5

LTC1485

PI FU CTIO S

RO (Pin 1): Receiver Output. If the receiver output is

enabled (RE low), then if A > B by 200mV, RO will be high.

If A < B by 200mV, then RO will be low.

RE (Pin 2): Receiver Output Enable. A low enables the

receiver output, RO. A high input forces the receiver

output into a high impedance state.

DE (Pin 3): Driver Output Enable. A high on DE enables the

driver outputs, A and B. A low input will force the driver

outputs into a high impedance state.

DI (Pin 4): Driver Input. If the driver outputs are enabled

(DE high), then a low on DI forces the driver outputs A low

and B high. A high on DI will force A high and B low.

GND (Pin 5): Ground Connection.

A (Pin 6): Driver Output/Receiver Input.

B (Pin 7): Driver Output/Receiver Input.

TEST CIRCUITS

Figure 3. Receiver Timing Test Load

1k

1485 F03

S1

S2

1k

RECEIVER

OUTPUT

Figure 4. Driver Timing Test Load

1485 F04

S1

S2

500

Ω

OUTPUT

UNDER TEST

A

B

R

R

1485 F01

DI

1485 F02

DRIVER

RECEIVER

RO

15pF

A

B

A

B

Figure 1. Driver DC Test Load

Figure 2. Driver/Receiver Timing Test Circuit