1/10 2006-01-25 photoelectric smoke detector with interconnect smoke detector M75010 ?A?w??? mosdesign semiconductor corp. general description the M75010 is a very low-power ic 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. 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 trigger ing. high gain is used during the push-button test and during standby to periodically monitor the chamber sensitivity. features ? interconnect up to 50 detectors. ? piezoelectric horn driver. ? all internal low-battery detection. ? power-on reset. ? built-in circuits to reduce false triggering. ? 6v to 12v operating voltage range. ? esd-protection circuitry on all pins. applications ? smoke detector. pin assignment c1 c2 detect strobe vdd ired i/o test horn2 led horn1 vss oscr trip feedback oscc 116 89 M75010p
2/10 2006-01-25 photoelectric smoke detector with interconnect smoke detector M75010 ?A?w??? mosdesign semiconductor corp. absolute maximum rating parameter sym. rating unit supply voltage range v dd -0.5 ~ 13 v input voltage range v in -0.3 to v dd + 0.3 v input current i in 10 ma operating temperature range t a -25 ~ 75 storage temperature range t s -55 to 125 pin and circuit description pin no pin name description 1c1 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 f but should be selected based on the photo chamber background reflections reaching the detector and the desired level o f sensitivity. ae P 1 + ( c1 / 10 ) where c1 is in pf. ae should not exceed 10,000. 2c2 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 P 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 connect ed to the cathode of the photo diode. the photo diode is operated at zero bias and should have low darkleakage current and low capacitance. 4strobe this output provides a strobed , regulated voltage of vdd-5v. the minus side of all internal and external photo amplifier circuitry is referenced to this pin. 5vdd this pin is connected to the most-positive supply potential and can range from 6v to 12v with respect to vss. 6ired this output provides a pulsed base current for the extern al npn transistor , which drives the ir emitter. its beta should be greater than 100. the ired output is not active , to minimize noi se impact , when the horn and visible led outputs are active. 7i/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. an internal nmos device acts as a charge dump to ai d in applications involving a large ( distributed ) capacitance. the charge dump is activat ed at the end of local or test al arm. 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 horn1 9 horn2 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 el ectrode and the feedback input to the feedback electrode. 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. if the feedback pin is not used , it must be connected to vdd or vss.
3/10 2006-01-25 photoelectric smoke detector with interconnect smoke detector M75010 ?A?w??? mosdesign semiconductor corp. 11 led this open-drain nmos output is used to directly dr ive a visible led. 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 pulses every 43 seconds. local smoke pulses every 0.67 seconds. remote alarm no pulses. test mode pulses every 0.67 seconds. 12 oscc 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. 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 i red pulse width. with component values as shown , this nominal time is 105 s . 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 ) P ( 5r15/r14 ) + 5 where r6 and r7are 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, i red 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 third i red 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 i red pulse ( less than one second ) , the device exits this mode and returns to standby.
4/10 2006-01-25 photoelectric smoke detector with interconnect smoke detector M75010 ?A?w??? mosdesign semiconductor corp. local alarm timing diagram ( not to scale ) t ired3 90% 10% t w ( ired ) 10% t f(ired) t ired4 t ired6 t st3 t w ( st ) t st4 t st6 t w(led) t led1 (no pulses) t led6 ( as output ) (as input) (as output) t on (horn) t on ( horn ) t off(horn) t r(io) t off(horn) no smoke remote smoke 3 strobe with smoke test 3 strobe without ired (pin 6) strobe (pin 4) led (pin 11) i/o (pin 7) ( no local smoke ) horn enable local smoke (remote smoke = don?t care)
5/10 2006-01-25 photoelectric smoke detector with interconnect smoke detector M75010 ?A?w??? mosdesign semiconductor corp. standby timing diagram ( not to scale ) t osc t w(st) t led t st t w(led) chirp t horn t w(horn) low supply or degraded sensitivity warnning chirps are offset no low supply chamber sensitivity normal oscc (pin 12) internal clock ired (pin 6) strobe (pin4) led (pin 11) sample smoke horn enable t ired t w(ired) warning
6/10 2006-01-25 photoelectric smoke detector with interconnect smoke detector M75010 ?A?w??? mosdesign semiconductor corp. functional block diagram 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 logic + - + - band-gap reference oscillator & timing power-on reset low battery photo amp vdd vdd detect i/o feedback strobe ired vss c1 c2 horn 2 vdd led horn 1 oscc. oscr test trip +v +v
7/10 2006-01-25 photoelectric smoke detector with interconnect smoke detector M75010 ?A?w??? mosdesign semiconductor corp. dc electrical characteristics (ta=-25 ~ 75 ) characteristics sym. pin v dd min. typ. max. unit conditions supply voltage v dd 6.0 12 v 12 12 a average standby 12 2.0 ma during strobe on , i red off operating supply current i dd 12 3.0 ma during strobe on , i red on 79 1.5 v 10 9 2.7 v 16 9 7.0 v low-level input voltage v il 15 9 0.5 v 79 3.2 v 10 9 6.3 v 16 9 8.5 v high-level input voltage v ih 15 9 1.6 v 12 12 100 na v in =v dd , strobe active ,pin12 @v dd input leakage high i ih 15 12 100 na v in =v dd 12 12 -100 na v in =v st , strobe active ,pin12 @v dd 15 12 -100 na input leakage low i il 16 12 -1.0 a v in =v ss 16 9 0.25 10 a v in =v dd ( @ v dd =9v) 79 20 80 a no local smoke ,v in = v dd ( @v dd =9v) input pull-down current i in 712 140 a no local smoke ,v in =17v( @v dd =12v) 11 6.5 0.6 v i o = 10ma 8, 9 6.5 1.0 v i o = 16ma low-level output voltage v ol 13 6.5 0.5 vi o = 5ma high-level output voltage v oh 8, 9 6.5 5.5 vi o = -16ma 12 v dd -0.1 v inactive , i o = -1 a strobe output voltage v st 4 9v dd -5.6 v dd -4.4 v active , i o = 100 a to 500 a line regulation v st( vdd) -60 db active , v dd = 6v to 12v 12 0.1 v inactive , i o =1 a , t a = +25 i red output voltage v ired 6 9 2.25 3.0 3.75 v active , i o = -6ma , t a = +25 line regulation v ired( vdd) -35 db active , v dd = 6v to 12v high-level output voltage i oh 79 -4.0 ma v dd = alarm , i/o active , v o = v dd -2v off leakage current high i oz 11 12 1.0 a v o = v dd off leakage current low i oz 11 12 -1.0 a v o = v ss low v dd alarm threshold v dd ( th ) 6.5 7.2 7.8 v common mode voltage v ic 1, 2, 3 v dd -4 v dd -2 v any alarm condition smoke comparator ref. volt. v ref int. v dd -3.92 v dd -3.08 v any alarm condition * limits over the operating temperature ra nge are based on characterization data. characteristics are prod uction tested at +25 . typical values are at +25 and are given for circuit design information only.
8/10 2006-01-25 photoelectric smoke detector with interconnect smoke detector M75010 ?A?w??? mosdesign semiconductor corp. ac electrical characteristics (ta=-25 ~ 75 ) characteristics sym. v dd min. typ. max. unit conditions oscillator period t osc 9 9.4 10.5 11.5 ms t led1 939 48 s no local or remote smoke t led2 9none s remote smoke only led pulse period t led3 9 0.45 0.50 0.55 s local smoke or test led pulse width t w (led) 99.5 11.5 ms t st1 99.6 11.9 s no local or remote smoke t st2 9 1.8 2.0 2.2 s after 1 or 3 valid samples t st3 9 0.8 1.0 1.1 s after 2 or 3 valid samples and during local alarm t st4 9 7.2 8.0 8.9 s remote alarm t st5 938.9 47.1 s chamber test or low supply test , no local alarm strobe pulse period t st6 9 300 336 370 ms pushbutton test , no alarm strobe pulse width t w (st) 99.5 11.5 ms t ired1 99.6 11.9 s no local or remote smoke t ired2 9 1.8 2.0 2.2 s after 1 or 3 valid samples t ired3 9 0.8 1.0 1.1 s after 2 or 3 valid samples and during local alarm t ired4 9 7.2 8.0 8.9 s remote alarm t ired5 938.9 47.1 s chamber test , no local alarm i red pulse period t ired6 9 300 336 370 ms pushbutton test , no alarm i red pulse width t w (ired) 994 116 s i red rise time t r ( ired ) 30 s 10% to 90% i red fall time t f (ired) 200 s 90% to 10% i/o to active delay t d (io) 9 0 s local alarm i/o charge dump duration t dump 9 0.9 1.0 1.1 s end of local alarm or test rising edge on i/o to alarm t r ( io ) 9 1.34 s no local alarm horn warning pulse period t horn 938.9 47.1 s low supply and degraded chamber sensitivity horn warning pulse width t w (horn) 99.5 11.5 ms low supply and degraded chamber sensitivity horn on time t on (horn) 9 216 280 ms local or remote alarm horn off time t off (horn) 9 80 83 ms local or remote alarm * limits over the operating temperature ra nge are based on characterization data. characteristics are prod uction tested at +25 . typical values are at +25 and are given for circuit design information only.
9/10 2006-01-25 photoelectric smoke detector with interconnect smoke detector M75010 ?A?w??? mosdesign semiconductor corp. electrical characteristics ( ? ) stand-alone 1. va l u e f o r r 11 r12 and c6 may differ depending on type of piezoelectric horn used. 2. c2 and r7 are used for coarse sensitivity adjustment. typical values are shown. 3. c4 should be 22 f if b1 is a carbon battery. c4 could be reduced to 1 f when an alkaline battery is used. c1 0.047 f r1 5.6k c2 4700pf r2 5k c3 100 f r3 8.2k c4 22 f r4 1k c5 1500pf r5 560 c6 1000pf r6 200k r7 4.7 ~22 r8 330 r9 7.5m r10 100k r11 200k r12 2m r13 220 r14 100k r15 47k M75010p 116 89 r1 vdd vdd r9 r11 r6 r2 r5 strobe detect r3 c2 9v c1 r10 r12 c4 c6 trip test c5 r7 c2 to/from units othe r c1 r13 r8 i/o ired horn1 oscr vss led oscc horn2 feedbac k c3 test to push r4 d1 r14 r15
10/10 2006-01-25 photoelectric smoke detector with interconnect smoke detector M75010 ?A?w??? mosdesign semiconductor corp. ( ) network 1. c2 and r7 are used for coarse sensitivity adjustment. typical values are shown. 2. c4 should be 22 f if b1 is a carbon battery. c4 could be reduced to 1 f when an alkaline battery is used. 3. feedback ( pin10) trip ( pin15 ) and test ( pin16 ) must connect to ground. * all specs and applications shown above subject to change without prior notice. ( ?H , ?? ) c1 0.047 f r1 5.6k c2 4700pf r2 5k c3 100 f r3 8.2k c4 22 f r4 1k c5 1500pf r5 560 r6 200k r7 4.7 ~22 r8 7.5m r9 100k r10 220 M75010p 116 89 r1 vdd vdd r 8 r6 r2 r5 strobe detect r3 c2 9v c1 r9 c4 trip test c5 r7 c2 to/from units othe r c1 r10 i/o ired horn1 oscr vss led oscc horn2 feedbac k c3 r4 d1
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