The STC89C516RD-40I with STC LQFP-44_10x10x08P RoHS is a microcontroller produced by STC. It is an 8-bit single chip microcontroller with a maximum operating frequency of 40MHz. It has 32KB of Flash ROM, 1KB of EEPROM, 1KB of OTP, and 128 bytes of RAM. It has several I/O interfaces such as UART, SPI, USB, I2C, PWM, etc. It also has 4Kbytes of LDROM. The RoHS variant of this microcontroller is specifically designed to meet stricter environmental regulations. It is a lead-free, low-power component and it is certified for use in a variety of ways for global products.