XR16L2450 Datasheet, PDF (4/30 Pages) Exar Corporation – 2.25V TO 5.5V DUART

XR16L2450
2.25V TO 5.5V DUART
PIN DESCRIPTIONS
NAME
44-PLCC 48-TQFP
PIN #
PIN #
CTSA#
40
38
DTRA#
37
34
DSRA#
41
39
CDA#
42
40
RIA#
43
41
OP2A#
35
32
TXB
14
8
RXB
10
4
RTSB#
27
22
CTSB#
28
23
DTRB#
38
35
DSRB#
25
20
CDB#
21
16
RIB#
26
21
xr
REV. 1.1.0
TYPE
DESCRIPTION
I UART channel A Clear-to-Send (active low) or general purpose input.
This input should be connected to VCC when not used. This input has
no effect on the UART.
O UART channel A Data-Terminal-Ready (active low) or general purpose
output. If it is not used, leave it unconnected.
I UART channel A Data-Set-Ready (active low) or general purpose input.
This input should be connected to VCC when not used. This input has
no effect on the UART.
I UART channel A Carrier-Detect (active low) or general purpose input.
This input should be connected to VCC when not used. This input has
no effect on the UART.
I UART channel A Ring-Indicator (active low) or general purpose input.
This input should be connected to VCC when not used. This input has
no effect on the UART.
O Output Port 2 Channel A - The output state is defined by the user and
through the software setting of MCR[3]. INTA is set to the active mode
and OP2A# output to a logic 0 when MCR[3] is set to a logic 1. INTA is
set to the three state mode and OP2A# to a logic 1 when MCR[3] is set
to a logic 0. This output should not be used as a general output else it
will disturb the INTA output functionality. If it is not used at all, leave it
unconnected.
O UART channel B Transmit Data. If it is not used, leave it unconnected.
I UART channel B Receive Data. Normal receive data input must idle at
logic 1 condition. If it is not used, tie it to VCC or pull it high via a 100k
ohm resistor.
O UART channel B Request-to-Send (active low) or general purpose out-
put. If it is not used, leave it unconnected.
I UART channel B Clear-to-Send (active low) or general purpose input.
This input should be connected to VCC when not used. This input has
no effect on the UART.
O UART channel B Data-Terminal-Ready (active low) or general purpose
output. If it is not used, leave it unconnected.
I UART channel B Data-Set-Ready (active low) or general purpose input.
This input should be connected to VCC when not used. This input has
no effect on the UART.
I UART channel B Carrier-Detect (active low) or general purpose input.
This input should be connected to VCC when not used. This input has
no effect on the UART.
I UART channel B Ring-Indicator (active low) or general purpose input.
This input should be connected to VCC when not used. This input has
no effect on the UART.
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