HT12D/HT12F 12 2 Series of Decoders Features Operating voltage: 2.4V~12V Built-in oscillator needs only 5% resistor Low power and high noise immunity CMOS Valid transmission indicator technology Easy interface with an RF or an infrared transmission Low standby current medium Capable of decoding 12 bits of information Minimal external components 12 Binary address setting Pair with Holtek s2 series of encoders Received codes are checked 3 times 18-pin DIP, 20-pin SOP package Address/Data number combination HT12D: 8 address bits and 4 data bits HT12F: 12 address bits only Applications Burglar alarm system Car alarm system Smoke and fire alarm system Security system Garage door controllers Cordless telephones Car door controllers Other remote control systems General Description 12 The 2 decoders are a series of CMOS LSIs for remote ously with their local addresses. If no error or un- control system applications. They are paired with matched codes are found, the input data codes are 12 decoded and then transferred to the output pins. The VT Holtek s2 series of encoders (refer to the encoder/de- pin also goes high to indicate a valid transmission. coder cross reference table). For proper operation, a 12 pair of encoder/decoder with the same number of ad- The 2 series of decoders are capable of decoding dresses and data format should be chosen. informations that consist of N bits of address and 12 N The decoders receive serial addresses and data from a bits of data. Of this series, the HT12D is arranged to pro- 12 programmed 2 series of encoders that are transmitted vide 8 address bits and 4 data bits, and HT12F is used to by a carrier using an RF or an IR transmission medium. decode 12 bits of address information. They compare the serial input data three times continu- Selection Table Function Data Address VT Oscillator Trigger Package No. Part No. No. Type HT12D 8 4 L RC oscillator DIN active Hi 18DIP, 20SOP HT12F 12 0 RC oscillator 18DIP, 20SOP DIN active Hi Notes: Data type: L stands for latch type data output. VT can be used as a momentary data output. Rev. 1.10 1 November 18, 2002HT12D/HT12F Block Diagram Note: The address/data pins are available in various combinations (see the address/data table). Pin Assignment % % % , % + % , % + * * , , & & & ) & ) * * & ( & ) & ( & ) ( ( ( ( ( ( ) ) ) & ) & ( ( ( ( * * * ) * ) % ) , & % % ) , & % * , * * , * + + + + + + + % , + % , % , % , Pin Description Internal Pin Name I/O Description Connection Input pins for address A0~A11 setting A0~A11 (HT12F) These pins can be externally set to VSS or left open. NMOS I Transmission Gate Input pins for address A0~A7 setting A0~A7 (HT12D) These pins can be externally set to VSS or left open. D8~D11 (HT12D) O CMOS OUT Output data pins, power-on state is low. DIN I CMOS IN Serial data input pin VT O CMOS OUT Valid transmission, active high OSC1 I Oscillator Oscillator input pin OSC2 O Oscillator Oscillator output pin VSS Negative power supply, ground VDD Positive power supply Rev. 1.10 2 November 18, 2002