XR16C2450 Datasheet, PDF (5/31 Pages) Exar Corporation – 2.97V TO 5.5V DUART

xr
REV. 1.0.0
Pin Description
NAME
40-PDIP
PIN #
RIB#
23
OP2B#
13
ANCILLARY SIGNALS
XTAL1
16
XTAL2
17
RESET
35
VCC
40
GND
20
N.C.
-
XR16C2450
2.97V TO 5.5V DUART
44-PLCC
PIN #
26
15
48-TQFP
PIN #
21
9
TYPE
DESCRIPTION
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.
O Output Port 2 Channel B - The output state is defined by
the user and through the software setting of MCR[3].
INTB is set to the active mode and OP2B# output to a
logic 0 when MCR[3] is set to a logic 1. INTB is set to the
three state mode and OP2B# to a logic 1 when MCR[3] is
set to a logic 0. This output should not be used as a gen-
eral output else it will disturb the INTB output functionality.
If it is not used, leave it unconnected.
18
13
19
14
39
36
44
42
22
17
1, 12, 23,
34
6, 12, 18,
24, 25, 31,
37, 43
I Crystal or external clock input.
O Crystal or buffered clock output.
I Reset (active high) - A longer than 40 ns logic 1 pulse on
this pin will reset the internal registers and all outputs. The
UART transmitter output will be held at logic 1, the
receiver input will be ignored and outputs are reset during
reset period.
Pwr 2.97V to 5.5V power supply. All inputs are 5V tolerant.
Pwr Power supply common, ground.
- No Connection.
Pin type: I=Input, O=Output, IO= Input/output, OD=Output Open Drain.
5