xr20v2172 Exar Corporation, xr20v2172 Datasheet - Page 3

• Manufacturer Part Number: xr20v2172
• Description: Two Channel I2c/spi Uart With 64-byte Fifo And Rs232 Transceiver
• Manufacturer: Exar Corporation

REV. 1.0.0
PIN DESCRIPTIONS
Pin Description
I2C (SPI) INTERFACE
SERIAL I/O INTERFACE (CMOS/TTL Voltage Levels)
MODEM OR SERIAL I/O INTERFACE (EIA-232/RS-232 Voltage Levels)
I
RESET#
2
RXDA
RXDB
TXDA
TXDB
CTSA
CTSB
RTSA
RTSB
N
C/SPI#
IRQ#
SDA
SCK
RXB
CS#
TXB
A0/
A1/
SO
AME
SI
64-QFN
P
61
33
57
59
64
38
52
39
29
42
27
28
63
TWO CHANNEL I2C/SPI UART WITH 64-BYTE FIFO AND RS232 TRANSCEIVER
IN
2
7
8
5
4
#
T
OD
I/O
I/O
YPE
O
O
O
O
I
I
I
I
I
I
I
I
HIGH. SPI interface is selected if this pin is LOW.
I
then this pin is undefined and must be connected to VCC.
I
When the I
When the SPI interface is selected, the serial clock idles LOW.
I
tion is selected, this pin along with the A1 pin allows user to change the
device’s base address. If SPI configuration is selected, this pin is the SPI
chip select pin (Schmitt-trigger, active LOW).
I
ration is selected, this pin along with A0 pin allows user to change the
device’s base address. If SPI configuration is selected, this pin is the SPI
data input pin.
SPI data output pin. If SPI configuration is selected then this pin is a
three-stateable output pin. If I
undefined and must be left unconnected.
Interrupt output (open-drain, active LOW).
Reset (active LOW) - A longer than 40 ns LOW pulse on this pin will reset
the internal registers and all outputs. The UART transmitter output will be
idle and the receiver input will be ignored.
UART Channel B Receive Data. This pin can be used to communicate
with external IR or RS-232 transceiver.
UART Channel B Transmit Data. This pin can be used to communicate
with external IR or RS-232 transceiver.
UART Receive Data. UART receive data input must idle LOW (< 1.5V).
This input has an internal pull-down resistor and can be left unconnected
when not used.
UART Transmit Data. The TX signal will be LOW (< 1.5V) during reset or
idle (no data).
UART Request-to-Send. This output must be asserted prior to using auto
RTS flow control, see EFR[6], MCR[1] and IER[6].
UART Clear-to-Send. It can be used for auto CTS flow control, see
EFR[7], MSR[4] and IER[7]. This input has an internal pull-down resistor
and can be left unconnected when not used.
2
2
2
2
2
C-bus or SPI interface select. I
C-bus data input/output (open-drain). If SPI configuration is selected,
C-bus or SPI serial input clock.
C-bus device address select A0 or SPI chip select. If I
C-bus device address select A1 or SPI data input pin. If I
2
C-bus interface is selected, the serial clock idles HIGH.
3
2
D
C-bus configuration is selected, this pin is
ESCRIPTION
2
C-bus interface is selected if this pin is
XR20V2172
2
C-bus configura-
2
C-bus onfigu-