The FT61F135-TRB TSSOP-20 RoHS Other Processors and Microcontrollers (MCUs) manufactured by Fremont Micro Devices is a low-voltage, high-speed 8-bit single-chip microcontroller based on the MCS-51 instruction set. It is designed specifically for applications requiring easy modification and low power consumption. This device operates from 3V to 5V, making it perfect for battery operated and low-voltage appliances. The FT61F135-TRB supports up to 128 bytes of built-in data flash memory, 64 bytes of RAM, and up to eight general purpose I/O ports. With an operation frequency up to 12MHz, the FT61F135-TRB can complete instructions in 2 clock cycles to improve execution speed. This device also supports multi-periodic interrupts for quick interrupts as well as a watchdog timer, which prevents system crashes due to malfunctions in programs. The FT61F135-TRB is available in a package that is minimized to fit narrow board space.