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covert 3V battery source to 1.5 V Answered

hi Guys,

I have a 3V battery source and want to convert it to 1,5V to run a device.

How do I go about doing it?
Will a voltage divider work accurately?

8 Replies

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Orngrimm (author)2013-03-13

I can second Bobbel Headeinstein.
A divider is a bad idea since a voltage divider (consisting of 2 resistors) is only accurate if you have a steady load (like none at all or always the same) tapped from this divider...
Go with the suggested LM317 linear regulator.
If you want maximum efficiency, you can go with a more complex but 95-99% efficient DC/DC-Converter. See http://www.linear.com/product/LTC3549 for an example...

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user
Bobblehead Einstein (author)2013-03-11

try using a 1.5 volt regulator,that should work

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user

LM317 should do you good,it is a adjustable voltage regulator

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user

Will the connection be something like this?
http://www.circuitstoday.com/wp-content/uploads/2011/04/LM317-typical-adjustable-regulator-ckt.png

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user

Yes
all you need to do is determine resister values for your 1.5v output
The capacitor's(represented as C1 & C2) are not a necessary but i would say it will be a good practice to add them as they will help keep the voltage constant

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user

Yes thanks for the reply.

Have managed to build the circuit and it is working using a variable supply voltage. Yet to test with battery source though.

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steveastrouk (author)2013-03-11

No, a voltage divider is a very bad idea. You need to use a regulator to drop the voltage. A voltage divider ONLY gives the expected division on no load !

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KJ4ZVQ (author)2013-03-11

In regards to a voltage divider, it will work, as long as the battery stays at 3 volts. If the battery dropped to 2 volts, the output would be one volt. The problem with dividers is that the output is directly proportional to the input, in this case, a 2:1 ratio.

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