The device includes a 4kHz~1MHz IR carrier frequency generator. Together with the Holtek supplied development tools, four common IR carrier frequencies of 36, 38, 40 or 56kHz can be selected. The internal oscillator frequency can be trimmed to 3.996, 3.99, 4.0, or 3.976MHz, allowing the frequency error to be effectively reduced to ensure better matching of the transmitter and receiver carrier frequencies and thus increasing the IR transmission range.

The device has an operating voltage range of 1.8V~5.5V and includes a Flash program memory capacity of 1Kx13 and a RAM data memory capacity of 32x8. The device also provides a 9-bit Timer as well as Time Base functions. The fully internal 4MHz oscillator has a high precision frequency specification with a tolerance of ±0.4% at a voltage range of 1.8V~5.5V and with an operating temperature of -10℃ ~ 50℃. This oscillator is used as the MCU main system clock allowing the device to operate with a more accurate frequency. The device is supplied in 8-pin SOP, 16-pin NSOP, 20-pin NSOP and 20-pin SSOP package types.