ST3485E

●

1

R

8

4

D

5

3.3V power supply, up to 256 nodes, 12Mbps half-duplex,

RS485/RS422 transceiver

Features:



3.3V power supply, half-duplex;

 1/8 unit load allows up to 256 devices on the bus;

 Driver output short-circuit protection function;

 Over temperature protection function;



Low power shutdown function;



Receiver open circuit protection function;



Strong anti-noise ability;

 Integrated transient voltage resistance function;



Transmission rate up to 12Mbps in an electrical noise environment;

Description

The ST3485E is a 3.3V powered, half-duplex, low-power RS-485 transceiver that fully meets the

requirements of the TIA/EIA-485 standard.

The ST3485E includes a driver and a receiver, both of which can be independently enabled and

disabled. When both are disabled, both the driver and the receiver output a high impedance state. The

ST3485E has a 1/8 load that allows 256 ST3485E transceivers to be connected to the same

communication bus. Error-free data transfer of up to 12Mbps is possible.

The ST3485E operates from a voltage range of 3.0 to 3.6V and features fail-safe, over

temperature protection, current limit protection, over-voltage protection, and other functions.

Pin configuration

RO

VCC

RE

B

DE

A

DI

GND

Figure 1 ST3485E pin configuration

UMW R

www.umw-ic.com

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友台半导体有限公司