XR28V382IL32-0A Datasheet, PDF (4/39 Pages) Exar Corporation – 3.3V DUAL LPC UART WITH 128-BYTE FIFO

XR28V382
3.3V DUAL LPC UART WITH 128-BYTE FIFO
Pin Description
REV. 1.0.1
NAME
32-QFN
PIN#
TYPE
DESCRIPTION
DSRA#
16
I
UART Channel A Data-Set-Ready (active low) or general purpose input. This
input should be connected to VCC or GND when not used.
RIA#
17
I
UART Channel A Ring-Indicator (active low) or general purpose input. This input
should be connected to VCC or GND when not used.
CDA#
18
I
UART Channel A Carrier-Detect (active low) or general purpose input. This input
should be connected to VCC or GND when not used.
RTSA# /
PS_CONF_2E/
26
RS485
UART Channel A Request-to-Send (active low) or general purpose output.
O ^{This pin has an internal pull-up resistor and is sampled upon power-up or reset.}
The registers can later be modified by the software. See Table 1 ’UART Power
On Configuration’.
DTRA# /
27
PS_3E0_IRQA
UART Channel A Data-Terminal-Ready (active low) or general purpose output.
This pin has an internal pull-up resistor and is sampled upon power-up or reset.
O _{This will determine the default register settings for UART Channel A. The regis-}
ters can later be modified by the software. See Table 1 ’UART Power On Con-
figuration’.
RXA
28
I
UART Channel A Receive data.The receive data input must idle at logic 1 condi-
tion. This input should be connected to VCC or GND when not used.
TXA /
29
PS_3F8_IRQA
UART Channel A Transmit Data. The TXA signal will be a logic 1 during reset or
idle (no data). If it is not used, leave it unconnected.
O ^{This pin has an internal pull-up resistor and is sampled upon power-up or reset.}
This will determine the default register settings for UART Channel A. The regis-
ters can later be modified by the software. See Table 1 ’UART Power On Con-
figuration’.
IRRXA#
30
I
Infrared Receiver input. The infrared receive data input idles at logic 0. This input
should be connected to GND when not used.
IRTXA#
31
O
Infrared Transmitter output. The IRTXA# signal will be a logic 0 during reset or
idle (no data).
ANCILLARY SIGNALS
CLKIN
9
I Clock input 24 MHz or 48 MHz.
WDTOUT#/
PS_WDT
19
Active low watchdog timer output. This pin is open drain and needs a pull-up
O resistor if it is used. The registers can later be modified by the software. See
Table 1 ’UART Power On Configuration’.
POWER SIGNALS
VCC
8, 21 Pwr 3.3V ± 10% power supply.
GND
1, 20
Pwr Power supply common, ground.
GND
Center
Pad
The center pad on the back side of the QFN package is metallic and should be
connected to GND on the PCB. The thermal pad size on the PCB should be the
Pwr approximate size of this center pad and should be solder mask defined. The sol-
der mask opening should be at least 0.0025" inwards from the edge of the PCB
thermal pad.
Pin type: I=Input, O=Output, I/O= Input/output, Pwr=Power supply.
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