50W MOSFET Amplifier circuit OCL using K1058 + J162

The 50w MOSFET amplifier circuit  OCL (K1058 + J162) is easy to build, and very inexpensive.

To use Power Supply +35V -35V at 2A. Power Mosfet (K1058 + J162) must be mounted on heatsink.

We can directly connect it to CD players, tuners and tape recorders.

If you want a good amplifier, at affordable prices, for you to enjoy at home.

I recommend this circuit, which has excellent sound quality, is not lose its sound expensive.

How it works

In the circuit can be seen. Similar to a general audio amplifier MOSFET, Except for the output power MOSFET, instead we use J49 and K134, which are more expensive than necessary.

We use dual output number J162/K1058, which Cheap much more. And other features. Not less than any.

Power Amplifier OCL 50W by Mosfet (K1058 + J162)

Circuit diagram of 50W Power Amplifier OCL Mosfet (K1058 + J162)

Features of the circuit

  • Power output at 1kHz
  • Load 8 ohm 50W
  • Load 4 ohm 88W
  • Power bandwidth +/- 1dB 20-50,000Hz
  • Frequency response +/- 1dB 20-50,000Hz
  • THD 20Hz-20kHz UP to rate power 0.05%
  • Slew rate 20V/ microSec.
  • Damping factor better than 50
  • Signal to noise ratio 88dB.
  • Input voltage for maximum 100mV.

Also, the results from this circuit, it is the high-frequency response to better output with J49/K134.

The operation of the circuit

The input signal is entered to C1 pass through a low pass filter circuit. With R2, C2 to the differential input circuit Q1(MPSA93), Q2(MPSA93) to Q4(MPSA43), Q5(MPSA43) that an act to amplifier an input signal to Input signal to be strong enough to drive the gate of the output MOSFET. (Q8, Q9)

The diode (1N4148) D2, D3, D4, D5 It is a protection circuit to drive the gate of the MOSFET is too strong. May cause damage to the power MOSFET.

Recommended: High MOSFET Power Amplifier

The Q6(BC546), Q7(BC556), It controls the voltage supplied to the driver. not change follow the swing of the power supply, while we turn on the high power.

And prevent noise that feedback to from the power supply wires, thus reducing the noise of the circuit as well.

How to build

This circuit is very easy to make because it is designed in the PCB module. To reduce oscillators from the wire at legs MOSFET too long.

Therefore, every piece of equipment. Including the power MOSFET and the heatsink.

So, it is designed to be installed on the PCB, as shown in Fig.

In creating, So just devices connected to form correct, careful soldering point to the closest point of successful, and not Short to well.

PCB of Power Amplifier OCL 50W by Mosfet (K1058 + J162)

PCB 50W Power Amplifie OCL Mosfet (K1058 + J162)

– Check the output MOSFET that insert the mica insulation is good enough or is not. Using Ohmmeter measurement, make sure not to well short circuit or Short to the heat sink is available.

When examining all done, until sure is good to successfully. So trial connected to the voltage of the power supply, to the circuit to work right away.

Source: Pk Kit circuit

Note :

This project has a PCB amplifier is ready to build. You can view other projects.
Click here : Audio Amplifier(with PCB)

Note: If you think that This power amplifier circuit is not good enough. For your work. It is hard to find parts. You do not have it now. These circuits may be viewed below. It may be appropriate for you.


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This Post Has 6 Comments

  1. I have a question.
    In circuit is shown that 10ohm resistor is paralel with coil and another 10 ohm resistor comes from C13 but on pcb is not like that?
    In circuit are also 473 capacitors, on the pcb are 104.
    And there is no data for L1.
    Can you please explain.

    1. excuse me mister Maksmilijan, have you ever figured out the value of the L1 in the schematic diagram? thank you!

  2. Hi,
    I have a question:
    I want to use separate power supply for each channel.So the transformer must be 2 x 24 /2A.
    That is write?


  3. what is the disadvantage of setting quiescent current very low.

  4. excuse me mister Maksmilijan, have you ever figured out the value of the L1 in the schematic diagram? thank you!

    1. L1 must have 10 turns of 1mm wire in the shape of a pen.

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