The flexible RGB LED colour change possibilities can implement breathing lighting effects using the fully internal hardware circuits. This makes these highly functionally integrated MCUs suitable for use in colour RGB LED products such as RGB Gaming Keyboards, RGB Gaming Mice, RGB LED Speakers, etc. These devices eliminate the need for external PWM components resulting in lower costs and reduced product development times.

The HT66FB572 and HT66FB574 devices include 8K and 16K×16-bits of Program Memory respectively, 256 bytes of Data EEPROM and 1K bytes of RAM Data Memory. With regard to connecting with external hardware the devices include SPI, I2C and UART interfaces. They also include an 8 and 12-channel 12-bit A/D Converter and two LED PWM Data Memory sections each having a capacity of 256 bytes respectively. The hardware can automatically calculate the PWM duty cycle according to the data written into a dedicated Data Memory area to implement LED colour changes and breathing effects.

These new devices now offer extended functions over the already released HT66FB5x0 and HT68FB5x0 device series. They are provided with an ISP online firmware update function using its USB interface and also support ICP, ISP and IAP modes to provide a means for easy and fast development for USB related peripheral products.