SN75138

四路总线收发器

The SN55138 and quadruple bus transceivers are designed for two-way data communication over single-ended transmission lines. Each of the four identical channels consists of a driver with TTL inputs and a receiver with a TTL output. The driver open-collector output is designed to handle loads up to 100-mA open collector. The receiver input is internally connected to the driver output, and has a high impedance to minimize loading of the transmission line. Because of the high driver-output current and the high receiver-input impedance, a very large number typically hundreds of transceivers may be connected to a single data bus.

The receiver design also features a threshold of 2.3 V typical, providing a wider noise margin than would be possible with a receiver having the usual TTL threshold. A strobe turns off all drivers high impedance but does not affect receiver operation. These circuits are designed for operation from a single 5-V supply and include a provision to minimize loading of the data bus when the power-supply voltage is zero.

The SN55138 is characterized for operation over the full military temperature range of -55°C to 125°C. The SN75138 is characterized for operation from 0°C to 70°C.

.

Single 5-V Supply

.

High-Input-Impedance, High-Threshold Receivers

.

Common Driver Strobe

.

TTL-Compatible Driver and Strobe Inputs With Clamp Diodes

.

High-Speed Operation

.

100-mA Open-Collector Driver Outputs

.

Four Independent Channels

.

TTL-Compatible Receiver Output