Prop 1 to cowlacious audio

[Scott Carter]

I have a prop 1 connected to a CAR/P 300 audio board and the prop1 is powering the car/p300 as you showed in one of your diagrams. However, I find need to turn off the car/p300 periodically with the prop1 code. My 1st thought was a relay triggered by one of the outputs to interrupt power, but then I wondered if I could just power the car/p 300 by using an output held high. Too much power? Any other options? I also have LEDs on it that are taking about 200ma.

[JonnyMac]

You should might want check with Cowlacious on the current draw for that board; if it's 200mA or less then you can switch it with the ULN without any problems.

[Edit] I just unpacked my CAR/P-200 and found that it draws about 32mA while playing.  I can't imagine the the -300 draws much more than this so you should be safe switching it with the ULN.  Remember that the V+ goes to the + side of the power input and the OUTx terminal to the - side.

Note to AP-8 users: You can't do this with the AP-8 because the AP-8's amplifier requires more power than the ULN is able to supply.  The Cowlacious boards are not amplified.