USB 2.0 Hi-Speed 4-Port Hub Controller
Datasheet
2014 Microchip Technology Inc. DS00001713A-page 15
1
UART
Receive Input
UART_RX IS Internal UART receive input
Note: This is a 3.3V signal. For RS232
operation, an external 12V translator is
required.
Port 3 Over-
Current
Sense Input
OCS3_N IS
(PU)
This active-low signal is input from an external
current monitor to indicate an over-current
condition on USB Port 3.
1
UART
Transmit
Output
UART_TX O8 Internal UART transmit output
Note: This is a 3.3V signal. For RS232
operation, an external 12V driver is
required.
Port 4 Over-
Current
Sense Input
OCS4_N IS
(PU)
This active-low signal is input from an external
current monitor to indicate an over-current
condition on USB Port 4.
1
System Reset
Input
RESET_N I_RST This active-low signal allows external hardware to
reset the device.
Note: The active-low pulse must be at least
5us wide. Refer to Section 8.3.2,
"External Chip Reset (RESET_N)," on
page 37 for additional information.
1
Crystal Input XTAL1 ICLK External 24 MHz crystal input
Reference
Clock Input
REFCLK ICLK Reference clock input. The device may be
alternatively driven by a single-ended clock
oscillator. When this method is used, XTAL2
should be left unconnected.
1
Crystal
Output
XTAL2 OCLK External 24 MHz crystal output
1
External USB
Transceiver
Bias Resistor
RBIAS AI A 12.0kΩ (+/- 1%) resistor is attached from
ground to this pin to set the transceiver’s internal
bias settings.
1
LED 0 Output LED0 O8 General purpose LED 0 output that is
configurable to blink or “breathe” at various rates.
Note: LED0 must be enabled via the Protouch
configuration tool.
Table 3.1 Pin Descriptions (continued)
NUM PINS NAME SYMBOL
BUFFER
TYPE DESCRIPTION
