A module that allows you to use a second power supply for subsequent bits in a circuit.
Proof of Concept:
As you can see from the one minute movie above, the module performs as expected, at least with two number bits.. The signal of the second half follows the signal of the first, but each number bit has it's own, independent power supply. Having a separate power supply should (should!) allow a high current bit, such as a servo motor, run more smoothly.
I said should in italics because in fact, this circuit does not perform as expected at high current levels. When I add a servo motor to the end of the circuit, it works fine up to about 75% of full voltage. But when the number bits say 75 or greater, the motor goes wild, lurching from right to left, and the number bit turns on and off. I put the circuit on an ammeter, and the current of the servo side bounced between zero and 200mA, while the the other side drew a steady 20-ish mA.)
Here's the schematic of the breadboard:
Simple/dimple, right? No wonder it doesn't work. I believe the main problem is due to the op-amp I used– or rather, abused. The maximum output current of the TLV2462 is 80 milliamps. The servo bit can draw 200mA or more when it starts to move. The op-amp gets over amped and checks out, then the current falls and it jerks back, and oscillates between maximum and zero milliamps.
I need to solve the current problem that @alexpikkert hinted at in this post.