 10.5 11.5 ms TLED1 3 38.9 43 47.1 s No Local or Remote Smoke TLED2 3 None — — s Remote Smoke only Led Pulse Period TLED3 3 0.6 0.67 0.74 s Local Smoke or Test Led Pulse Width TW (LED) 3 9.5 10.5 11.5 ms TST1 3 9.6 10.5 11.9 s No Local or Remote Smoke TST2 3 9.6 10.5 11.9 s Remote Alarm TST3 3 38.9 43 47.1 s Chamber Test or Low Supply Test ,No Local Alarm Strobe Pulse Period TST4 3 300 336 370 ms Pushbutton Test , No Alarm Strobe Pulse Width T W (ST) 3 9.5 10.5 11.5 ms TIRED1 3 9.6 10.5 11.9 s No Local or Remote Smoke TIRED2 3 9.6 10.5 11.9 s Remote Alarm TIRED3 3 38.9 43 47.1 s Chamber Test , No Local Alarm IRED Pulse Period TIRED4 3 300 336 370 ms Pushbutton Test , No Alarm IRED Pulse Width T W (IRED) 3 94 104 116 μs IRED Rise Time Tr(IRED) 3 — — 30 μs 10% to 90% IRED Fall Time Tf (IRED) 3 — — 200 μs 90% to 10% I/O to Active Delay Td (IO) 3 — 0 — s Local Alarm Rising Edge on I/O to Alarm Tr (IO) 3 — — 1.65 s No Local Alarm Horn Warning Pulse Period THORN 3 38.9 43 47.1 s Low Supply and Degraded Chamber Sensitivity Horn Warning Pulse Width T W (HORN) 3 9.5 10.5 11.5 ms Low Supply and Degraded Chamber Sensitivity Horn ON Time T ON (HORN) 3 300 336 370 ms Local or Remote Alarm Horn OFF Time T OFF1 (HORN) 3 75 84 93 ms Local or Remote Alarm * Limits over the operating temperature range are based on characterization data. Characteristics are production tested at +25℃. Typical values are at +25 ℃and are given for circuit design information only.

COST-EFFECTIVE PHOTOELECTRIC SMOKE DETECTOR SMOKE DETECTOR M75210 一華半導體股份有限公司 MOSDESIGN SEMICONDUCTOR CORP. APPLICATION DIAGRAM STAND-ALONE： * C2 and R7 are used for coarse sensitivity adjustment. Typical values are shown. NET WORK： * C2 and R7 are used for coarse sensitivity adjustment. Typical values are shown. * All specs and applications shown above subject to change without prior notice. (以上電路及規格僅供參考,本公司得逕行修正) Q1R14 STROBE M75210P 1 16 VDD 200K 10K DETECT 100K 4.7~22 1000pF 4700pF OUT IRED OSCR VSS LED OSCC 100uF OPT SMOKE CHAMBER VDD = 5V 100u C1815 5.1V 4.7K 2.2M 22uF 36V/1W IN4004 X 4 LINE IN 200/1W IN4004 470 TEST TRIP HORN OSCH 5.6K 8.2K C5 10M 1500pF R10 R12 R11 R13 R14 104 220 C945 D2 BUZZER M75210P 11 6 VDD VDD 200K 10K STROBE DETECT 3.0V 100K TEST 1500pF 4.7~22 1000pF TO/FROM UNITS OTHER 4700pF R12 I/O IRED OSCH OSCR VSS RLED OSCC SMOKE CHAMBER 2.2uF TEST TO PUSH HORN 330 TRIP OPT 100K 56K 270P 5.6K 8.2K C5 10M R10 R13 R14 300K 220 R11 104 470 R15 CR2450 Lithium

COST-EFFECTIVE PHOTOELECTRIC SMOKE DETECTOR SMOKE DETECTOR M75210 一華半導體股份有限公司 MOSDESIGN SEMICONDUCTOR CORP. CALIBRATION To facilitate checking the sensitivity and calibrating smoke detectors, the M75210 can be placed in a calibration mode. In this mode, certain device pins are controlled/reconfigured as shown in Table 1. To place the part in the calibration mode, pin 16 (Test) must be middle of VDD for at least one cycle on the OSC pin. In the calibration mode, the IRED pulse happens at every clock cycle and strobe is always on (active high). Also, Low Battery and supervisory tests are disabled in this mode. Table 1 Configuration of Pins in the Calibration Mode Description Pin Comment I/O 7 Disabled as an output. Forcing this pin high places the photo amp output on pin 1 or 2, as determined by Low-Supply Trip. The amp’s output appears as pulses and is referenced to VSS. Trip 15 If the I/O pin is high, pin 15 controls which gain capacitor is used. Low: normal gain, amp output on pin 1.High: supervisory gain, amp output on pin 2. OPT 10 Driving this input low enables hysteresis (10% gain increase) in the photo amp; pin 15 must be low. OSCC 12 Driving this input high brings the internal clock high. Driving the input low brings the internal clock low. If desired, the RC network for the oscillator may be left intact; this allows the oscillator to run similar to the normal mode of operation. Horn 8 This pin becomes the smoke comparator output. When the OSC pin is toggling, positive pulses indicate that smoke has been detected. A static low level indicates no smoke. OSCH 9 This pin becomes the smoke integrator output. That is, two consecutive smoke detections ON (static high level) and two consecutive no-detections for .off. (static low level). RECOMMENDED PCB LAYOUT Notes：Illustration is bottom view of layout using a Dip. Top view for SOIC layout is mirror image. Optional potentiometer R2 is not illustrated drawing is not to scale. Leads on D2, R6, R1, and R3 and their associated traces must be kept as short as possible. This practice minimizes noise pick-up. Pin 3 mu st be decoupled from all other traces. R5 C2 PIN16 PIN1 PIN9 PIN8 DO NOT RUN ANY ADDITIONAL TRACES IN THIS REGION MOUNTED IN CHAMBER