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EB007 SWITCH Board
More information can be found here.
EB007 SWITCH Board Block Diagram
- Click EB007-30-1 for a datasheet.
- The male D-type connector fits into the Female connector of one of the ports of an upstream board.
- The Female connector is here to connect several boards in parallel.
- Switch pressed:
- Small current flow through 390R-SW and 4K7.
- Voltage over 4K7 is +/- 4.7V is a clear '1' for the input pin of the PICmicro
- Switch not pressed:
- No current flow
- No voltage over 4K7 resistor
- This is a clear '0' for the input of the PICmicro
- BEWARE!!!
- All pins of the PICmicro can be configured either as an input or as an output.
- This is where the resistor of 390R is important:
- If you accidentally configure a pin as a low output and connect a switch to it then the 390R resistor limits the current into the PICmicro to (5V/390R) = 12mA.
- Be aware of this when you design your own circuits!
- This is well under the Imax of 25mA.
- If the 390R resistor would not have been in this circuit, there would have been no current limitation at all resulting in at least a broken PICmicro microcontroller.
- This is further explained in the drawing below. In this specific case the current will follow the orange path.
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