Texas Instruments TMS3637 Installation and user guide

i
TMS3637
Remote Control Transmitter/Receiver
Data Manual
SCTS037B
JUNE 1997

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IMPORTANT NOTICE
Texas Instruments (TI) reserves the right to make changes to its products or to
discontinue any semiconductor product or service without notice, and advises its
customers to obtain the latest version of relevant information to verify, before placing
orders, that the information being relied on is current.
TI warrants performance of its semiconductor products and related software to the
specifications applicable at the time of sale in accordance with TI’s standard warranty.
TestingandotherqualitycontroltechniquesareutilizedtotheextentTIdeemsnecessary
to support this warranty. Specific testing of all parameters of each device is not
necessarily performed, except those mandated by government requirements.
Certain applications using semiconductor products may involve potential risks of death,
personal injury, or severe property or environmental damage (“Critical Applications”).
TI SEMICONDUCTOR PRODUCTS ARE NOT DESIGNED, 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
appropriateTIofficer.Questionsconcerningpotentialriskapplicationsshouldbedirected
to TI through a local SC sales office.
In order to minimize risks associated with the customer’s applications, adequate design
and operating safeguards should be provided by the customer to minimize inherent or
procedural hazards.
TI assumes no liability for applications assistance, customer product design, software
performance, or infringement of patents or services described herein. Nor does TI
warrant or represent that any license, either express or implied, is granted under any
patent right, copyright, mask work right, or other intellectual property right of TI covering
or relating to any combination, machine, or process in which such semiconductor
products or services might be or are used.
Copyright 1997, Texas Instruments Incorporated

iii
Contents
Title Page
1 Introduction 1–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.1 Features 1–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.2 Functional Block Diagram 1–2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.3 Terminal Assignments 1–2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.4 Terminal Functions 1–3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2 Specifications 2–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.1 Absolute Maximum Ratings Over Operating Free-Air Temperature Range 2–1. . . .
2.2 Recommended Operating Conditions 2–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.3 Electrical Characteristics Over Recommended Ranges of Supply Voltage
and Operating Free-Air Temperature 2–2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.3.1 Signal Interface 2–2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.3.2 Amplifier 2–2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.3.3 Internal Oscillator 2–2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.3.4 Power-On Reset 2–2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.3.5 Write/Erase Endurance 2–2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.4 Timing Requirements Over Recommended Ranges of Supply Voltages
and Free-Air Temperature 2–3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.4.1 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 Operation 5–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.1 Power-On Reset 5–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.2 EEPROM Memory (31 Bits) 5–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.2.1 Program Read Mode 5–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.2.2 Program Write Mode 5–2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.3 Internal Oscillator Operation for Transmit and Receive Modes Setting
Frequency 5–3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.4 Internal Oscillator Operation for Transmit and Receive Modes Sampling
Frequency 5–4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.5 External Oscillator Operation for Transmit and Receive Modes 5–4. . . . . . . . . . . . . . .
5.6 Internal Amplifier/Comparator, Description and Gain Setting 5–4. . . . . . . . . . . . . . . . .

iv
5.7 Internal Amplifier/Comparator Test Mode 5–5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.8 Mode and Configuration Overview 5–5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.9 Transmitter Configurations 5–8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.9.1 Continuous Transmitter (CC = 1) 5–8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.9.2 Triggered Transmitter (CC = 0, CI = 1) 5–8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.9.3 Periodic Transmitter (CC = 0, CI = 0) 5–8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.10 Transmitter Modes 5–8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.10.1 Normal Mode (CB = 1) 5–9. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.10.2 Modulated Mode (CB = 0) 5–9. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.10.3 Code-Train Mode (CD, CE) 5–9. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.11 Receiver Configurations 5–10. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.11.1 Valid Transmission Receiver (CG = 1, CH = 0) 5–11. . . . . . . . . . . . . . . . . . . .
5.11.2 Train Receiver (CG = 1, CH = 1, CD, CE) 5–11. . . . . . . . . . . . . . . . . . . . . . . .
5.11.3 Q-State Receiver (CG = 0, CH = 0, CD, CE) 5–12. . . . . . . . . . . . . . . . . . . . . .
5.12 Receiver 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 Coupling of Transmitter/Receiver –Normal Transmission Mode 6–5. . . . . .
6.4 Infrared Coupling of Transmitter/Receiver –Modulated Transmission Mode 6–8. . .
6.5 Radio Frequency (RF) Coupling of Transmitter and Receiver 6–10. . . . . . . . . . . . . . .
6.6 RF Receiver and Decoder 6–13. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.7 Programming Station 6–14. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.8 TMS3637 Programming Station Parts Lists 6–18. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.9 TMS3637 Edge-Connector Pinout 6–19. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

v
List of Figures
Figure Title Page
3–1 Normal Transmission –External Clock 3–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3–2 VTR Generation 3–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3–3 EEPROM Read Mode 3–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3–4 EEPROM Write Mode 3–2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3–5 Data In Setup and Hold Times 3–2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3–6 Normal Transmission –Internal Clock 3–2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3–7 Modulated Transmission –Internal Clock 3–2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4–1 Oscillator Resistance Versus Supply Voltage 4–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4–2 Oscillator Frequency Versus Oscillator Capacitance 4–1. . . . . . . . . . . . . . . . . . . . . . . . .
4–3 High-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 Transmitter 6–6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6–5 Infrared Receiver 6–7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6–6 Infrared Modulated Receiver 6–9. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6–7 Radio Frequency Transmitter 6–10. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6–8 TRF1400 RF Receiver and TMS3637 Decoder Circuit 6–12. . . . . . . . . . . . . . . . . . . . . .
6–9 Programming Station 6–16. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

vi
List of Tables
Table Title Page
5–1 Mode and Test Configuration 5–5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5–2 Transmitter Modes 5–6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5–3 Receiver Modes 5–7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5–4 Amplifier Test, Program, and Read Modes 5–7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5–5 Code-Train Modes 5–10. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5–6 Transmitter/Receiver Compatibility 5–11. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5–7 Bits CD and CE in Train Receiver 5–12. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5–8 Bits CD and CE in Q-State 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 List
(for 300 MHz operation) 6–13. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6–8 TMS3637 Programming Station Part List 6–18. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6–9 Edge Connector Pinout 6–19. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1–1
1 Introduction
The TMS3637 is a versatile 3-V to 6-V remote control transmitter/receiver in a small package that requires
no external dual-in-line package (DIP) switches on the system circuit board. The device can be easily set
for one of many transmit/receive configurations using configuration codes along with the desired security
code, both of which are user programmable. When used as a transmitter, the device encodes the stored
security code, transmits it to the remote receiver using any transmission media such as direct wiring,
infrared, or radio frequency. When configured as a receiver, the TMS3637 continuously monitors and
decodes the transmitted security code (at speeds that can exceed 90 kHz) and activates the output of the
device when a match with its internally stored code has been found. All programmed data is stored in
nonvolatileEEPROMmemory.Withmorethanfourmillioncodesalterableonly withaprogrammingstation,
the TMS3637 is well suited for remote control system designs that require high security and accuracy.
Schematics of the programming station and other suggested circuits are included in this data manual.
Inadditiontothedeviceconfigurationandsecuritycodecapabilities,theTMS3637includesseveralinternal
featuresthatnormallyrequireadditionalcircuitryinasystemdesign.Theseincludeanamplifier/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 Features
•Data Encoder (Transmitter) or Data Decoder (Receiver) for Use in Remote Control Applications
•High Security
–4,194,304 Unique Codes Available
–Codes Stored in Nonvolatile Memory (EEPROM)
–Codes Alterable Only With a Programming Station That Ensures No Security Code
Duplications
•Versatile
–48 Possible Configurations as a Receiver
–18 Possible Configurations as a Transmitter
–Single, Multiple, or Continuous Cycling Transmission
•Easy Circuit Interface With Various Transmission Media
–Direct Wired
–Infrared
–Radio Frequency
•Minimal Board Space Required: 8-Pin (D or P) Package and No DIP Switches
•Internal On-Chip Oscillator Included, No External Clock Required
•CMOS 2-µm Process Used for Very Low-Power Consumption and 3-V to 6-V Supply Voltage
•Well Suited for All Applications Requiring Remote-Control Operation
–Garage Door Openers
–Security Systems for Auto and Home
–Electronic Keys
–Consumer Electronics
–Cable Decoder Boxes
–Industrial Controls Requiring Precise Activation of Equipment
–Electronic Serial Number (ESN) Device Identification

1–2
1.2 Functional Block Diagram
Amplifier
Test Mode
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
48
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)

1–3
1.4 Terminal Functions
TERMINAL
I/O
DESCRIPTION
NAME NO.
I/O
DESCRIPTION
CEX 6 I Capacitor external. CEX is used for gain control of the internal analog amplifier. An external
capacitor connected from CEX to GND determines the gain of the amplifier. If the internal
amplifier is set for unity gain or the device is not used as a receiver, CEX is left unconnected.
GND 4 Ground
IN 7 I/O Depending on the device configuration, IN provides inverted OUT data, is used as a receiver
input, or is used to enter data during programming.
–When the device is configured as a transmitter, IN provides the complement of the OUT
data stream and is considered to be noninverted. IN provides its own internal pullup, so
no external pullup is required when IN is used to transmit the data. It is cleared to 0 in
standby.
–When the device is configured as a receiver, IN is used to receive the code.
–When the device is in the program mode, IN is used to enter serial data into the device
shift registers that load into the EEPROM memory.
OSCC 2 I/O Oscillatorcapacitor.Dependingontheconfiguration,OSCCisusedforexternaltransmit/receive
clock input, control of the internal oscillator, to place the device into program mode, input for a
high-voltage EEPROM programming pulse, or the internal analog amplifier in the test mode.
–When the device is used as a transmitter or receiver using an external clock, the external
clock is connected directly to OSCC. (OSCR must be held low to use an external clock.)
–When the device is used as a transmitter or receiver and the internal oscillator is used,
a capacitor from OSCC to GND and a resistor from OSCR to GND determines the
free-running internal oscillator 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.
–When OSCC is held at VCC + 0.5 V and three or more low pulses are applied to OSCR,
the device is in the test mode and the output of the internal analog amplifier can be
measured at TIME.
OSCR 1 I Oscillator resistor. Depending on the configuration, OSCR is used as an external program/
read clock input or to control the internal clock frequency.
–When the device is in the program/read mode, OSCR is connected to an external clock.
–When the device is in the transmit or receive mode, a resistor connected from OSCR to
GND(alongwithacapacitorfromOSCCtoGND)determinesthefrequencyoftheinternal
clock.
OUT 5 O OUTisan open-drainoutput.Forthat reason,itisnecessary toconnectapullup resistor toOUT.
Dependingon the configuration,OUTprovides transmit data, acts as the outputforthereceiver,
or provides the serial output of the stored data in memory during the program and read modes.
–When the device is configured as a transmitter, the transmitted data is seen at OUT and
is in a 3-state output mode during standby (OUT is floating). While transmitting, the data
from OUT is considered inverted.
–When the device is configured as a valid transmission receiver (VTR) receiver, OUT
provides a VTR pulse and goes low in the standby mode.
–Whenthe deviceisconfiguredasa Q-statereceiver, OUT toggleshighandlow eachtime
a valid code is received.
–During the program mode, OUT provides the current data from the EEPROM memory
when the new data is clocked into the device.

1–4
1.4 Terminal Functions (Continued)
TERMINAL
I/O
DESCRIPTION
NAME NO.
I/O
DESCRIPTION
TIME 3 I/O Dependingontheconfiguration,TIME isusedformeasuring theinternalanalog-amplifieroutput
inthedevice testmode,puttingthedevice intothetransmitmode, or controllinganinternalclock
oscillator for various transmitter and receiver configurations.
–When OSCC is held at VCC + 0.5 V and three or more low pulses are applied to OSCR,
the device is in the test mode and the output of the internal analog amplifier can be
measured at TIME.
–Whenthedeviceisconfiguredasacontinuoustransmitter,aninternalpullupisconnected
to TIME. If TIME is then forced low, the device transmits codes for the duration that TIME
is held low. (TIME must be connected to an external pullup.)
–When the device is configured as a triggered transmitter 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 produces a VTR pulse on OUT after confirmation of a correct received code.
ConnectingaparallelresistorandcapacitorbetweenTIMEandVCClengthenstheoutput
pulse (VTR) duration.
–Configuredasatrainreceiver,connectanexternalparallelresistorandcapacitorbetween
TIMEandVCC, which are used tosetthelengthoftime the device is lookingfortwo,four,
or eight correct received codes to output a valid VTR pulse on OUT.
–ConfiguredasaQ-statereceiver,TIMEhasthesamefunctionastheVTRreceiverabove,
except the detection of the correct code causes OUT to toggle between the low and high
states.
VCC 85-V supply voltage