18V DC power supply circuit using LM7818

When we need to build an 18V DC power supply circuit. For a transistor pre tone control. It will have a quality sound. If we use a stable DC voltage regulator.

We have many circuits to builds. But now we like the 18V DC power supply circuit using IC-7818. Because it is so well circuit, small size so fast to build, sometimes we can assemble them on a breadboard. And cheap we like it!

18V DC power supply circuit using LM7818

The 18V DC power supply circuit

The IC-7818 or LM7818 or L7818 is a circuit’s key. It is a fixed DC voltage regulator IC that so popular. Since they have a low load regulation so low noise signal on our audio system.

LM7818 pinout

The working principle

As we build this circuit put on the power amplifier. So The output terminal of the transformer is our AC voltage input. The proper AC input range from 18V to 22V.

You may use the 18VAC 1A transformer. It makes an output current of 1A.

Then, the AC voltage passes through a full-wave bridge rectifier (D1 through D4). They will rectify the AC into pulsating DC.

Next, the 1,000uF 35V- capacitor will filter a pulsating DC into the DC unregulated voltage. Which this voltage about 24V to 26V.

If the output current is not full to 1A. You may add one 1000uF 35V capacitor. It can keep more current.

This DC voltage will flow through the input of 3-terminal IC1. It will converter any DC voltage to stable +18 volts regulated.

The 470 uF 35V capacitor filter DC voltage to smooth better.

Now, we have the stable regulator of 18V DC power supply for a lot of application next times.

Although the IC has good circuit protection. We have to use the IC1 with a suitable heatsink because while it is working with the high current it so heats.

Parts list we need it
IC1: LM7818 or L7818_18V voltage regulator
C1: 1000uF 35V_Electrolytic Capacitors
C2: 470uF 35V_Electrolytic Capacitors
D1: D4: 1N4007_1000V 1A Silicon Diode

18V Dual DC Regulator circuit

Some circuit requires 18V dual power supply circuit or 3 terminal output (+18V, – 18V and Ground).

We can use IC7818 and IC7918 to do this power supply.

18V Dual Regulator using 7818 & 7918 Also, see

Also 18V DC power supply Circuits

See more many circuit ideas for you.

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  1. andy cypert

    bilding a wind mill gen get 2vd to 28vdc can i make a unit to get a good stedy rate ov 16vdc up to 10amps no one can see this pasble ???

  2. Jayambika

    I see your 18v power supply circuit. I think you forget about the voltage drop here. coz when u take 18 v AC Transformer it gvs 18 v but what about ic and diode voltage drop and conducting voltage.?pls explain

  3. haiwuxing

    Which software do you use to draw the pretty circuit?

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