The Hard Truth: No Official Library Exists Proteus (by Labcenter Electronics) does not include native simulation models for the HT12E (Encoder) and HT12D (Decoder) in its standard library. You will not find them by searching the "Pick Devices" window. Therefore, you have three options:
Download a 3rd Party Library (Risk of bugs, but common). Create a Sub-circuit Model (Most reliable for simulation). Use an Alternative IC (For simulation only).
Option 1: Download 3rd Party Library Files (Fastest) Several electronics forums host user-created .IDX and .LIB files for these ICs. Where to Look (Safe Sources) | Source | Typical File Name | Notes | | :--- | :--- | :--- | | GitHub | HT12E_HT12D_Proteus.zip | Search "ht12e proteus library". Safer than random sites. | | The Engineering Projects | Proteus_HT12E_HT12D.rar | Requires registration, but reliable. | | ElectroSome | HT12E_HT12D_Library.zip | Direct download often available. | Installation Steps (Proteus 8/9)
Download the .LIB and .IDX files (or .HEX if provided). Locate your Proteus Library folder (Default paths): Ht12e And Ht12d Proteus Library File Download
Windows 64-bit: C:\Program Files (x86)\Labcenter Electronics\Proteus 8 Professional\DATA\LIBRARY Or: C:\Users\YourUserName\Documents\Proteus 8 Professional\LIBRARY
Copy the downloaded .LIB and .IDX files into that folder. Restart Proteus . Search for HT12E or HT12D in the "Pick Devices" (P) window.
⚠️ Warning : 3rd party models often simulate only the digital encoding/decoding but not the oscillator (external resistor) or precise timing. They are fine for logic verification but not for real-world timing. The Hard Truth: No Official Library Exists Proteus
Option 2: Build a Sub-circuit Model (Most Professional) If you cannot find a working library, create a simulation substitute using Proteus primitives. This is what experienced engineers do. For HT12E (Encoder)
Use a Microcontroller : Program an Arduino Uno or PIC16F877A to output the HT12E protocol:
8 address bits (A0-A7) 4 data bits (AD8-AD11) A sync pulse (12 cycles low, then high) Create a Sub-circuit Model (Most reliable for simulation)
Or use a "Pattern Generator" : In Proteus, use the PATTERN source to simulate the serial output waveform.
For HT12D (Decoder)