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7.5v regulator.

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iloveelectronic said:
do i really need to use a heat sink?

Depends entirely on what you are powering with it.

As for being 'chunky' you don't have to use the pot as the website does, you can use a preset.
 
hi ILE,
You can use a 78L05 or equivalent [about 150mA].
Connect a series resistor between the 78L05 Gnd[0v] pin and 0v.

If you have a low value variable resistor, say [1K0] use that, adjust the
resistor to give you +7.5V

You can use a 7805 for higher currents.

Regards
EriG
 
hi eric

cool, cause like few hours ago i build a 5 volt regulator using a 7805. do u have a diagram of a 7.5 v regulator using a 7805?
 
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hi ILE

Try the attached circuit.

If you cannot get the full range, reduce the 1K0 to 470R, ok.

EricG
 
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The 1k resistor needs to be 120R, unless you're happy with having a minimum load of 10mA.
 
7.5 V regulator

If the voltage in your circuit does not have to be exactly 7.5 V. look for an
LM 7808. Some of the larger distributors stock them.
 
Hero999 said:
The 1k resistor needs to be 120R, unless you're happy with having a minimum load of 10mA.
Hero, I think you're referring to an LM317. Eric is using a 7805. 120 ohms would draw about 42mA.
 
correct...both circuits are identical....
only values are adjusted to match chip with different output
 
iloveelectronic said:
hi,

i need a 7.5v regulator, but i can't find any diagram on google, can someone please post a 7.5v regulator in here please? thx :D
Hi

you have not indicated the load current you required?
 
Ron H said:
Hero, I think you're referring to an LM317. Eric is using a 7805. 120 ohms would draw about 42mA.
Thanks, I missed that.:D
 
I don't know if the target is a pc fan like the first circuit but in that case just use +12 to one fan terminal and +5 to the other and you get 7V to the fan. that's a common trick for reducing a fan.
 
Or use a 7808 with a 1N4004 in series with the output which will give you 7.4 Volts.
 
Hi all
LM317 is perhaps the best and you may have one fixed voltage at 7.5 and also usea concealed switch(to prevent accidental switch over,) to go to variable mode and get adjustable supply even. the advantage is it can deliver 1.5 Amps if properly heatsinked.
 
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