XR32430EUCRTR-F Datasheet, PDF (11/14 Pages) Exar Corporation – 3-Driver/5-Receiver Intelligent RS-232 Transceiver with 1.65V-5.5V Interface

XR32430/XR32431
When the XR32430/31 is shut down, the charge pumps are turned off. V+ charge pump output decays to V_CC, the V- output
decays to GND. The decay time will depend on the size of capacitors used for the charge pump. Once in shutdown, the time
required to exit the shut down state and have valid V+ and V- levels is typically 30μs.
For easy programming, the STATUS can be used to indicate DSR or a Ring Indicator signal. Tying ONLINE and SHUT-
DOWN together will bypass the AUTO ON-LINE® circuitry so this connection acts like a shutdown input pin.
Valid
RS-232
Level at
Receiver
Input
Yes
No
Yes
No
Yes
No
Table 2: XR32430/31 Operation Truth Table
Shutdown
OnLine
Driver Receiver
Outputs Outputs
Status
Mode of Operation
L
x
High-Z High-Z
H Manually forced shutdown
L
x
High-Z High-Z
L Manually forced shutdown
H
L
Active Active
H Normal Operation
(Auto On-Line® enabled)
H
L
High-Z Active
L Standby Operation due to
Auto On-Line® circuitry
H
H
Active Active
H Normal Operation
H
H
Active Active
L Normal Operation
Table 3: XR32430/31 Driver and Receiver Truth Table
Shutdown
RxIN
RxOUT
TxIN
TxOUT
L
x
High-Z
x
High-Z
H
L
H
L
H
H
H
L
H
L
© 2014 Exar Corporation
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