I/O Controller Interface 32-Pin SOIC

The 33781 is a master device for four differential DSI 2.02 buses. It contains the logic to interface the buses to a standard serial peripheral interface (SPI) port and the analog circuitry to drive data and power over the bus, as well as receive data from the remote slave devices. The differential mode of the 33781 generates lower electromagnetic interference (EMI) in situations where data rates and wiring make this a problem. Frequency spreading further reduces interference by spreading the energy across many frequencies, reducing the energy in any single frequency.

Four independent differential DSI (DBUS) channels

Dual SPI interface

Enhanced bus fault performance

Automatic message cyclical redundancy checking (CRC) generation and checking for each channel

Enhanced register set with addressable buffer allows queuing of 4 independent slave commands at one time for each channel

8- to 16-Bit messages with 0- to 8-Bit CRC

Independent frequency spreading for each channel

Pseudo bus switch feature on channel 0