Possible to use -7805- LD 2981 for USB charging?

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Rufusbduck
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Possible to use -7805- LD 2981 for USB charging?

Thinking of making a P60 drop in for a 2× 18xxx host with a USB port and one or more stacked (maybe even a single mode board) LD2981 voltage regulators to use as a portable USB charger. The chips are sot-89 packages with 100mA max output and have the same I/O/G pins as a 7135. Work/won’t work?

Three Tanna leaves to give him life, nine to give him movement. But what if he eats the whole bag?

Scott

Edited by: Rufusbduck on 02/12/2014 - 15:58
texaspyro
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Most voltage regulators don’t like to have their outputs paralleled…

Rufusbduck
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:_( so 100 mA max. Could you explain why or is it over my play grade?

Three Tanna leaves to give him life, nine to give him movement. But what if he eats the whole bag?

Scott

Werner
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Have you searched ebay for step up/down modules, there are a a lot different ones out there

rhd
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In many cases, you can buy entire step down switching circuits on ebay for less than the cost of just the ICs they run on from someone like Mouser or Digikey.

Rufusbduck
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I have some of the regulators and thought I might be able to use a few this way. Any of those step down modules fit in a p60 head w/room for a USB port?

Three Tanna leaves to give him life, nine to give him movement. But what if he eats the whole bag?

Scott

rhd
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Rufusbduck wrote:
I have some of the regulators and thought I might be able to use a few this way. Any of those step down modules fit in a p60 head w/room for a USB port?

Probably, there are a ton. Many shapes and sizes. Many will have USB ports right on the circuit board for exactly this purpose.