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6–7

Table 6–4. Infrared Receiver Component Functions (Normal Transmission Mode)

DEVICE

FUNCTION

TMS3637 configured as a logic normal (1-code) Q-state inverting receiver

Current-limiting resistor for IR transistor Q1

Base-bias resistor for Q1

Collector current-limiting resistor for Q2

Collector current-limiting resistor for Q3

Emitter current-limiter for Q3

Resistor on TIME that, in conjunction with C3, determines OUT pulse duration on U1.

Resistor on OSCR that, in conjunction with C4, determines internal oscillator frequency of U1.

Current-limiting resistor for LED indicator

AC-coupling capacitor that passes fluctuating voltage from phototransistor Q1

Power-supply bypass capacitor

Capacitor on TIME that, in conjunction with R6, determines OUT pulse duration on U1.

Capacitor on OSCC that, in conjunction with R7, determines the internal oscillator frequency of U1.

Capacitor that determines the gain of the internal analog receive amplifier on U1.

LED indicator that toggles on/off when valid code is received

100 k

Ω

OSCR

OSCC

TIME

GND

C4
47 pF

VCC

CEX

OUT

U2 (receiver)

R6
1 M

Ω

470 nF

330

Ω

VCC

OUT

R4
10 k

Ω

100 k

Ω

C2
47

330

Ω

R2
100 k

Ω

0.1

R5
2.7 k

Ω

Q3
2N2222

Q2
2N2222

Q1
NPN IR
Phototransistor

Figure 6–5. Infrared Receiver

Summary of Contents for TMS3637P

Page 1: ...i TMS3637 Remote Control Transmitter Receiver Data Manual SCTS037B JUNE 1997 ...

Page 2: ...IGNED INTENDED AUTHORIZED OR WARRANTED TO BE SUITABLE FOR USE IN LIFE SUPPORT APPLICATIONS DEVICES OR SYSTEMS OR OTHER CRITICAL APPLICATIONS Inclusion of TI products in such applications is understood to be fully at the risk of the customer Use of TI products in such applications requires the written approval of an appropriate TI officer Questions concerning potential risk applications should be d...

Page 3: ...4 1 Abort Retry 2 3 2 4 2 EEPROM Read Mode 2 3 2 4 3 EEPROM Write Mode 2 3 2 4 4 Data Input Setup and Hold Times 2 3 2 5 Switching Characteristics Over Recommended Ranges of Supply Voltages and Free Air Temperature 2 3 2 5 1 Normal Transmission Internal Clock 2 3 2 5 2 Modulated Transmission Internal Clock 2 3 3 Parameter Measurement Information 3 1 4 Typical Characteristics 4 1 5 Principles of Op...

Page 4: ...er Modes 5 12 5 12 1 Normal Mode CB 1 5 13 5 12 2 Modulated Mode CB 0 5 13 5 12 3 Analog Mode CF 0 5 13 5 12 4 Logic Mode CF 1 5 14 5 12 5 Noninverting Mode CI 0 or Inverting Mode CI 1 5 14 6 Application Information 6 1 6 1 General Applications 6 1 6 2 Direct Wired Connection of Transmitter and Receiver 6 1 6 2 1 Two Wire Direct Connection 6 1 6 2 2 Four Wire Direct Connection 6 3 6 3 Infrared Cou...

Page 5: ...h Voltage Programming Pulse 4 2 5 1 EEPROM Read Mode 5 2 5 2 EEPROM Write Mode 5 3 5 3 Amplifier Comparator Schematic 5 5 5 4 OUT Waveform in Normal Transmission 5 9 5 5 OUT Waveform in Modulated Mode 5 9 5 6 Transmitter Configurations 5 10 5 7 Receiver Configurations 5 13 6 1 Two Wire Direct Connection 6 3 6 2 Four Wire Direct Connection 6 4 6 3 Four Wire Direct Connection Key 6 5 6 4 Infrared Tr...

Page 6: ...e Receiver 5 12 6 1 Two Wire Direct Connection 6 2 6 2 Four Wire Direct Connection 6 4 6 3 Infrared Transmitter Component Functions Normal Transmission Mode 6 6 6 4 Infrared Receiver Component Functions Normal Transmission Mode 6 7 6 5 Infrared Receiver Component Functions Modulated Tranmission Mode 6 9 6 6 RF Transmitter Component Functions 6 10 6 7 TRF1400 RF Receiver and TCM3637 Decoder Parts L...

Page 7: ...cludes several internal features that normally require additional circuitry in a system design These include an amplifier comparator for detection and shaping of input signals as low as several millivolts typically used when an RF link is employed and an internal oscillator used to clock the transmitted or received security code The TMS3637 is characterized for operation from 25 C to 85 C 1 1 Feat...

Page 8: ...de and High Voltage Interface Power On Reset Oscillator GND 5 3 OUT TIME Shift Register EEPROM Memory 7 6 1 2 IN CEX OSCR OSCC Logic Circuit GND VCC 4 8 1 3 Terminal Assignments 1 2 3 4 8 7 6 5 OSCR OSCC TIME GND VCC IN CEX OUT D OR P PACKAGE TOP VIEW ...

Page 9: ...lator frequency In addition the internal oscillator triangular waveform can be seen at OSCC in this configuration When the device is in the data loading phase of the programming mode OSCC must be held at VCC 0 5 V After the device has been loaded with data in the programming mode the internal registers transfer the data to the EEPROM permanently by applying a high voltage programming pulse to OSCC...

Page 10: ...itter and if TIME is then forced low the device transmits one code or a code train TIME must be connected to an external pullup When the device is configured as a periodic transmitter connect an external resistor and capacitor between TIME and VCC to transmit code after each RC time constant has expired When the device is configured as a VTR TIME must be held high to receive codes The device produ...

Page 11: ...e with respect to GND 2 2 Recommended Operating Conditions MIN NOM MAX UNIT Supply voltage VCC 3 6 V High level input voltage VIH VCC 0 5 VCC V Low level input voltage VIL 0 0 5 V Operating free air temperature TA 25 85 C Receiver supply current analog ICC an 2 mA Receiver supply current digital ICC dig 200 µA Transmitter supply current standby ICC stdby 13 µA Transmitter supply current code trans...

Page 12: ...DITIONS MIN TYP MAX UNIT VI PP Peak to peak input voltage 3 mV VN PP External peak to peak noise voltage 1 mV VO Output voltage TIME VOL VOH V VI 3 mV 15 B Bandwidth VI 100 mVpeak to peak 500 kHz VI 200 mVpeak to peak 1000 AV Flatband gain CEX nF 900 fosc kHz 200 V V AV Flatband gain CEX not connected 1 V V 2 3 3 Internal Oscillator see Note 3 PARAMETER MIN TYP MAX UNIT fRX Receiver frequency 10 5...

Page 13: ...AX UNIT tsu4 Setup time data in before OSCR 1 µs th1 Hold time data in after OSCR 1 µs 2 5 Switching Characteristics Over Recommended Ranges of Supply Voltages and Free Air Temperature unless otherwise noted 2 5 1 Normal Transmission Internal Clock see Figure 3 6 PARAMETER MIN TYP MAX UNIT tw8 Pulse duration half oscillating period for OSCC sawtooth 5 1 2 x fosc 100 µs tw9 Pulse duration logic bit...

Page 14: ...2 4 ...

Page 15: ...formation tp1 tw1 IN VIH VIL VIH VIL tw2 tp0 OSCC Figure 3 1 Normal Transmission External Clock IN tw3 OSCC tsu1 Figure 3 2 VTR Generation OSCR clock in VCC tw5 tw4 5 V 4 Reset Pulses 5 V tsu2 5 5 V OSCC Figure 3 3 EEPROM Read Mode ...

Page 16: ...on Bits C01 C22 CA CI OUT previous data tsu3 High Voltage Programming Pulse Figure 3 4 EEPROM Write Mode OSCR clock IN data in th1 tsu4 Figure 3 5 Data In Setup and Hold Times tw8 tw8 tw9 tw10 OSCC IN VIH VIL VIH VIL Figure 3 6 Normal Transmission Internal Clock tc total tw11 tw12 IN tw H tc Figure 3 7 Modulated Transmission Internal Clock ...

Page 17: ...ly Voltage V 0 220 kΩ 300 8 0 Figure 4 1 Oscillator Resistance Versus Supply Voltage 10 100 1000 10000 100000 1000000 Rosc 100 kΩ Rosc 47 kΩ Rosc 22 kΩ 10 107 Cosc Oscillator Capacitance pF f osc Oscillator Frequency Hz 106 105 104 103 102 101 Figure 4 2 Oscillator Frequency Versus Oscillator Capacitance ...

Page 18: ...4 2 3 ms 5 5 V 15 V t Time ms Input Voltage at OSCC V 15 10 5 1 ms 5 10 15 16 13 14 11 12 1 2 3 4 6 7 8 9 ÁÁÁ ÁÁÁ V I 0 0 Figure 4 3 High Voltage Programming Pulse ...

Page 19: ...described in the following steps is used to read the current contents of the EEPROM memory This can verify that the correct 22 security codes and 9 configuration bits are stored in memory see Figure 5 1 1 Set VCC to 5 V 2 Apply VCC 0 5 V to OSCC Wait at least 50 ms to allow the device to assume the read mode tsu2 50 ms This voltage on OSCC forces the device into the read mode and the terminals are...

Page 20: ...CC 0 5 V to OSCC step 2 wait at least 50 ms to allow device to go into the program mode 4 Apply exactly four clock reset pulses to OSCR clock input These reset pulses are applied before clock input pulses for the 31 data bits that contain the security code and configuration bits The minimum duration of the clock reset pulses must be tw6 tw7 5 µs which equates to a clock frequency 100 kHz 5 Apply e...

Page 21: ...nfiguration Bits C01 C22 CA CI OUT previous data tsu3 High Voltage Programming Pulse Previous data refers to data that was previously programmed into the device If programmed for first time this contains a random test code from the factory Figure 5 2 EEPROM Write Mode 5 3 Internal Oscillator Operation for Transmit and Receive Modes Setting Frequency The TMS3637 has an internal oscillator that can ...

Page 22: ... the TMS3637 is configured as an analog receiver When the amplifier is not configured as an analog receiver it is disabled and bypassed to reduce power consumption in any of the three logic receiver modes A capacitor connected between CEX to GND determines the gain of the amplifier stage When no capacitor is connected from CEX to GND the amplifier assumes unity gain and the comparator still functi...

Page 23: ...r the amplifier test mode apply VCC 0 5 V to OSCC and apply three or more low level pulses to OSCR This can be done by simply brushing a wire connected from OSCR to GND The output of the amplifier stage is then connected internally to TIME where it can be sampled for evaluation purposes 5 8 Mode and Configuration Overview The TMS3637 device is designed to function in many modes and configurations ...

Page 24: ...acitor to GND internal 10100000X 1 Modulated Periodic clock or resistor to GND internal clock and output of the i t l Starts transmitting h l Serial output of currently d d N C N C Transmit data from 100000000 3 Code Train Normal Triggered GND internal clock internal clock triangular waveform when low stored data memory 110DE0001 3 Code Train Normal Periodic waveform 110DE0000 1 Code Train Modulat...

Page 25: ...configuration includes noninverting or inverting and number of codes train X don t care and can be held high or low I 1 inverting I 0 for noninverting The multitude of transmit and receive configurations are discussed in subsection 5 10 3 and Section 5 12 A reference for the quick correct programming of the device in the desired mode and configuration is discussed in Section 5 12 Table 5 4 lists t...

Page 26: ...us transmitter must be operated in either the normal CB 1 or modulated CB 0 modes 5 9 2 Triggered Transmitter CC 0 CI 1 When the chip is configured as a transmitter CA 1 CF CG CH 0 and EEPROM bits CC and CI low and high respectively the chip is programmed to work as a triggered transmitter The TMS3637 transmits a single code or a code train when TIME is forced low and then the device enters the st...

Page 27: ...dulated Mode CB 0 When the chip is configured as a continuous transmitter CA 1 CF CG CH 0 and CC 1 as a triggered transmitter CA 1 CF CG CH 0 and CC 0 CI 1 or as a periodic transmitter CA 1 CF CG CH 0 and CC 0 CI 0 and EEPROM bit CB clears to 0 the device is programmed to function as a modulated transmitter The oscillator frequency must be 120 kHz In the modulated mode a bit code 1 is represented ...

Page 28: ...titude of receiver configurations 48 possible configurations The configuration must match the transmitter when selecting the receiver configuration see Table 5 6 to determine compatible transmitter and receiver combinations The definition of which configuration bits to set for all the possible 48 receiver configurations is discussed in Section 5 12 In the receive mode the TMS3637 receives the tran...

Page 29: ...ected to TIME When the TMS3637 recognizes the received code as correct it produces a high pulse VTR pulse on OUT The VTR output pulse duration is equal to 48 times the pulse duration of the received data and is produced after a delay time equal to 152 2 fosc from the end of the received code If a capacitor is added in parallel to the pullup resistor on TIME the VTR pulse duration on the output ter...

Page 30: ...in Receiver CD CE TRAIN 1 0 2 codes 0 1 4 codes 1 1 8 codes 5 11 3 Q State Receiver CG 0 CH 0 CD CE When the TMS3637 is configured as a receiver CA CC 0 and EEPROM bits CG and CH are both cleared to 0 the device is configured as a Q state receiver Bits CB CF and CI must also be set to specify modulated or normal modes analog or logic for normal mode only and noninverting or inverting format of the...

Page 31: ... 5 12 2 Modulated Mode CB 0 The modulated receiver functions in a way that corresponds to a modulated transmitter The oscillator frequency of the receiver must be 480 kHz The signal used as an input must be demodulated to the carrier frequency of 40 kHz and then sent to IN 5 12 3 Analog Mode CF 0 In this configuration the received code is sent directly to IN where it is amplified and passed throug...

Page 32: ...taken to determine if a noninverting or inverting receiver should be used Transmitting from OUT on the transmitter is considered inverted Transmitting from IN on the transmitter is considered noninverted Using the logic mode on the receiver CF 1 does not invert the signal Using the analog mode on the receiver CF 0 does invert the signal Determine whether the signal path between the transmitter and...

Page 33: ...in receiver The oscillating frequency of the transmitter is approximately 5 7 kHz With VCC 5 V the transmitted code on OUT point A is a square waveform between 0 V internal connection to GND and 5 V At point B the maximum value is 5 V when OUT is open and the minimum value is 4 8 10K 10K 220 4 892 V when OUT is at 0 V The voltage swing is then 5 V 4 892 V 108 mV The voltage swing must not be much ...

Page 34: ...divider used to bias receiver output R6 Resistor that is part of RC low pass network on front end of U2 receiver R7 Resistor on TIME that along with C5 determines OUT pulse duration on U2 R8 Resistor on OSCR that in conjunction with C7 determines internal oscillator frequency on U2 R9 Current limiting resistor for LED indicator C1 Capacitor on OSCC that in conjunction with R2 determines internal o...

Page 35: ...esistor The frequency of the oscillator is approximately 26 kHz The receiver is configured as a logic normal 1 code Q state inverting receiver and the content of the EEPROM cells is CA CB CC CD CE CF CG CH CI 0 1 0 0 0 1 0 0 1 The receiver is used in the inverting mode The code is considered to be inverted when using OUT on the transmitter to transmit the code The signal path between the transmitt...

Page 36: ...llup resistor for transmitter OUT which is an open drain output R5 Current limiting resistor for D1 C1 Part of feedback circuit used to cause U3 to oscillate C2 Capacitor on TIME that in conjunction with R2 determines OUT pulse duration on U2 C3 Capacitor on OSCC that in conjunction with R3 determines internal oscillator frequency of U2 D1 LED for indication of received code OSCR OSCC TIME GND C1 ...

Page 37: ...pproximately 26 kHz The receiver is configured as a logic normal 1 code Q state inverting receiver and the content of the EEPROM cells is CA CB CC CD CE CF CG CH CI 0 1 0 0 0 1 0 0 1 The receiver is used in the inverting mode The code is considered to be inverted when using OUT on the transmitter to transmit the code The signal path between the transmitter and receiver does not invert the signal U...

Page 38: ...s for Q1 R5 Current limiting collector resistor for Q1 R6 Pullup resistor for TIME C1 Capacitor on OSCC that in conjunction with R1 determines the internal oscillator frequency of U1 C2 Power supply bypass capacitor D1 LED for visual indication of transmitted code D2 Infrared LED used to transmit code Q1 The pnp transistor that drives infrared LEDs S1 S1 is closed for transmission R1 100 kΩ OSCR O...

Page 39: ... Current limiting resistor for LED indicator C1 AC coupling capacitor that passes fluctuating voltage from phototransistor Q1 C2 Power supply bypass capacitor C3 Capacitor on TIME that in conjunction with R6 determines OUT pulse duration on U1 C4 Capacitor on OSCC that in conjunction with R7 determines the internal oscillator frequency of U1 C5 Capacitor that determines the gain of the internal an...

Page 40: ... Rosc and Cosc The receiver is cascaded with a TDA3048 or equivalent to process the received signal and demodulate it The receiver is configured as a modulated 1 code Q state inverting receiver and the content of the EEPROM cells is CA CB CC CD CE CF CG CH CI 0 0 0 0 0 0 0 0 1 The receiver is used in the inverting mode The code is considered to be inverted when using OUT on the transmitter to tran...

Page 41: ...miting resistor C1 Power supply filter capacitor C2 Capacitor on TIME that in conjunction with R2 determines OUT pulse duration on U2 C3 Capacitor on OSCC that in conjunction with R3 determines the internal oscillator frequency of U2 Q1 Infrared phototransistor for received code D2 Diode that is used to prevent back EMF in L2 from sourcing current to OUT L2 Coil of relay R1 RY1 Relay 12 V SPDT R2 ...

Page 42: ...h R1 determines the internal oscillator frequency of U1 C2 Capacitive part of LC tank circuit variable for frequency adjustment 2 pF 10 pF C3 Power supply bypass capacitor to present low impedance to RF on VCC L1 Inductive part of LC tank circuit strip line type L2 RF choke presents high impedance to RF between the tank and VCC Q1 The npn RF transistor turns on the LC circuit R1 22 kΩ OSCR OSCC TI...

Page 43: ...signal The signal path between the transmitter and receiver also inverts the signal The result is a signal that is noninverted at the internal logic controller of the receiver then C1 0 a noninverting receiver The receiver can be tuned from approximately 200 MHz 430 MHz using the trim capacitor C4 The antenna used is a metal wire that is 12 inches long Inductances L1 and L2 are in the range of 0 2...

Page 44: ...A1T RFIN1 AGND OFFSET AV DV SAW Filter RF Input AVCC C11 C12 C16 C15 C14 C13 R3 R4 R5 C18 C19 C20 R6 R7 R8 DOUT TRIG BBOUT C17 DVCC R1 R2 C3 C2 C8 L1 L4 C7 C4 C9 C5 L2 L3 C6 C10 C1 CC AV CC CC R9 22 kΩ OSCR OSCC TIME GND C23 1 nF VCC IN CEX OUT U2 Decoder TMS3637 R10 1 MΩ C24 470 nF VCC 8 7 6 5 1 2 3 4 C21 47 nF C22 100 nF F1 Figure 6 8 TRF1400 RF Receiver and TMS3637 Decoder Circuit ...

Page 45: ...ÁÁÁ ÁÁÁÁÁÁ Murata ÁÁÁÁÁÁÁÁ ÁÁÁÁÁÁÁÁ GRM40X7R473K050 ÁÁÁÁÁÁ C11 ÁÁÁÁÁÁ Capacitor ÁÁÁÁÁÁÁÁ 2200 pF ÁÁÁÁÁÁ Murata ÁÁÁÁÁÁÁÁ GRM40X7R222K050BD ÁÁÁÁÁÁ ÁÁÁÁÁÁ C12 ÁÁÁÁÁÁ ÁÁÁÁÁÁ Capacitor ÁÁÁÁÁÁÁÁ ÁÁÁÁÁÁÁÁ 2200 pF ÁÁÁÁÁÁ ÁÁÁÁÁÁ Murata ÁÁÁÁÁÁÁÁ ÁÁÁÁÁÁÁÁ GRM40X7R222K050BD ÁÁÁÁÁÁ ÁÁÁÁÁÁ C13 ÁÁÁÁÁÁ ÁÁÁÁÁÁ Capacitor ÁÁÁÁÁÁÁÁ ÁÁÁÁÁÁÁÁ 0 022 µF ÁÁÁÁÁÁ ÁÁÁÁÁÁ Murata ÁÁÁÁÁÁÁÁ ÁÁÁÁÁÁÁÁ GRM40X7R223K050BL ÁÁÁÁÁÁ ÁÁÁÁ...

Page 46: ...t register clock circuit that outputs exactly 35 bits serially four reset pulses 22 security bits and 9 configuration bits and 2 a transistor ramp generator that outputs the programming pulse required to store data in the EEPROM The following paragraphs detail the function of the circuit Before the momentary switch SW5 is pressed the shift registers U9 U13 shift load input is low so that they are ...

Page 47: ...d in this data manual see Figure 3 4 After the U5 time expires the voltage on OSCC again returns to 5 5 V approximately one diode drop above 5 V and the TMS3637 is programmed The U5 timer normally outputs one pulse when the circuit is powered up This is inherent of the timer device To prevent the timer from outputting this pulse and inadvertently programming the TMS3637 a power on reset RC combina...

Page 48: ...4 U4 B 4 3 B8 B7 4Q PR Q 0 47 µF C4 Ω 75 k R7 C3 TRIG RSET DSCH THRES CON OUT U8 TLC555I R3 Ω 2 2 k 5 V R4 Ω 7 5 k 0 01 µF C1 0 1 µF C2 Ω 10 k R5 5 V 1 µF C6 74HC21 U3 A Ω 3 9 k R6 SN74ALS04 U4 A Q 8 kHz QH QH QH A9 B9 Ω 10 k R12 R15 RN1 Ω 10 k RN2 SW3 UP DN UP DN UP DN C1 C22 Security Code 22 Bits CA CI Conf Code 9 Bits C 1 C 2 C 3 C 4 C 5 C 6 C 7 C 8 C 9 C 10 C 11 C 12 C 13 C 14 C 15 C 16 C 17 C...

Page 49: ... Ω R20 10 k Ω R19 10 k 17 15 13 11 8 6 4 2 18 16 14 12 9 7 5 3 0 0 1 0 0 0 1 1 1 19 5 V R8 D C B A SER IN LD CLK 74HC165 U12 INH H G F E QH VSS CR1 IN414B R9 R11 Ω 1 k OSCC U6 B 74HC393 U6 A 74HC393 1Q 2Q J1 IN Prog J1 OUT Read JP1 35 2A QH QH Ω 10 k R16 R18 Ω 10 k RN3 UP DN SW4 C C C D C E C F C G C H C I Unused Notch in lower left corner of dip switches Up is open 1 down is closed 0 All the chip...

Page 50: ...level C2 Ceramic Capacitor 0 1 µF C2 sets control voltage level on U8 C3 Electrolytic Capacitor 0 22 µF With R6 C3 prevents generation of program pulse during initial power up C4 Electrolytic Capacitor 0 47 µF With R7 C4 sets time constant for U5 CEXT terminal C5 Ceramic Capacitor 0 1 µF C5 couples high voltage programming pulse to OSCC C6 Electrolytic Capacitor 1 µF C6 is 5 V supply filter capaci...

Page 51: ... TMS3637P DIP packages a 16 pin ZIF can be used lower portion unused For TMS3637N surface mount packages use a clamshell with a latch cover and DIP footprint This can be purchased from EmMulation Technology 408 982 0660 part AS 0808 015 3 The edge connector that is compatible with the TMS3637 PCB is a Sullins part EZC10DRTH or the equivalent as shown in Table 6 9 Ground terminals A1 A6 and B1 are ...

Page 52: ...6 20 ...

Page 53: ...CONDUCTOR PRODUCTS MAY INVOLVE POTENTIAL RISKS OF DEATH PERSONAL INJURY OR SEVERE PROPERTY OR ENVIRONMENTAL DAMAGE CRITICAL APPLICATIONS TI SEMICONDUCTOR PRODUCTS ARE NOT DESIGNED AUTHORIZED OR WARRANTED TO BE SUITABLE FOR USE IN LIFE SUPPORT DEVICES OR SYSTEMS OR OTHER CRITICAL APPLICATIONS INCLUSION OF TI PRODUCTS IN SUCH APPLICATIONS IS UNDERSTOOD TO BE FULLY AT THE CUSTOMER S RISK In order to ...

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