power suppy step down

[paul60]

I have a power suppy input 120v 0.22a 26va
output 30v 400ma 12va
using my multimeter i get a reading of 37 volts
what i am trying to do is to reduce the voltage to 24 volts.
can anyone tell me how to go about this.
or where i can find a circuit diagram.
thanks paul

 

[(*steve*)]

You need a voltage regulator. If you get a 3 terminal regulator (the simplest to use) then you'll want one that allows an input voltage between 40 and 45 volts (to give some safety margin),

You also might need some more filter capacitors if the existing power supply has insufficient. 470uF 50V would be fine.

Here is a part that would probably suit. It would require a small heatsink.

That page has a datasheet for the device and there are typical circuits for this device. Note that the filter capacitor I mentioned above is additional to those shown on the circuits that are powered from a DC rail.

 

[paul60]

You need a voltage regulator. If you get a 3 terminal regulator (the simplest to use) then you'll want one that allows an input voltage between 40 and 45 volts (to give some safety margin),

You also might need some more filter capacitors if the existing power supply has insufficient. 470uF 50V would be fine.

Here is a part that would probably suit. It would require a small heatsink.

That page has a datasheet for the device and there are typical circuits for this device. Note that the filter capacitor I mentioned above is additional to those shown on the circuits that are powered from a DC rail.

Do you have a circuit for this ? very new to electronics
or where i can find a circuit
thanks paul

 

[(*steve*)]

Do you have a circuit for this ? very new to electronics
or where i can find a circuit

See Figure 10. Add a 470uF 50V (or higher voltage) capacitor in parallel to the 0.33uF one shown.

 

[mav2541015]

You need a voltage regulator. If you get a 3 terminal regulator (the simplest to use) then you'll want one that allows an input voltage between 40 and 45 volts (to give some safety margin),

You also might need some more filter capacitors if the existing power supply has insufficient. 470uF 50V would be fine.

Here is a part that would probably suit. It would require a small heatsink.

That page has a datasheet for the device and there are typical circuits for this device. Note that the filter capacitor I mentioned above is additional to those shown on the circuits that are powered from a DC rail.

you're looking for a 7824 voltage regulator, use heat sink compound and a heatsink! that is the right part by the way.