XR21V1412 Datasheet, PDF (5/24 Pages) Exar Corporation – 2-CH FULL-SPEED USB UART

REV. 1.0.0
Pin Description
XR21V1412
2-CH FULL-SPEED USB UART
NAME
32-QFN
PIN #
TYPE
DESCRIPTION
GPIOB3/DTRB# ¹⁹
I/O _{General purpose I/O or UART Data-Terminal-Ready output (active low). This pin has}
an internal pull-up resistor. Internal pull-up resistor is disabled during suspend mode.
If using this GPIO as an input, a pull-up resistor is required to minimize the power
consumption in the suspend mode.
GPIOB4/CTSB# ¹⁸
I/O _{General purpose I/O or UART Clear-to-Send input (active low). This pin has an inter-}
nal pull-up resistor. Internal pull-up resistor is disabled during suspend mode. If
using this GPIO as an input, a pull-up resistor is required to minimize the power con-
sumption in the suspend mode.
GPIOB5/RTSB# ¹⁷
I/O _{General purpose I/O or UART Request-to-Send output (active low). This pin has an}
internal pull-up resistor. Internal pull-up resistor is disabled during suspend mode. If
using this GPIO as an input, a pull-up resistor is required to minimize the power con-
sumption in the suspend mode.
USB Interface Signals
USBD+
30
USBD-
29
I/O _{USB port differential data plus. This pin has a 1.5 K Ohm internal pull-up resistor.}
I/O _{USB port differential data minus.}
I2C Interface Signals
SDA
25
SCL
26
OD _I2_{C-controller data input/output (open-drain). 1K pull-up resistor is required. An}
optional external I²C EEPROM can be used to store default configurations upon
power-up including the USB Vendor ID and Device ID.
If an EEPROM is not used, this pin can be used with the SCL pin to select the
Remote Wake-up and Power modes. An external pull-up or pull-down resistor is
required. See Table 1.
I _I2_{C-controller serial input clock. 1K pull-up resistor is required. An optional external}
I²C EEPROM can be used to store default configurations upon power-up including
the USB Vendor ID and Device ID.
If an EEPROM is not used, this pin can be used with the SDA pin to select the
Remote Wake-up and Power modes. An external pull-up or pull-down resistor is
required. See Table 1.
Ancillary Signals
LOWPOWER
2
O _{Low power status output. This pin is HIGH when the XR21V1412 is in the suspend}
mode. This pin is LOW when the XR21V1412 is not in the suspend mode. An exter-
nal pull-up or pull-down resistor is required on this pin. This pin is sampled upon
power-on to configure the polarity of the LOWPOWER output during suspend mode.
An external pull-up resistor will cause the LOWPOWER pin to be HIGH during sus-
pend mode. An external pull-down resistor will cause the LOWPOWER pin to be
LOW during suspend mode
VCC
4, 13, 24, Pwr _{+3.3V power supply. All inputs are 5V tolerant.}
31, 32
GND
1, 3, 14, Pwr _{Power supply common, ground.}
23, 27,
28
NOTE: Pin type: I=Input, O=Output, I/O= Input/output, OD=Output Open Drain.
5