Similar to the HT66FB5x0 and HT68FB5x0 series, this new device is compatible with the USB 2.0 specification and has an operating voltage of 2.2V to 5.5V, an operating temperature of -40°Cto +85°C thus meeting with industrial specifications. The system clock is derived from either an external crystal or a fully internal high speed RC oscillator circuit with a fixed frequency of 12 MHz.

The device has a Program Memory capacity of 4Kx16 and 256 bytes of Data Memory RAM. It includes a Full Speed USB interface with up to 4 USB endpoints as well as up to 17 bidirectional I/Os, 4 Timer Modules with PWM outputs, dual SPI interfaces, an I2C slave interface, a Watchdog Timer, a Low Voltage Detect function, a 4-channel 12-bit high-precision A/D converter as well as a comparator.

In addition, it also contains an internal regulator with a 3.3V output which can be used by peripheral applications. The device is supplied in a 24-pin SSOP package.

Holtek has provided the device with a new ISP online firmware update function. The firmware can be easily updated via the USB interface using the I3000 Writer (Windows®-based). Holtek also provides a DLL for user development. The full series also provides ICP, ISP and IAP programming support.

Holtek also supplies a full suite of excellent hardware and software development tools known as the HT-IDE3000 (Windows®-based) which includes a hardware In-Circuit Emulator with full trace analysis features as well as many other functions. Used together with the OCDS debug interface, Holtek also offers a range of application guides to ensure developers have their designs up and running in the shortest time possible.