HT16511 -- 1/8 to 1/16 Duty VFD Controller

General Description
HT16511 is a VFD (Vacuum Fluorescent Display) controller/driver that is driven on a 1/8 to 1/16 duty factor. It consists of 12 segment output lines, 8 grid output lines, 8 segment/grid output drive lines, 5 LED output ports, a control circuit, a display memory, and a key scan circuit.
Serial data inputs to the HT16511 through a three-line serial interface. This VFD controller/driver is ideal as a peripheral device for an MCU.

Features
Logic voltage: 5V
High-voltage output: VDD-35V max.
Multiple display (12-segment & 16-digit to 20-segment & 8-digit)
12x4 matrix key scanning
8 steps dimmer circuit
5 LED output ports (20mA max.)
4-bit general purpose input port
No external resistors necessary for driver output (provides PMOS open-drain and
pull-low resistor output)
Serial interface with MCU (CLK, CSB, DI, DO)
52-pin QFP package