28301 Parallax Inc, 28301 Datasheet

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... PWR-I/O-DB Power and I/O Daughterboard (#28301) General Description The PWR-I/O-DB daughterboard provides convenient interfacing between a Parallax motherboard and various external devices, including servos, serial LCDs, and potentiometers. Before using your PWR-I/O-DB, please read and understand this entire document. Features Compact size: plugs into, and matches the footprint of, Parallax motherboards. ...

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Interface Connections and Jumpers "Power Good" LED External Power Connector External Power Connector The external power connector enables the connection of a filtered, unregulated 6-9VDC power supply to power the motherboard. An example would be Parallax’s 7.5V wall transformer (#750-00009). ...

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This option is only available if the daughterboard is plugged into the motherboard’s “A” socket. There is no Vin connection to the “B” socket. Important: When the Vin/J1 jumper is in place, never connect power ...

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Important: The power provided at the external device headers is always +5V, regardless of your Vdd selection on the motherboard. This may have unintended consequences if your motherboard is running with a Vdd of 3.3V. For most devices where the ...

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Serial devices can communicate directly with the BASIC Stamp on headers A2, A3, P8, and P9. They can communicate with the AVR on headers A0, A1, A2, and A3, but requires the appropriate AVR firmware to be ...

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USB/EXT 5V/3.3V 5V USB 3. EXT 3.3V 5V USB 3. EXT 3.3V “Reg” stands for “regulator”; “Int” , for “internal”. * Use a divider to divide fullscale output to 1.1V. Voltages above ...

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Analog Output The AVR offers two PWM outputs, which, with filtering, can be converted to an analog voltage. The Propeller offers duty-cycle outputs, which can also be filtered to yield an analog voltage. The illustrations below show a couple analog ...

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Schematic © Parallax, Inc. • PWR-I/O-DB (2006.09.13) Page ...