M708AB1

M708 STMICROELECTRONICS | Alldatasheet

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7 7) SGS-THOMSON M708 MICROELECTRONICS M708A PCM REMOTE CONTROL TRANSMITTER ADVANCED DATA = 30 CHANNELS/4 ADDRESSES When the M708 works in conjunction with = SELECTABLE FLASH/CARRIER TRANS- — M490/M491 single chip Station Memory and R.C. MISSION MODE receiver the oscillator frequency can be in the range » END OF TRANSMISSION CODE 445 to 510 kHz and no synchronization is required = VERY LOW POWER DISSIPATION DURING with the receiver clock. Tego) Oo oe wewior ned) 0.15 % (flash The M708 is produced with CMOS Si-gate technol- 0.7 % lable | in-line plasti

0 SINGLE COM SAGT MATRIX KEYBOARD oay and, is available in a 20 pin dual in-line plastic

s INTEGRATED ANTIBOUNCE AND INTER- LOCK = WIDE SUPPLY RANGE (M708 4.5 to 10.5 V)(M708A 3 to 10.5 V) = WIDE REFERENCE FREQUENCY RANGE (445 to 510 kHz ceramic resonator) = 20 PIN PLASTIC PACKAGE _ a TO BE USED IN CONJUNCTION WITH M490/M491 SINGLE CHIP STATION MEMORY AND R.C. RECEIVER (flash mode) OR WITH | MICROPROCESSOR CONTROLLED SYSTEM (carrier mode)

DESCRIPTION

This IC has been developed for remote control in consumer applications. It uses a highly reliable transmission code which has the capacity of 1024 channels. Each transmitted word is structured into 4 bits which constitute the address and 6 bits which constitute the command. However only 2 addresses and 30 commands are available in this IC. An addi- tional command (000000) is used to transmit the “end of transmission code” when the key is re- leased. Additional bits are transmitted for synchronization of transmitter and receiver clocks and for security DIP20 checks. The address organization provides simulta- neous applications without interference among each system. The receiver accepts the decoded command only if ORDER CODES: M708 B1 the transmitted address matches the address se- M70BA B1 lected at the receiver. Four addresses are available for this purpose. The reference oscillator is control- | led by a cheap ceramic resonator. January 1989 19 This ahareed efor ona ew proc now m Gevepmen oF undega alaton Doles are BADREW Change witout rabee sa7

PIN CONNECTIONS, ™ (: 2of} Yoo osc.in [Jz asf) our ¥ y oo Ys oscm oscour test osc.ourf}> ref} Yss 4 « wi x — sooness |

6 Is wef oz z our

€ (ls rsfJresr | ™*Nobe" wcece Lunoea « uf) o AA Lo PoaeeS ry ls afl oP ssf TTT fa et PT The] 1 ig nfo ao a 2 59586 | » fo wf} Tar Note : The test pin must be connected 10 Ves ABSOLUTE MAXIMUM RATINGS Input Voltage = 03 to Voo + 0.3 | lol [1 Output Current (t < 60 us) [io ma Operating Temperature 0 to 70 Total Package Power Dissipation [200 | mw | Storage Temperature = 55 to 125 Stresses above those listed under “Absolute Maximum Ratings" may cause permanent damage to the device. This is a stress rating only and functional operation of the device at these or any other conditions above those indicated in the operational sections of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability RECOMMENDED OPERATING CONDITIONS Symbol [Parameter vate [oi Voo | Supply Voltage : M708 45 to 105 Vv M708 3 to 105 v input Voliage | oto Voo | [Tol [18 Out Goer (t= 50 na [max 25 | | | frer__| Reference Frequency 445 to 510 | [te | Serial Resistance of a Closed Key Contact | max.26 | Ka | | tp» __| Parallel Resistance of Open Key Contact, | min22 | Ma | [_R. __| Serial Resistance of the Ceramic Resonator | max.20 [| 2 | go ey scs-tHomson SY/ imcromscrnoncs 188

ENABLE —— os¢.1n KEYBOARD LOGIC OSCILLATOR i] —-osc.our ADDRESS DIVIDERS. TRANSMISSION CODE LATCH AND | CLOCK GENERATOR END OF OUTPUT, TRANSMISSION SEQUENCE LOGIC TRANSMISSION || Loci TRANS. MODE TEST 5 -$560 | SY iaicrosscinemice 189

STATIC ELECTRICAL CHARACTERISTICS (over recommended operating conditions) Typical values are at 9V and Tamy = 25°C Parameter Test Conditions [|__—_Yalue_] Supply Vollage Voo=9v{ Stand-oy | [5 | 15 [ua | IR Output | Operating Open (one key 7 closed) H State [Voo=9V Vonwev |-15[-25] | IR Output Cura [Woo 45 von «380-03 ]-o5[ |" {Sate [Voo=8v Vo-tv [is [-25[ | | Vin | Input Threshold High | Selection Inputs | Voo=9V | S| || v Awe [vosssv | TI Vit | Input Threshold Low | Selection inputs| Voo=9V | 8 | | | KtoQ v [Voo=asv fas | | Te Input Low Current Pul-up Inputs | Voo = 9 V HA AtoH Vu = 45 V Input High Current Pulldown Von =9V HA Inputs Vin = 45 V Ktoa a Input High Current Address Voo =9V 150 | pA Selection Vu, = 8.25 V Inputs (oscillator running) I Input Leakage Current | Trans, Mode Voo =9V HA Test Pin Vin =0 10 9 V | Output Current Voo =9V BA Osc. In. = Vss SY imcromzcracmcs, gan

Command] ___——nput Code | Command its | wofa ce G Hit MN Oo P alc1 c2 ca ca cs cel [0 _| END OF TRANSMISSION oo 0 0 0 0 1 x x 1 0 oO oO oO oO 2 x x 1 41 0 0 0 0 3 x x 0 0 1 0 0 oO 4 x x 1 i) 1 co) oO o 5 x x i) 1 1 0 oO co) 6 x x}|1 1 1 0 0 0 7 x x + 0 0 0 1 0 8 x x 1 1 o oO 1 oO 9 x x i) i) 1 oO 1 o 10 x x 1 0 1 0 4 0 W x x Oo 1 1 oO 1 oO 12 x x} 1 4 41 0 4 0 13, x x 1 i) i) oO oO 1 14 x x 1 1 o oO oO 1 15 x x o 0 1 0 0 14 16 x x 1 0 1 0 0 14 7 x x oO 1 1 oO oO 1 18 x x} 1 1 1 0 0 1 19 x x + 0 0 0 1 4 20 x x 1 1 0 0 4 14 ral x x i) 0 1 co) 1 1 22 x x 1 0 4 O 4 4 : 23 x x o 1 1 0 4 «4 24 x x 1 1 1 ) 1 1 25 x x 1 i) o 1 1 1 26 x x 1 1 Oo 1 1 1 27 x x oO oO 1 1 1 1 28 x x 1 00 4 4 4004 29 x x oO 1 1 1 1 1 30 x x}r 4 4 1 4 4 DESCRIPTION The different code introduced for the even and odd The signals are transmitted with infrared light using "1S" improves the capability to recognize false a Pulse Code Modulation. Each word consists of 12 codes atthe receiver end, eee encore bits. The binary information of a bitis determined by "Or ™ 4 the time interval between two pulses. If "T" is the _'S easily detected. A Parity bit is also added in order time base, the bits are coded as follows : to further increase the reliability of the transmission. This bit is "1" ifthe number of transmitted "1" is even Odd bits (1, 3, etc) while itis “0” if the number of transmitted "1" is odd. i ) v ar In addition, every word contains a preliminary pulse, O=T won fonts astart pulse anda stop pulse. The spacing between 1=2T the preliminary and the start pulse is 4T. This is fol- Sos36! lowed after 1T by 11 data pulses (one parity bit), and | Evenbits (2, 4, etc.) 1 aT terminated after a 4T interval by a stop pulse. Con- | o=T _ i ‘sequently, a word in which the binary digit 0 occurs ° ‘ ! ten times has a total duration of 217. A word con- | 1=3T s-sss2 taining ten "1s" has a duration of 36T. ey SeS-tHoMson | SYM iwcrosicraowcs 191

Example : aT TYyT 31 at 3T T 3T TUT; 2tytyy 4T i 1 a 1 i 1 ojo 1 0 —_— t { ADDRESS: COMMAND ! { PRELIM. START BITS BITS PARITY STOP. PULSE PULSE BIT PULSE 5-542 SYNCHRONIZATION BETWEEN TRANSMIT- the transmitter. The contact must be continuously TER AND RECEIVER closed for a minimum of 25 ms. one transriter ca ronconaen Nawal eles “in Double and multiple contact operations are not ac- - ' cepted. The command information is repeatedly able for correct operation of the system should be transmitted at intervals of 102 ms (fret = 500 KHz) as comprised between 445 and 510 kHz, usingacheap jong as the push button remains operated. When ceramic resonator. the contact is interrupted the circuit transmits, after Synchronization between the transmitter and the re- a pause of 18 ms, the "end of transmission code" ceiver, necessary to obtain the above described ang returns to stand-by mode. If the contact is inter- wide range of frequency tolerance is achieved by rupted while a commands being transmitted the cir- measuring in the receiver the interval between the cuit carries on with the transmission to the end. After start pulse andthe first data pulse, storing this value Soe of about 18 ms transmits the ord of tran. and using it as time base T. riesion code. KEYBOARD/CODE REPETITION No command is accepted until the “end of trans- One column, input (pins IMNOPGQ) has to be con- mission code" is over. nected to one row (pins ACEGH) input to activate COMMAND COMMAND END OF TRANSMISSION TRANSMISSION TRANSMISSION key FLASH CARRIER KEY cope a MODE MODE RELEASED } | 18ms, ANTIGOUNCE— REPENITION TIME (25ms) (02ms) 9-9553 so ey scs-tomson SY/ tacromsctaomes 192

TRANSMISSION MODE (pin T) ance frequency of 500 kHz the output signal has The M708 can operate in Flash (pinT=Voo) orCar- _‘these formats respectively : fier (pin T = Vss) transmission modes. Using a refer- Flash Mode > 10ps Transmission time min. = 2.1 ms T 2100 ps max. = 3.6 ms duty cycle = 0.15 % $-5555 Cartier Mode 26ps, bps. f = 38.43 KHz Transmission time { | min, = 32.76 ms 42.02 ps max = 56.16 ms duty cycle = 0.7 % TL36ms . gossse ADDRESS (pins X, Z) The address information is coded and transmitted as follows. ADORESS BITS COMMAND BITS eee _eE a a a a a A AND START PULSE BIT PULSE [-#—> Address i CO oO 0 oO oO L L 1 0 0 i) H L 0 0 0 1 L H

1 Co) 0 1 H H

The Address inputs have internal pull-downs which are disabled during stand-by. Single address selection Multiple address selection . x Zz x Zz Yoo V ADDRESS 2 DD ADDRESS 2 ADORESS10 S- $568 S-S567/1 ‘Note : Unused inputs can be lef open or connected fo Ves TYPICAL APPLICATIONS FLASH MODE 33 1 +0 oa ov —_ OL Aonarss 2xL0271 Yoo! twooe ~ | our <p e200 60237 220 pF | | SS a imcrad [}°2° | = 455 to SIOKHz 100pF WOpF INFRARED DIODE PEAK CURRENT = 1.8 A | TOTAL AVERAGE CONSUMPTION = 6.5 mA

89 L577 SSS:THOMSON ____-

| =) | SY Micaossctaomes 194

~ ADDRESS > o> y 2xL0271 00} ~ cs J TKN. 60237 220 pF KEYBOARD K__ | M708/A MODE 0.56 2x1N4148) [| a TEST 455 to S1OKHe 100pF W0pF INFRARED DIODE PEAK CURRENT = 1.25 A TOTAL AVERAGE CONSUMPTION = 13 mA | SY/ iucromscrmonscs 195