XR20V2172 Datasheet, PDF (3/51 Pages) Exar Corporation – TWO CHANNEL I2C/SPI UART WITH 64-BYTE FIFO AND RS232 TRANSCEIVER

PRELIMINARY
XR20V2172
REV. P1.0.1
TWO CHANNEL I2C/SPI UART WITH 64-BYTE FIFO AND RS232 TRANSCEIVER
PIN DESCRIPTIONS
Pin Description
NAME
64-QFN
PIN #
TYPE
DESCRIPTION
I2C (SPI) INTERFACE
I²C/SPI#
61
SDA
2
SCK
33
A0/
57
CS#
A1/
59
SI
SO
64
IRQ#
38
RESET#
52
I/O _I2_{C-bus or SPI interface select. I}2_{C-bus interface is selected if this pin is}
HIGH. SPI interface is selected if this pin is LOW.
I/O _I2_{C-bus data input/output (open-drain). If SPI configuration is selected,}
then this pin is undefined and must be connected to VCC.
I
I²C-bus or SPI serial input clock.
When the I²C-bus interface is selected, the serial clock idles HIGH.
When the SPI interface is selected, the serial clock idles LOW.
I
I²C-bus device address select A0 or SPI chip select. If I²C-bus configura-
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
I²C-bus device address select A1 or SPI data input pin. If I²C-bus onfigu-
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.
O _{SPI data output pin. If SPI configuration is selected then this pin is a}
three-stateable output pin. If I²C-bus configuration is selected, this pin is
undefined and must be left unconnected.
OD _{Interrupt output (open-drain, active LOW).}
I
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.
SERIAL I/O INTERFACE (CMOS/TTL Voltage Levels)
RXB
7
I
UART Channel B Receive Data. This pin can be used to communicate
with external IR or RS-232 transceiver.
TXB
8
O _{UART Channel B Transmit Data. This pin can be used to communicate}
with external IR or RS-232 transceiver.
MODEM OR SERIAL I/O INTERFACE (EIA-232/RS-232 Voltage Levels)
RXDA
RXDB
39
I
UART Receive Data. UART receive data input must idle LOW (< 1.5V).
29
This input has an internal pull-down resistor and can be left unconnected
when not used.
TXDA
TXDB
42
O _{UART Transmit Data. The TX signal will be LOW (< 1.5V) during reset or}
27
idle (no data).
RTSA
RTSB
28
O _{UART Request-to-Send. This output must be asserted prior to using auto}
5
RTS flow control, see EFR[6], MCR[1] and IER[6].
CTSA
CTSB
63
I
UART Clear-to-Send. It can be used for auto CTS flow control, see
4
EFR[7], MSR[4] and IER[7]. This input has an internal pull-down resistor
and can be left unconnected when not used.
3