Start: 10:15

• Continued working on drawing out the circuit board.  I think I can do this one sided but if not I can definitely do it with two sides.  The cost doesn’t go up much unless you use the 2 internal layers.
• Finished drawing the sensor circuits and added ports for the varios wire groups coming in and out of the board.
• Just a reminder because I think I forgot to mention this in earlier entries.  Each board supports 2 fingers, so one board will only have half the components on it.  The reason for this is the rheostat is I2c.  I2c protocol only allows 4 addresses for slave devices.  Another reason this works out is our high powered amplifiers are stereo.
• Phil suggested using barrel plugs for the power.  I figure if we are going to do this, we might as well have one power input and regulate the power on the circuits that require 5v.
• I tested a circuit for a LM7905 Voltage Regulator.  The surface mounted ones use a metal plate to increase heat conductivity with the pcb board allowing for much smaller packaging.
• The 5V circuit will be running parallel to the 12V amplifier.  There are two things that need to be considered to make this work in a robust manner.  First a load resistor will have to be added to the 5 volt side to bring the current going in down to 1 Amp which is the operating capacity of the voltage regulator.  Second, I have to worry about what will happen if the amp suddenly stops working causing a surge of power to the regulator.  I believe a RC circuit to ground resolves this problem.

End:6:15