HT-12E 12-Bit Encoder IC DIP-18
The HT12E is a CMOS 12-bit encoder in an 18-pin DIP (also available in 20-pin SOP) designed for simple, reliable remote-control data encoding. It converts the logic states of eight fixed address pins plus four address/data pins into a serial output stream when its TE (transmit enable) input is activated. The device includes an on-chip oscillator (RC type) so it can generate timing internally with only a single resistor, simplifying board layout and reducing components.
When TE is asserted low the HT12E begins a repeated transmission cycle that serializes the programmed address and data bits with a leading sync/pilot pattern; this cycle continues while TE is held low and finishes the last word when TE returns high. The chip supports latch or momentary transmission formats via the L/M pin, allowing it to work with different decoder formats and application requirements without external logic.
Built for remote controls, alarm panels and simple RF/IR links, the HT12E emphasizes low standby current and high noise immunity so battery-powered systems can remain idle for long intervals. Its wide supply range (2.4 V to 12 V), low external part count, and compatibility with Holtek’s 2^12 decoder family make it a compact, robust choice for short-range encoded transmissions in consumer and security electronics.
Features:
- Operates over a wide VDD range: 2.4 V to 12 V.
- Low standby current (typ. 0.1 µA at VDD = 5 V).
- Built-in RC oscillator needs only one resistor for timing.
- TE (transmission enable) controlled transmission; L/M selects latch or momentary mode.
- High noise immunity and low external component count.
- Positive-polarity data code and compatible with Holtek 2^12 decoder series.
Specifications:
| Parameter | Value / Condition |
|---|---|
| Part / Function: | HT12E — 12-bit encoder (8 address + 4 address/data). |
| Recommended VDD (operating): | 2.4 V to 12 V. |
| Absolute maximum VDD: | −0.3 V to +13 V. |
| Standby current (ISTB): | Typ 0.1 µA (VDD = 3–5 V, oscillator stopped). Max values in datasheet. |
| Operating current (IDD): | Typ 40 µA (VDD = 3 V, fOSC ≈ 3 kHz); typ 150 µA at 12 V (see datasheet). |
| Output drive (IDOUT): | Source ≈ 1–1.6 mA; Sink ≈ 1–1.6 mA (VOH = 0.9VDD / VOL = 0.1VDD at 5 V). |
| Oscillator frequency (fOSC): | ≈ 3 kHz with ROSC = 1.1 MΩ (typical example). |
| Input thresholds (VIH / VIL): | VIH ≈ 0.8·VDD to VDD; VIL ≈ 0 to 0.2·VDD. |
| TE pull-high resistance (RTE): | Typ 1.5 – 3 MΩ (5 V, VTE = 0 V measured). |
| Operating temperature (TA): | −20 °C to +75 °C (per datasheet). |
Pinout Diagram:
Pin Configuration:
| Pin Number | Pin Name | Description |
| 1 to 8 | A0,A1,A2,A3,A4,A5,A6 & A7 | These are the 8-bit address bits, which is used to protect your data. We should set the bits in same pattern on Encoder and Decoder IC to pair them. |
| 9 | Ground/Vss | Connected to the Ground of circuit |
| 10 to 13 | AD0, AD1, AD2 & AD3 | These four pins are used to send data, the data encoded here will be decoded on HT12D IC sharing the same address bits |
| 14 | Transmission Enable(TE) | This pin has to be connected to Ground (0V) to enable the Transmission. |
| 15 and 16 | Oscillator pins 1 & 2 | The IC has a built in oscillator. This oscillator can be used by connecting these two pins through a 1M Resistor |
| 17 | Output | The Encoded 12 bit output data can be obtained from this pin |
| 18 | Vcc/Vdd | This pin powers the IC, typically +5V is used. Can range from 2.4V to 12V |
Applications:
- Burglar alarm systems.
- Smoke and fire alarm systems.
- Garage door controllers.
- Car door / car alarm controllers.
- Security systems.
- Cordless telephones and other remote control systems.
Package Contents:
- 1x HT-12E 12-Bit Encoder IC DIP-18
Reviews
There are no reviews yet.