The HT66F0025 is a low power 8-bit microcontroller with advanced built-in features, manufactured by Holtek. This microcontroller comes in a standard 150-mil SOP-8 form factor and is RoHS compliant. The device has 8K bytes of program memory, 128 bytes of data memory and up to 64 bytes of extended data memory. It supports a variety of peripherals including three 16-bit timers, a 10-bit A/D converter, a comparator, three sets of I/O ports, watchdog timer, two serial ports and one SPI port. In addition, its power saving features include low power modes and multiple clock sources. The device is widely used in consumer, automotive, industrial and medical applications.