Power Supply

[behrendfry]

I need to design a circuit that can power a device(s) which vary in their input voltages. The issue is they all use the same connector but throughout the years as the device has been improved the power source changed. I would like to make an external power source for these devices that will accomidate each one. The three different inputs are 8VDC max for the first generation, 10VDC min for the second generation and now 12VDC min for the third generation. I would like to be able to have batteries stored in a carrying device with the 1 connector that does mate up with every generation of the device but when I plug in the connector to the device I want it to be able to use the correct power source(8, 10 0r 12 Vdc). Someone mentioned to me this can be done easily using trim resistors....any suggestions on a simple and inexpensive way to do this?

 

[Optikon]

I need to design a circuit that can power a device(s) which vary in their input voltages. The issue is they all use the same connector but throughout the years as the device has been improved the power source changed. I would like to make an external power source for these devices that will accomidate each one. The three different inputs are 8VDC max for the first generation, 10VDC min for the second generation and now 12VDC min for the third generation. I would like to be able to have batteries stored in a carrying device with the 1 connector that does mate up with every generation of the device but when I plug in the connector to the device I want it to be able to use the correct power source(8, 10 0r 12 Vdc). Someone mentioned to me this can be done easily using trim resistors....any suggestions on a simple and inexpensive way to do this?

what about one 12V power source and LDO regulators for the 8 and 10V? 12V goes straight through. 8 & 10 come from regulators (powered by 12)

Linear regulators are low cost and can be small physically (depending on load requirements) but are inefficient. Efficiency might be a concern of yours though unless you batteries need to last a long time.

For high efficiency 8 & 10V supplies, use switching regulators.