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Part Number 74C922-SO

Copyright © 2014 ABCircuits. Revised September 2014 Page 1 of 8

SIO8 IC

Stand Alone UART IC

8 bits of input and 8 bits of output

General Description

The SIO8 IC is a stand alone UART designed to provide 8 bits of input and output data to connect

to RS-232, USB, RS-485, Ethernet or directly to your UART. Outputs can be used to drive relays,

logic, optocouplers or a transistors. Inputs can be from switches, relay contacts, logic,

optocouplers or a transistor switched to ground. The SIO8 has internal pull resistors on most

inputs to minimize additional parts. If the MODE pin is open or high, the data on the IA0-7 pins

are transmitted only after a byte is received on the SIN- pin. If the MODE pin is low, the SIO8 IC

transmits data anytime the inputs change or every of 100 mS, or 1000 mS, depending on the

state of the SPD pin. A positive pulse is generated on the RXP pin every time a byte is received

on the SIN- pin. The serial format to the SIO8 is standard asynchronous format, using 8 bits, 1

stop and no parity at 9600 BPS. Other formats and encoding are available, contact the factory.

A .1 uF bypass capacitor is suggested across the VDD and VSS pins. The part uses the standard

28 pin .3 inch width SOIC package.

Features

bits of input and 8 bits of output.

USB or Ethernet or UART.

contacts, optocouplers, and logic.

most inputs.

transistors, optocouplers, and logic.

typical.

Applications