Hi Jon, The usual method of getting a variable DC is to use a resistor-capacitor combination on the PWM output to get an average DC value. Seve...

Switching converters are a good choice, especially when your battery voltage is a lot higher than the load voltage, but they are larger, heavier, and ...

Hi Jbo, You may have a problem with that regulator. It is rated for 8V and up on the input, and will not produce 6 volts with only 7.4 in. A low dro...

If you change the 5 volts to 15 volts, and go through the calculation for resistor values you should get R2 = 0.66667 R1 and R1 = 6667. Therefore R2 w...

@will You are correct, however the same method can be used by placing the expected input impedance in parallel with R3. Or simply assign a lower va...

@will Hi Will, The design is intended for use with an analog to digital converter in a teensy processor. I assume the input impedance for this de...

Hello Jon, The best way to use the 15 volt supply would be to just change resistor values to allow using +15 volts for the reference instead of 5 vo...

Yes, you could use almost any op amp that can handle the voltage in your power supplies. The only exception might be if you have very high frequency r...

Hi Jon, There is a simpler way to do this with a voltage divider. The calculation of resistor values gets a bit messy, but here is a circuit that wi...

Hello Jon, The same circuit can be used to do what you want with a few minor changes. Your output load requirements seem to be a lot lower than the ...

You are probably correct, the best solution is to incorporate a class B push-pull output. The attached schematic shows one option for this. Three op a...

@davee You are correct, perhaps a second transistor or a smaller resisitor would be required. U forgot it needed to go to negative 10 volts. 270 oh...

Dave makes a good point that I missed. If you need more current for the load, you can add a simple emitter follower to the circuit (Q1, R10). This tra...

Hello Jon, An op amp would work well for this application. The attached schematic shows one way to do the job. Since you want to amplify the input v...

This motor should work fine if you gear it so the motor torque is adequate for the job. Timing belts and pulleys or a lead screw are good options. Use...