MGC3130 – Sabrewing Evaluation Board
2013 Microchip Technology Inc.
DS41685A-page 21
3.4
I
2
C™ TO USB BRIDGE
The communication between the MGC3130 and the host PC is controlled by the I
2
C to
USB Bridge
section. The message exchange is handled by Microchip’s PIC18F14K50
USB microcontroller. The PIC18F14K50 is also used to indicate the communication
status on a LED bar and to control MGC3130 hardware Reset.
The board is powered via the USB port. Microchip’s Low Dropout (LDO) Voltage
Regulator MCP1801 is used to transform the 5V USB power to 3.3V required for the
MGC3130 and the PIC18F14K50.
The LEDs indicate the following:
• POWER – signals that the Sabrewing board is powered (3.3V)
• LED1/2 – blink simultaneously to indicate that there is no data transfer on the USB
port
• LED1/2 – blink alternating to indicate that there is data transfer on the USB port
• LED 5 – is on when there is data on the I
2
C bus
• LEDs 0, 3, 4, 6 and 7 are not used
