The software configuration feature of the HT16L21 device makes it suitable for multiple LCD applications including LCD modules and display subsystems. The  HT16L21 device communicates with most microprocessors/microcontrollers via a two-wire bidirectional I2C or a three-wire SPI interface.

• Logic operating voltage: 1.8V~5.5V
• LCD operating voltage (VLCD): 2.4V~6.0V
• External VLCD pin to supply LCD operating voltage
• Internal 32kHz RC oscillator
• Bias: 1/2 or 1/3; Duty:1/4
  Internal LCD bias generation with voltage-follower buffers
• Integrated regulator to adjust LCD operating voltage: 3.0V, 3.2V, 3.3V, 3.4V, 4.4V, 4.5V, 4.6V, 5.0V
• Integrated LED driver
• Support I2C or SPI 3-wire serial interface
  controlled by IFS pin
• Four selectable LCD frame frequencies:
  64Hz or 85.3Hz or 128Hz or 170.6Hz
• 32×4 bits RAM for display data storage
• Max. 32×4 pixel: 32 segments and 4 commons
• Support two driver output mode segment/LED on SEG24~SEG31/LED7~LED0
• Versatile blinking modes: off, 0.5Hz, 1Hz, 2Hz
• R/W address auto increment
• Low power consumption
• Manufactured in silicon gate CMOS process
• Package types: 44LQFP