33790

The 33790 is intended for use in a DSI system. This device supplies the interface between standard logic levels and the voltage and current required for the DSI bus. Two independent DSI busses are supported by this part. The 33790 does not form the timing for the DSI bus. This is done by logic either embedded in a microcontroller or by the MC68HC55, which uses SPI commands and forms DSI protocol for communications over the DSI bus.

The pins from the MC68HC55 are made to line up with the pins connecting to the 33790. This includes all the DSIxF,
DSIxS, and DSIxR pins.

A capacitor attached to CPCAP serves as a charge reservoir for the gate drive charge pump. This circuit creates a voltage that is higher than the source of the N-channel output transistor. This allows turning on of the transistor enough to prevent any significant voltage drop across it. The rest of charge pump electronics are completely self-contained on the IC.

The 33790 is a two-channel physical layer interface IC for the Distributed System Interface (DSI) bus. 33790 is designed to meet automotive requirements. It can also be used in nonautomotive applications. 33790 supports bidirectional communication between slave and master ICs. Some slave devices derive a regulated 5.0 V from the bus, which can be used to power sensors, thereby eliminating the need for additional circuitry and wiring.