xr16l2550im Exar Corporation, xr16l2550im Datasheet - Page 4

• Manufacturer Part Number: xr16l2550im
• Description: Industry Smallest Package Uart With 2.25v To 5.5v Operation
• Manufacturer: Exar Corporation

Pin Description
XR16L2550
LOW VOLTAGE DUART WITH 16-BYTE FIFO
MODEM OR SERIAL I/O INTERFACE
TXRDYB#
RXRDYB#
CTSA#
DTRA#
DSRA#
OP2A#
RTSA#
CDA#
N
RIA#
RXA
RXB
TXA
TXB
AME
32-QFN
P
23
25
IN
5
4
6
3
-
-
-
-
-
-
-
#
44-PLCC
P
12
23
13
11
36
40
37
41
42
43
35
14
10
IN
#
48-TQFP
P
18
33
38
34
39
40
41
32
IN
6
7
5
8
4
#
T
YPE
O
O
O
O
O
O
O
I
I
I
I
I
I
UART channel B Transmitter Ready (active low). The output pro-
vides the TX FIFO/THR status for transmit channel B. If it is not
used, leave it unconnected.
UART channel B Receiver Ready (active low). This output pro-
vides the RX FIFO/RHR status for receive channel B. If it is not
used, leave it unconnected.
UART channel A Transmit Data. If it is not used, leave it uncon-
nected.
UART channel A 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.
UART channel A Request-to-Send (active low) or general pur-
pose output. This output must be asserted prior to using auto
RTS flow control, see EFR[6], MCR[1] and IER[6]. If it is not
used, leave it unconnected.
UART channel A Clear-to-Send (active low) or general purpose
input. It can be used for auto CTS flow control, see EFR[7] and
IER[7]. This input should be connected to VCC when not used.
UART channel A Data-Terminal-Ready (active low) or general
purpose output. If it is not used, leave it unconnected.
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.
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.
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.
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 func-
tionality. If it is not used at all, leave it unconnected.
UART channel B Transmit Data. If it is not used, leave it uncon-
nected.
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.
4
D
ESCRIPTION
REV. 1.1.2