Parameter

Symbol

Value

Unit

Supply voltage

VCC

+7

V

Voltage of control port

/RE, DE, DI

-0.3~+7

V

Bus side input voltage

A, B

-7~13

V

Receiver output voltage

RO

-0.3~+7

V

Operating temperature range

-40~85

°C

Storage temperature range

-60~150

°C

Welding temperature

300

°C

Continuous power dissipation

SOP8

400

mW

MSOP8/8μMAX/VSSMAX/VSSOP8

830

mW

DIP8

700

mW

The maximum limit parameter value means that exceeding these values may cause irreversible

damage to the device. Under these conditions, it is not conducive to the normal operation of the

device. Continuous operation of the device under the maximum allowable rating may affect the

reliability of the device. The reference point of all voltages is ground.

Pin functions

Pin number

Pin name

Pin function

1

RO

Receiver output

When /RE is low level: if A-B

≧ 200mV, RO = high;

if A-B

≦ -200mV, RO = low

2

/RE

Receiver output enable control

When /RE is low level, receiver output is enabled, and RO output is

available.

When /RE is high level, receiver output is disabled, and RO is in high

impedance state.

When /RE is high level and DE is low level, the device enters low power

consumption mode.

3

DE

Driver output enable control

When DE is high level, driver output is available; when DE is low level, the

output is in high impedance state.

When /RE is high level and DE is low level, the device enters low power

consumption mode.

4

DI

Driver input

When DE is high level, the DI low level forces the non-inverting driver

output A low and inverting driver output B high;

The DI high level forces the non-inverting driver output A high and

inverting driver output B low.

5

GND

Ground

6

A

Non-inverting receiver input and non-inverting driver output

7

B

Inverting receiver input and inverting driver output

8

VCC

Power supply

Limiting values

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友台半导体有限公司

ST3485E

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

RS485/RS422 transceiver

UMW R