The HT1621 is a 128 pattern (32x4), memory mapping, and multi-function LCD driver. The S/W configuration feature of the HT1621 makes it suitable for multiple LCD applications including LCD modules and display sub-systems. Only three or four lines are required for the in- terface between the host controller and the HT1621. The HT1621 can be controlled by a 3-wire serial interface to receive commands and data from the host controller to achieve various LCD control.
The HT1621 is a 128‑pattern (32×4) LCD driver designed for a wide range of LCD applications. It includes a built‑in 256 kHz RC oscillator, optional 32.768 kHz crystal, and selectable bias configurations. The device supports a 3‑wire serial interface, multiple data access modes, and two buzzer frequencies (2 kHz/4 kHz).
The datasheet provides detailed pin assignments, absolute maximum ratings, DC and AC electrical characteristics, functional descriptions of the system oscillator, time‑base and watchdog timer, tone output, and LCD driver commands. Package options include 48‑pin SSOP, DIP, LQFP, and 28‑pin SKDIP variants.