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DEMOEM User Manual
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Layout for jumper from board VDD to MCU VDD pins, with layout for
an optional zero ohm resistor to permanently connect these signals.
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Layout for jumper from MCU VDD to MCU VDDA and from MCU VSS
to MCU VSSA pins, with populated zero ohm resistor shorting jumper
pins.
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Layout for jumper from MCU VDDA to MCU VREFH and from MCU
VSSA to MCU VREFL pins, with populated zero ohm resistor shorting
jumper pins
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All power traces are minimum double width
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Four test points for GND
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Four test point for VDD
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Voltage input jumpers
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powered DEMO via on-board voltage regulator (3.3V)
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powered DEMO via on-board USB BDM (3.3V)
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powered DEMO via on-board battery (3.0V)
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supply 3.3V power to the MCU_PORT header if the board is
powered though the on-board regulator or USB
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Noise filter in the VDD to VDDA, VSS and VSSA connection in order
to improve ADC accuracy
MCU:
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Reset switch with optional LED indicator.
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IRQ Button
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Crystal circuit for 32kHz to 16MHz crystal for XOSC2 input (not
populated)
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Use circuit components recommended by crystal manufacturer
and MCU data sheet.
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Footprint for jumpers to disable XTAL from MCU
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0 ohm resistors in parallel with jumper footprints to connect XTAL
circuit
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Jumpers to disable all the user I/O functions from additional circuitry