The STC11F04E-35I-SOP20 with STC SOIC-20_300mil RoHS is an 8-bit CMOS microcontroller unit (MCU) manufactured by STC. It has a maximum supply voltage of 3.6V and is programmed using standard 8051 instruction set. The device has 128 bytes of RAM, 4K bytes of program memory, 32 I/Os, two 16-bit timers/counters, one 8-bit timer, three 16-bit PWM outputs, one UART channel, one SPI port, and one I2C port. It is built in 8-bit CPU with advanced single-cycle instruction execution and low power dissipation. It is suitable for applications requiring low-power consumption, noise immunity, and small size. The RoHS version of the device is Pb-free and is compliant with the restriction of the usage of hazardous substances in electrical and electronic equipment.