SP304 Datasheet, PDF (11/12 Pages) Sipex Corporation – RS-232/RS-422 Line Drivers/Receivers

nects the driver outputs to the corresponding
receiver inputs, and switches the output pin to a
high impedance from V_EE to ground. Receiver
outputs are left active for signal verification.
During loopback, the receiver inputs are tied to
ground via a 5kΩ pulldown resistor. The re-
ceiver inputs can accept the full ±15V swings
with no interference to the loopback function.
SP304 CONFIGURATIONS IN LOOPBACK MODE
One-Channel Full Duplex RS-232 &
One-Channel Full Duplex RS-422
Opposite Drivers
Two-Channel Full Duplex RS-422
TIB₂
TIB₁
RS-232 LINE DRIVERS
RS-232 RECEIVERS
ROB₂
ROB₁
TOB₂
TOB₁
RIB₂
RIB₁
TIA₁
TOA₂
TOA₁
RS-422 LINE DRIVER
RS-422 RECEIVER
ROA₁
RIA₁
RIA₂
SELECT A = 1
SELECT B = 0
LB = 0 ^(ACTIVE)
Corporation
SIGNAL PROCESSING EXCELLENCE
TIB₁
RS-422 LINE DRIVERS
RS-422 RECEIVERS
ROB₁
TOB₂
TOB₁
RIB₁
RIB₂
TIA₁
TOA₂
TOA₁
RS-422 LINE DRIVERS
RS-422 RECEIVERS
ROA₁
RIA₁
RIA₂
SELECT A = 1
SELECT B = 1
LB = 0 ^(ACTIVE)
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