User's Manual

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ABOUT THE DEVELOPMENT BOARD
Power supply
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Power supply
The development board provides a 3.3V
DC
switching power supply. Either a bench
power supply or an AC wall adapter supplies input power to the development board.
The required input voltage range is 9–30V
DC
.
Input power jack,
J3
The input power jack, J3, is a barrel connector that accepts 9-30 VDC. The power
jack is labeled J3 on the development board. This figure schematically represents
the power jack’s polarity:
Input power
supply
The output current of this regulator is limited to 2.4 amps and the Digi Connect Wi-
Wave 802.11 b/g module draws no more than .750 amps. Using these values as a
guideline, and using an 80% efficiency for the switching regulator, the input power
supply should be rated to provide at least 3 watts of power.
Important: The development board can use USB power as the power source for the
3.3V regulator. This is accomplished by simply connecting the USB
cable to the development board. However, Digi recommends using the
supplied AC wall adapter.
Ground 9-30VDC +/- 5%