Figure 1. Operating principle of a capacitive touch key: Fingers typically touch the electrode through the panel, resulting in an increase in total capacitance, CS.
The BS21xC-x series includes the BS211C-1, BS212C-1, BS213C-1, BS214C-1, BS214C-2, BS216C-1, BS218C-2, and BS218C-3 models, all of which offer excellent development convenience. This allows developers to quickly and directly implement them in touch key product applications without needing to invest time in understanding touch key technology. The device's internal circuitry can perform automatic calibration based on environmental changes, further improving its accuracy and stability in touch detection. In addition, the BS211C-1, BS216C-1, BS218C-2, and BS218C-3 devices include an IRQ pin option, providing another level of application flexibility.
The BS21xC-x series provides 1 to 8 tactile keys. With a suitable packaging design and output interface, these devices can meet the requirements of various electronic product applications. All are backward compatible with the pinout of the previous BS81xC-x series, enabling easy upgrades and thus shortening the product development cycle, resulting in lower overall costs. Table 1 summarizes the parameters of the new BS21xC-x series models and some from the older BS81xC-x series.
