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Forum Index : Electronics : MCP1703 Vout

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OA47

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Joined: 11/04/2012
Location: Australia
Posts: 982
Posted: 07:36am 15 May 2018
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I have some PCB's that are using MCP1703/500 regulators that are supplying 5.0 volts and I would like to know if it is possible to raise the regulated output with either external resistors or a diode in the ground connection?
OA47
 
Grogster

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Joined: 31/12/2012
Location: New Zealand
Posts: 9603
Posted: 09:46am 15 May 2018
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Datasheet for MCP1703 does not mention anything like this. My guess is that you PROBABLY can, but if I were you, I would be sending an email to Microchip asking the same question. Their technical gurus would know for sure.
Smoke makes things work. When the smoke gets out, it stops!
 
noneyabussiness
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Joined: 31/07/2017
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Posts: 526
Posted: 05:46pm 15 May 2018
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Same concept would be for the humble 7805... i guess... the values of the resistors may need tweeking... and it can ONLY adjust to a higher voltage.. the centre pin is the ground connection, so you would do the same with the MCP1703.


Edited by noneyabussiness 2018-05-17
I think it works !!
 
Grogster

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Posted: 11:34pm 15 May 2018
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Yes, I agree - PROBABLY. The reason for my saying 'probably' is that we don't have an internal schematic for the 1703 regulator, but it is most likely just a variation of the old analogue ones with lower quiescent current and drop-out voltage etc. I would still recommend that you ask Microchip in an email, then you could be sure.

Raising the 1703's ground-reference point might work fine, then again, it might make the regulator unstable. We KNOW we can do this with the 78xx/79xx regulators, as they describe how to do it in the datasheet.
Smoke makes things work. When the smoke gets out, it stops!
 
noneyabussiness
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Joined: 31/07/2017
Location: Australia
Posts: 526
Posted: 12:52am 16 May 2018
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True... why i said " i guess " .. looking at the block diagram i can't see why not.. but i agree asking the manufacturer is always best practice
I think it works !!
 
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