xr20v2170 Exar Corporation, xr20v2170 Datasheet - Page 4

• Manufacturer Part Number: xr20v2170
• Description: I2c/spi Uart With 64-byte Fifo And Rs232 Transceiver
• Manufacturer: Exar Corporation

Pin Description
XR20V2170
I2C/SPI UART WITH 64-BYTE FIFO AND RS232 TRANSCEIVER
N
MODEM OR SERIAL I/O INTERFACE (EIA-232/RS-232 Voltage Levels)
Ancillary signals (CMOS/TTL Voltage Levels)
OTE
VREF+
VREF-
N
GND
RXD
TXD
DTR
DSR
CTS
ACP
N.C.
RTS
C2+
C1+
C2-
C1-
: Pin type: I=Input, O=Output, I/O= Input/output, OD=Output Open Drain.
CD
AME
RI
-
indicates a voltage in the range 0V to VIL and ’HIGH" indicates a voltage in the range VIH to VCC. For RS-232
input voltage levels, ’LOW’ is any voltage < 1.5V and ’HIGH’ is any voltage > 3V. For RS-232 output voltage levels,
’LOW’ is any voltage < -5V and ’HIGH’ is any voltage > 5V.
9, 19, 24, 25,
31, 32, 33
7, 17, 26
40-QFN
P
PAD
10
11
12
38
39
15
20
21
29
30
22
34
IN
3
1
4
#
T
Pwr
Pwr
Pwr
Pwr
I/O
I/O
YPE
O
O
-
-
-
I
I
I
I
I
UART Data-Set-Ready. This input has an internal pull-down resistor and can be
left unconnected when not used.
UART Receive Data. UART receive data input must idle LOW. 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 during reset or idle (no data).
UART Request-to-Send or general purpose output. This output must be asserted
prior to using auto RTS flow control, see EFR[6], MCR[1] and IER[6].
UART Data-Terminal-Ready. If this pin is unused, it should be left unconnected.
UART Clear-to-Send or general purpose input. 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.
UART Carrier-Detect or general purpose input. This input has an internal pull-
down resistor and can be left unconnected when not used.
UART Ring-Indicator or general purpose input. This input has an internal pull-
down resistor and can be left unconnected when not used.
Autosleep for Charge Pump (active HIGH). When this pin is HIGH, the charge
pump is shut off if the V2170 is already in partial sleep mode, i.e. the crystal
oscillator is stopped.
Charge pump capacitors. As shown in
placed between these 2 pins.
Charge pump capacitors. As shown in
placed between these 2 pins.
-5.0V generated by the charge pump.
+5.0V generated by the charge pump.
Power supply common, ground.
The center pad on the backside of the QFN packages is metallic and is not elec-
trically connected to anything inside the device. It must be soldered 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 sol-
der mask defined. The solder mask opening should be at least 0.0025" inwards
from the edge of the PCB thermal pad.
No Connection.
4
D
ESCRIPTION
Figure
Figure
For CMOS/TTL Voltage levels, ’LOW’
1, a 0.1 uF capacitor should be
1, a 0.1 uF capacitor should be
REV. 1.0.0