MSKSEMI MSHT1622(LQFP64)

MSHT1622 is a memory-mapped, 256-point dot-matrix multi-function LCD driver IC. Its software architecture makes it suitable for dot-matrix LCD display applications, including LCD modules and display subsystems. The circuit features a power-down function to reduce power consumption. It is controlled via a microcontroller interface and performs a clear reset upon power-up. Operating states are configured through the command port; RAM data is read, written, and modified via chip select, read, and write operations, driving the LCD display on a one-to-one mapping basis. Each segment driver operates independently, enabling flexible modification of display content and supporting user customization. The static display RAM is organized as 64×4 bits, storing display data that maps directly to the LCD driver. Data is written to RAM via read, write, and read-modify-write commands. The timebase generator and watchdog timer share a divide-by-256 counter, with independent controls for enable, disable, clear, and interrupt enable/disable. When the watchdog timer overflows, the IRQ pin is held low until a clear-watchdog or disable-interrupt command is received. If an external clock source is selected, the system disable command has no effect; the system will not enter low-power mode unless the external clock is removed. An internal buzzer circuit generates a pair of complementary drive signals for piezoelectric buzzers; the buzzer frequency can be selected via command as either 2kHz or 4kHz, with on/off control available. The circuit is configured through serial software, and instructions for setting and transferring display data are divided into two modes: command mode and data mode. Command mode is used for system configuration; data mode is used for data operations. The interface comprises 4 lines: chip select for initializing and terminating communication; data line for serial input/output; read clock for latching data on the falling edge; write clock for latching data, addresses, and commands on the rising edge; and an interrupt request line for outputting timebase or watchdog timer overflow flags. It is recommended that the host controller initialize the MSHT1622 after power-on reset to prevent erroneous operation.

• Operating voltage range: 2.7V ~ 5.2V
• Built-in 32kHz RC oscillator circuit
• Supports 1/4 bias, 1/2 duty cycle, display frequency 64Hz
• Integrated resistor-type bias voltage generation circuit
• Two buzzer frequency options: 2kHz or 4kHz
• Power-down command support for reduced power consumption
• Integrated time base and watchdog timer circuit
• Time base/watchdog timer overflow output
• 8 clock source options for time base/watchdog timer
• LCD driver supporting up to 32×8 dot matrix
• 3-wire serial interface
• Address auto-increment support
• Three data access modes
• VLCD pin for LCD voltage adjustment
• Package: 64-pin QFP/LQFP, 44-pin LQFP