Re: gEDA-user: 5v reg 4v out

[al davis <ad106@xxxxxxxxxxxxxxxx>]

On Wednesday 17 May 2006 17:23, Marc Price wrote:
> Is there a quick and easy way to get 4v out using a
> 5v regulator l7805cv
>
> I keep getting 5.04v tried adding a v resistor to the gnd

A resistor across the output will only drop the voltage when you 
draw too much current.  Don't do that.

A resistor in the sense lead can only raise the voltage.


Method 1: Try a diode or two in series with the output.


Method 2: If you have a negative voltage available, use a 
resistor and two diodes to make -1 volt.  Connect the 
regulator's ground terminal there.


The preferred way is to get a LM317, but you asked for a kluge.