ST485A

Pin configuration

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1

Pin configuration

Figure 1.

Pin configuration

1.1

Pin description

Table 1.

Pin description

Pin

n°

Symbol

Name and function

1RO

Receiver output. If A>B by 200mV, RO will be high; if A<B by 200mV, RO will be

low

2RE

Receiver output enable. RO is enabled when RE is low; RO is high impedance

when RE is high. If RE is high and DE is low, the device will enter a low power

shutdown mode.

3DE

Driver output enable. The driver outputs are enabled by bringing DE high. They are

high impedance when DE is low. If RE is high DE is low, the device will enter a low-

power shutdown mode. If the driver outputs are enabled, the part functions as line

driver, while they are high impedance, it functions as line receivers if RE is low.

4DI

Driver input. A low on DI forces output A low and output B high. Similarly, a high on

DI forces output A high and 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