Voltage regulator output error

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KhaledOsmani

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Hi

I am using 7805 as voltage regulator
I had connected 100uf at input and 10uf at output

The output voltage is of 6V
Why?
I tried to make a voltage divider at the 6v terminal by branching 10 kohm with two 1 kohm

Not working
 

what is the input voltage?

The 78xx series needs at least a Vin of 2V+xx. For example, the 7805 needs at least 7V in before it regulates

If the Vout - Vin is small [<2V] use a LDO regulator.

- - - Updated - - -

See Disadvantages under http://en.wikipedia.org/wiki/78xx
 

Hi,

Usually 7805 are uncritical.
Try to use an additional load, maybe 10k.

Use 100nF additional ceramic capacitors at both input and output.

Give additional informations like circuit, picture, input voltage...

Klaus
 

sometimes,the LDO need an additional min load in order to fix the ouput voltage
 

The 7805 data sheet specs the output voltage from 5mA to 1A, implying that the minimum output current should be 5mA.
This can be provided by an added 1kΩ resistor from the output to common.
 

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