Still if you could find a 0.4-v battery somewhere of approximately the same current capacity you could connect in opposition to your 1.5'er
In order to pragmatically deal with the OP's question, an answer to Contrex is needed..
Off hand I do not know of any commerce battery with anywhere near a cell value of .4 volts.
perhaps the load is so small that throwing half the power always would not be a problem.
That's why we have to hear from Slim Jim
dalehileman wrote:Maybe he went away and read about Ohm's Law, and/or voltage regulators and he now understands what he needs to do. Seeing the 0.65 volt requirement makes me think he wants to drive an LED or maybe some kind of low power chip.That's why we have to hear from Slim Jim
Footnote I remember dealing with the worst design ever where a 400 volts supply was used with a 20 watts wirewound resister and a 35 volt zener in order to get a 35 voltage reference source!!!!!!!!
Talk about throwing away power for not good reason as there was any number of lower voltages tap offs from the transformer that could had been used.
the source voltage and the load voltage does not in and of itself dictate the power loss due to voltage regulation.
most importantly you would use a current limiting resistor (dropping resistor) in series with the LED so that the current rating of the LED is not exceeded
you can use a DC to DC switching regulator
Quote:the source voltage and the load voltage does not in and of itself dictate the power loss due to voltage regulation.
You kidding me correct as power equal voltage time current and the power being wasted in the case I referred to is 400-35 volts time Current compare to the useful power of 35 volts time current.
So to sum up that design is wasting 365/400 or 91 percents of the total power being used.
Now if instead if a DC to DC step down design had been used then yes indeed the situation would had been far better as far as power being thrown away is concern and the voltage in compared to the voltage out would not have such a linear relationship to the power being wasted.
I stand 100% by what I said. The fact that you wish to reference current calculations is pure straw man. Moreover I expect that you quote me in full should you wish me to explain further (not that I overly mind explaining).
difference between the source voltage and the load voltage does not in and of itself dictate the power loss due to voltage regulation.