Electrical – A Voltage Divider with Load Regulation and Efficiency Question?

loadregulationsvoltage divider

For this question, the voltage divider splits the 12 V battery into +/- 6 V and it supplies up to 10 W total to the load, split between the two output voltage outputs in an arbitrary ration. Load regulation is intended to be greater than 1% from 0 W to 10 W. Now, in this case, the resistors, R, aren't the load resistors, the load resistors would be connected in parallel to the resistors, R

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Now, what I need help on is approaching this problem. I think I managed to get the load resistors correct at 3.6 Ohms from 10 W / ((6 V)^2) but I'm not too sure

Best Answer

The regulation of 1% should be taken into account when loads (not shown in your schema) are connected to this awful 'regulator'. Since you need 1% regulation, the current through the resistors for your divider should be 100 times greater than the current through the load.

Each LOAD would be 3.6 Ohm in the worst case (10Wx2 transferred to the load). The resistors on the divider should be 100 times smaller, namely, 0.036 Ohm each. So your VERY hypothetical divider would be consuming 2kW!!!. Your battery would be discharged in no time, the resistors of your divider would be bulky things heating the environment like a home radiator... so it should be obvious that the voltage divider solution is not applicable for any application that requires a significant amount of power to be transferred. As a rule of thumb, if the resistors of your divider are smaller than 1K each you should probably consider another solution.