XR20M1172G28-0B Datasheet, PDF (5/55 Pages) Exar Corporation – TWO CHANNEL I2C/SPI UART WITH 64-BYTE FIFO

REV. 1.2.0
Pin Description
XR20M1172
TWO CHANNEL I2C/SPI UART WITH 64-BYTE FIFO
NAME
GPIO7/RIA#
VCC
A0/CS#
A1/SI
I2C/SPI#
-
NC
32-QFN
PIN #
28
29
30
31
32
PAD
1, 8
28-TSSOP
PIN#
TYPE
DESCRIPTION
28
I/O _{General purpose I/O pin or UART Ring-Indicator. If this pin is an input}
and is unused, it should be connected to VCC or GND. If this pin is an
output and is unused, it should be left unconnected. See IOControl[1]
and IODir register.
1
Pwr _{1.62V to 3.63V power supply.}
2
I _I2_{C-bus device address select A0 or SPI chip select. If I}2_{C-bus config-}
uration 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).
3
I _I2_{C-bus device address select A1 or SPI data input pin. If I}2_C-bus
onfiguration 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.
4
I _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
-
Pwr _{The center pad on the backside of the QFN package is metallic and is}
not electrically connected to anything inside the device. It must be sol-
dered on to the PCB and may be optionally connected to GND on the
PCB. The thermal pad size on the PCB should be the approximate
size of this center pad and should be solder mask defined. The solder
mask opening should be at least 0.0025" inwards from the edge of the
PCB thermal pad.
-
- _{No Connection.}
Pin type: I=Input, O=Output, I/O= Input/output, OD=Output Open Drain.
5