Product description
The 3.6865 MHz crystal is used almost exclusively as a reference crystal for asynchronous serial communication (UART/RS-232/TTL UART).
The frequency is chosen because it is an integer multiple of common baud rates. 3.6865 MHz divided by 16 gives 230.4 kHz, which can then be divided exactly into 115200, 57600, 38400, 19200, 9600 baud and further downward. This results in low frequency deviation and a stable time base for serial communication without rounding errors.
Typical areas of use include microcontroller systems where precise UART timing is required, older PC-related hardware with an external crystal for UART circuits, and embedded systems with RS-232 or TTL serial communication.
