HV633

The HV633 is a 32-channel driver IC for gray shade display use. It is designed to produce varying output voltages between 3 and80 volts. This amplitude modulation at the output is facilitated by  n external ramp voltage V_R. See Theory of Operation for detailed explanation.

This device HV633 consists of a dual 16-bit shift registers, 32 data latches  and comparators, and control logic to preform 128 levels of gray shading. There are 7 bits of data inputs. Data is shifted through the shift registers at both edges of the clock, resulting a data transfer rate of twice of the shift clock frequency. When the DIR pin is high, CSI/CSO is the input/output for the chip select pulse. When DIR is low, CSI/CSO is the output/input for the chip select pulse. The DIR = HIGH also allows the HV633 to shift data in the counterclockwise direction when viewed from the top of the package.

When the DIR pin of HV633 is low, data is shifted in the clockwise direction. he output circuitry allows the energy which is stored in the output capacitance to be returned to V_PP through the body diode of the output transistor.