The BS83B24C and BS83C40C respectively provide 24 and 40 touch keys. Both devices include an integrated hardware accelerator circuit to improve the touch key algorithm execution efficiency. They also include SPI, I2C and UART interfaces as well as an RTC clock function. They are available in 28-pin SOP/SSOP, 28-pin SOP/SSOP and 44-pin LQFP package types.

The devices can be used as master MCU devices on their own or can work alongside an external master MCU to implement a touch key detection system. Holtek also supports these devices with a comprehensive suite of hardware and software development tools. These tools include a touch key function library which enables designers to develop their products more rapidly by eliminating the need to write software for the touch key functions. The hardware development tool is known as the e-Link which works together with an OCDS evaluation MCU whose functions and packages are fully compatible with the actual MCU thus providing full hardware emulation during product development.