XR16V794 Datasheet, PDF (5/53 Pages) Exar Corporation – HIGH PERFORMANCE 2.25V TO 3.6V QUAD UART WITH FRACTIONAL

REV. 1.0.0
XR16V794
HIGH PERFORMANCE 2.25V TO 3.6V QUAD UART WITH FRACTIONAL BAUD RATE
NAME
TX3
RX3
PIN #
28
21
RTS3#
26
CTS3#
22
DTR3#
27
DSR3#
23
CD3#
24
RI3#
25
ANCILLARY SIGNALS
XTAL1
50
XTAL2
49
TMRCK
31
ENIR
32
RST#
20
16/68#
19
VCC
GND
9,30,52
10,29,51
TYPE
DESCRIPTION
O ^{UART channel 3 Transmit Data or infrared transmit data. Normal TXD output idles}
HIGH while infrared TXD output idles LOW.
I ^{UART channel 3 Receive Data or infrared receive data. Normal RXD input idles}
HIGH while infrared RXD input idles LOW. In the infrared mode, the polarity of the
incoming RXD signal can be selected via FCTR bit-4. If this bit is a logic 0, a LOW
on the RXD input is considered a mark and if this bit is a logic 1, a HIGH on the
RXD input is considered a space.
O UART channel 3 Request to Send or general purpose output (active low). See
description of RTS0# pin.
I UART channel 3 Clear to Send or general purpose input (active low).d. See
description of CTS0# pin.
O UART channel 3 Data Terminal Ready or general purpose output (active low). See
description of DTS0# pin.
I UART channel 3 Data Set Ready or general purpose input (active low). See
description of DSR0# pin.
I UART channel 3 Carrier Detect or general purpose input (active low).
I UART channel 3 Ring Indicator or general purpose input (active low).
I Crystal or external clock input. Caution: this input is not 5V tolerant.
O Crystal or buffered clock output.
I 16-bit timer/counter external clock input.
I Infrared mode enable (active high). This pin is sampled during power up, following
a hardware reset (RST#) or soft-reset (register RESET). It can be used to start up
all 4 UARTs in the infrared mode. The sampled logic state is transferred to MCR bit-
6 in the UART.
I Reset (active low). The configuration and UART registers are reset to default val-
ues, see Table 19.
I Intel or Motorola data bus interface select. HIGH selects Intel bus interface and
LOW selects Motorola interface. This input affects the functionality of IOR#, IOW#
and CS# pins.
+2.25V to 3.6V supply with 5V tolerant serial (modem) inputs.
Power supply common, ground.
NOTE: Pin type: I=Input, O=Output, IO= Input/output, OD=Output Open Drain.
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