XR22804 Datasheet, PDF (6/47 Pages) Exar Corporation – Hi-Speed USB to 10/100 Ethernet Bridge with 4 UARTs

XR22804
Pin No.
Pin Name
6
E28/CTSD#/GD4
7
CAP1
8
GND
9
USBD–
10
USBD+
11
VCC
12
E26/DSRD#/GD2
13
ETH_SPD
14
E27/DTRD#/GD3
15
XTALOUT
16
XTALIN
17
E24/RID#/RWKD#/GD0
18
E25/CDD#/GD1
19
3V3_OUT
20
GND
21
ETH_TX–
22
ETH_TX+
23
ETH_RX+
24
ETH_RX–
25
E22/RXC/RWKC#
26
E23/TXC
27
E21/RTSC#/RS485C/GC5
28
E20/CTSC#/GC4
29
E0/RIA#/RWKA#/GA0
30
E1/CDA#/GA1
Type
I/O
I
PWR
I/O
I/O
PWR
I/O
O
I/O
O
I
I/O
I/O
PWR
PWR
O
O
I
I
I/O
I/O
I/O
I/O
I/O
I/O
Description
Enhanced general purpose IO, or UART channel D Clear to Send, or general purpose IO.
Defaults to UART GPIO input except when XR22804 is used with CDC-ACM driver. Refer to
Automatic RTS/CTS Hardware Flow Control section on page 15.
Connect externally to CAP2 and 3V3_OUT using short trace
Power supply common, ground
USB port differential data negative
USB port differential data positive
5.0V power supply input
Enhanced general purpose IO, or UART channel D Data Set Ready, or general purpose IO.
Defaults to UART GPIO input. Refer to Automatic DTR/DSR Hardware Flow Control section
on page 16.
Ethernet 10/100 Mbps Speed Indicator. Asserted high for 100 Mbps.
Enhanced general purpose IO, or UART channel D Data Terminal Ready, or general purpose
IO. Defaults to UART GPIO input. Refer to Automatic DTR/DSR Hardware Flow Control sec-
tion on page 16.
Crystal or buffered clock output
25 MHz +/- 50 ppm Crystal or external clock input
Enhanced general purpose IO, or UART channel D Ring Indicator, or remote wakeup, or gen-
eral purpose IO. Defaults to UART GPIO input. Refer to Remote Wakeup section on page 11.
Enhanced general purpose IO, or UART channel D Carrier Detect, or general purpose IO.
Defaults to UART GPIO input.
3.3 V output power. Connect externally to CAP1 and CAP2 using short trace and decouple
with minimum of 4.7uF capacitor
Power supply common, ground
Ethernet transmit data out negative
Ethernet transmit data out positive
Ethernet receive data in positive
Ethernet receive data in negative
Enhanced general purpose IO, or UART channel C RX data, or remote wakeup. Defaults to
UART RX data.
Enhanced general purpose IO, or UART channel C TX data. Defaults to UART TX data.
Enhanced general purpose IO, or UART channel C Request to Send, or channel C auto-
RS485 half-duplex enable, or general purpose IO. Defaults to UART GPIO input except when
XR22804 is used with CDC-ACM driver. Refer to Automatic RTS/CTS Hardware Flow Control
section on page 15 or Auto RS-485 Half-Duplex Control on page 16.
Enhanced general purpose IO, or UART channel D Clear to Send, or general purpose IO.
Defaults to UART GPIO input except when XR22804 is used with CDC-ACM driver. Refer to
Automatic RTS/CTS Hardware Flow Control section on page 15.
Enhanced general purpose IO, or UART channel A Ring Indicator, or remote wakeup, or gen-
eral purpose IO. Defaults to UART GPIO input. Refer to Remote Wakeup section on page 11.
Enhanced general purpose IO, or UART channel A Carrier Detect, or general purpose IO.
Defaults to UART GPIO input.
© 2015 Exar Corporation
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exar.com/XR22804
Rev 1B