How to Make Simple & Powerful Amplifier Power Supply

 

How to Make Simple & Powerful Amplifier Power Supply

Since the components used are all transistors (MOSFETs, diodes), passive (resistor, capacitors and a torroidal coil) you will be basically making a DC-DC converter with push-pull topology to get from an incoming 12 Vdc to AC and again convert it into symmetric dual DC rails. toroidal coil like this increase a lower DC voltage (e.g. 12V) to a higher DC voltage with a center tap, so youget an output of 12-0-12V. Follow these steps below for complete setrup.

Components Overview:

1. IRFZ44N MOSFETs x 2: These function as the switching devices for the primary side of the toroidal coil.

2. 1N4007 Diodes x 2: Diodes are used to save the MOSFETs .

3. Resistors 1k x 2: These help regulate the gate voltage of the MOSFETs.

4. Capacitor 0.3µF/400V: This component is for filtering.

5. Toroidal Coil:

        Primary winding: 8-0-8 turns of SWG 18 copper wire.

        Secondary winding: 22-0-22 turns of SWG 18-27 copper wire (for stepping up the voltage) or depending on your wire turn ( per turn 1/2 volt).

6. DC Input (6-13V): This is the supply voltage for the circuit.

    DC Output (20-0-20V): This is the target output voltage.

Circuit Description:

1. Push-Pull Switching Stage:

The circuit begins with the two IRFZ44N MOSFETs set up in a push-pull arrangement. One MOSFET turns on while the other turns off, alternating in cycles.

 A control circuit drives the MOSFETs, generating alternating switching signals at a high frequency (20 kHz–50 kHz).

 The 1K resistors connect the gate of each MOSFET to the control signal source, limiting current and safeguarding the MOSFETs from excessive gate drive.

2. Toroidal Coil or Transformer:

          The circuit is built around, toroidal Coil or transformer which step-up the voltage of 12V to high levels. The first view.

           Primary winding:  It features the primary winding, 8-0-8 turns connected to the MOSFETs. Because this is essentially telling two MOSFETS on separate legs to turn on, When one MOSFET turns on, it flows current through one half of the primary, in essence creating a magnetic Field.

       Secodery winding: This creates the voltage rise and has 22-0-22 turns as secondary winding. Center tap: 0V (ground reference)Ends : +12V and -12V.

***Circuit Diagram*** 

3. Rectification and filtering:

Because the MOSFETs switch at high frequency the output of this will be an AC voltage, but as the source was a general transformer it is not possible to know for sure if this was built as center tap or just normal single winding transformers.

 That is similar to the full-wave rectification setup you get in two 1N4007 diodes which convert the AC output into DC.

Followed by the same as mains these diodes 2200uf/35v x 2 capacitor is placed before output to smooth the DC voltage, reduce ripple and ensuring a stable output.

4. Output:

The transformer output is approximately 20-0-20V DC (post-rectification and filtering). This is achieved through the step-up transformer and the rectifier circuit.

Circuit Operation:

. Connected to the DC input (6-13V) The control circuit switches the two MOSFETs alternately, forcing the primary side of the toroidal.

. Then the toroidal transformer voltage multiplies and provides an output at while connecting with AC pin of Secondary the we rectify and filter finally get a 12-0-12v dc.

. Actual output voltage can vary depending on input voltage, toroidal winding ratio and load but should generally be in the range 6-13 volts dc at modest input levels (say 12V input).

Final Notes:

. Able heat sinking necessary for MOSFETs, may get warm during heavy operation.

. Toroidal coil windings must be insulated properly to avoid short circuits.

. If output voltage does not fit your needs you can make the toroidal coil turn ratio slightly adjust. This PSU would work fine for low to moderate power amplifier uses!