TCA8424 Datasheet PDF – 8×16, Keyboard Scanner

Part Number: TCA8424

Function: Low-Voltage 8×16 Keyboard Scanner with HID over I2C Compliant Interface

Package: RSM/RHB 32 Pin Type , RHA 40 Pin Type

Manufacturer: Texas Instruments


TCA8424 datasheet



This 128 key scan device is specifically targeted towards end equipment that runs on Windows 8 operating system. The device is fully compliant with the HID over I2C specification defined (ver 1.0) defined by Microsoft. The HID and report descriptors are hard coded into the device so that they don’t need to be programmed at production. The device also comes with a preprogrammed keyboard map that is compatible with most standard laptop/notebook keyboards. However, the device also available without a pre-programmed keyboard, so that any keyboard map may be written into it at production.

The device generates INPUT reports of standard 8-byte length with the 1st byte being the modifier byte. After the keyboard map is programmed into the device it automatically  recognizes the row/column location of the modifier keys based on their usage code. It is capable of detecting and reporting up to six simultaneous key presses plus eight modifiers. It generates an input report on each key press and each key release.



1. Supports FM+ I2C Operation up to 1MHz

2. Can Support up to 128 (8×16) Key Scan

3. Internal Power-On-Reset

4. Open Drain Open Drain Active Low INT Output

5. Noise Filter on SCL/SDA and Inputs

6. Open Drain Outputs Can Sink up to 12mA


TCA8424 Datasheet PDF Download

TCA8424 pdf

Other data sheets are available within the file: TCA8424RHAR