The BS83B series of touch key flash MCU series from Holtek contains three devices; the BS83B08-3 with 8 touch keys, the BS83B12-3 with 12 touch keys and the BS83B16-3 with 16 touch keys.
The touch key functions are implemented using internal oscillator circuits and timers. When human contact is detected, the change in oscillator external capacitance results in a change of oscillator frequency leading to a resulting change in a timer value. This feature coupled with a channel encoder for multiple-channel scanning, enables the touch key functions within the BS83B series to detect which switches have been touched.
External reference capacitors are not required with switch sensitivity being adjusted by the application program.
The BS83B device series provides 2Kx15 of flash program memory, three internal system oscillator frequency selections of 8MHz, 12MHz and 16MHz and a combined SPI/I²C communication interface which allows the BS83B series devices to act as both master and slave terminals.
Other features include, 160 bytes of RAM and up to 13 I/O pins in the BS83B08-3, 288 bytes of RAM and up to 17 I/O pins in the BS83B12-3 and 288 bytes of RAM and up to 21 I/O pins in the BS83B16-3.
This BS83B flash MCU devices are suitable for use in numerous multiple switch home appliance applications such as blenders, extractors, electric pressure cookers, disinfecting machines, and intelligent refrigerators.
An internal watchdog timer and low voltage reset functions provide immunity against malfunction or erroneous operation. The BS83B08-3 is supplied in a 16-pin NSOP package while the BS83B12-3 is available in 20-pin SOP/SSOP packages and the BS83B16-3 is available in a 24-pin SOP/SSOP package.