STK4231II 2 channel 100w stereo audio amplifier circuit

If you want to create the 100 watt OCL audio amplifier circuit. I want you to consider this circuit as one. It uses STK4231 IC products to create a simple, small and best economical.

How it works
The STK4231 is Hybrid IC of Sanyo, in the family of STK4201II. Can provide a high power output to 100 watts per channel. And When connected to the bridge adapter with output altitude of about 400 watts is incredible.
-Built-in muting circuit to cut off various kinds of pop noise.
Greatly reduced heat sink-due to case temperature 125 degrees Celsius.
-Excellent cost performance.
As this circuit, we can design the OCL amplifier 100 watts each channel. Will see that, this circuit consists of only a few external components.
-The capacitor C9,C10 is used to reduce noise at high frequencies.
-The input coupling capacitor are Bolt C1,C11.
The C2,C12 is defined low frequency cut off point that Which can be calculated from the formula :

F=1/6.28 C2xR5


Note: two capacitor C2,C12 is defined gain ratio at low frequency but will be must over high Because, while open this circuit will be has a noise “thub…b.b.b” out to your speaker.

– The boost trapping capacitor are C3 and C13. If the value is too low, resulting distortion increases torque at low frequency.

– To reduce oscillation by C5, C8. which reduces the impedance of the power supply circuit to suit the use of IC.
Setting gain ratio of circuit, which is defined by R5 = 560 and R4=56K will be total gain is VG = 40dB.
If you want to change the rate of expansion, it should change the R5.
The idle current is defied by R21,R22.

Hey! Oh… Is it too large circuit for you, Right?

Look below: You may like it.

TDA2030 Stereo Amplifier with PCB



Caution! This project needs to use the speaker protection circuit. Otherwise, your speaker may be damaged.

The power supply circuit
This our circuit use dual voltage positive – negative 50 volt and current is 5 Amp, we so use power supply as this figure which.
How to build.
It’s very easy to create, even if you are a beginner. It is important to place the devices correctly follow circuit diagram.
In this figure is PCB and putting position the parts. The IC shouls be hold with the big heat sink.

Other circuits are recommended

  1. More Audio Amplifiers with PCB

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I always try to make Electronics Learning Easy.

This Post Has 40 Comments

  1. Please share me the PCB Circuit layout for the STK4321 MK 2 as i will love to try the Making of PCB STK4321 MK2 ..

    Rakesh Sharma
    Call + 91 9762089423.

  2. in this circuit how to use 5.1 hometheater used,with stk4231 ic and 8 inch subwoober,and with 100 watts only other speaker or how to use wstts.

  3. STK4231 original ic how much price?

  4. Hi,Bala
    I am sorry,I don’t know its prices now.


  5. stk 4231 ic
    avialable in kerala?

  6. 350/TK in Bangladesh

  7. Hi,Mehedi
    Thank your feedback.
    Or you can look for it in

  8. hai friends iam raju from yuvaraj bisnes stk amplifiers i want stk 4231-11 components pcb boards please any infarmation

  9. Dear,for assembling STK-4231-11,can i use the same pcb configuration used forSTK4141-11?Because i had a stk 4141 circuit working with 30V/5Amps Dc Dual supply,that ic got may be replaced.STK 4231,is it available at kolkatta market?

  10. Where availabel at mumbai stk 4231II ic and all type high waatt ics please give me address my self prashant

  11. this ic (stk4231II) IS 200000 rials in iran.
    thanks for your great circuit.

  12. Hi Mohammad,
    Thanks for your feedback.
    It is old IC that good sound for me.

  13. very nice i want to one 1000 watts power amp board good sound your me.

  14. where can i get panasonic sa-vk800 multi amp system STK 470-090 IC

  15. hi. why pin 16 is connected to -50v in pcb and top silk but in schematic pin 16 of stk isn’t connected to -50v? and another question that why do you use 100uF capacitor except 10uF(C7) in top silk?please help.

  16. please suggest any 5.1 audio for 100watts

  17. Hi momename
    please help me faster.I bought it’s components and I dont know
    what to do?I need your help.

  18. Hi momename
    i made this circuit according to the top silk
    that you had put in this part for stk.
    now I want to say if others want to make this circuit;
    please follow the top silk information.
    when i wanted to start this circuit;suddenly I SHOCKED
    make this circuit and enjoy of it. thank you very much momename for your great amplifier circuit.

  19. where shall i get 4231 ic build amplifiers in chennai market or inside tamilnadu

  20. Should pin 16 shouldnbe connected or left opened….?
    And i am following the schematic diagram i.e. the first is it correct?

  21. is stk 4321 mk II available in kolkata

  22. I made the circuit but its not working…i tried with schematic , top silk and the bottom layer but the resistor R10 is getting burnt and the ic is getting heated…please help as soon as possible…!

  23. The value specified for R10 is 1 killo ohms i also tried with 10killo ohms…that also is getting burnt…please help

  24. hi sir, can u pl arrange pcb

  25. how many current in stk4231 audio amplifier max.

  26. STK 4231 redi avelebal he to context mi hame chahiye holsel my cnntect no 09427388905

  27. you will get all stk ics at

  28. Bangladash market price only $3.00. Thanks.

  29. Sir i am desired used this ic to subwoofer for 5.1 system pls said transformer rating alsow which ic used to other 5 channel for 5.1 system

  30. sir gud pm

    value of resistors is it 1/4 watt or 1/8 watt and for capacitors how many volts do i use

    tnx and god bless

  31. hello,

    what is the speakers specs?
    the input in voltage is 50+ 50- , but what is the input in Amps?

  32. What is the size or watts of R3,R13,R7,17?

  33. how many 8″ speakers may connected in stk 4141

  34. what abt no.8 pin (Mute)….? how to open this point…by giving +5V supply or not..???

  35. now i want to adjust bass, volume but i don’t know how to do that , Could you recommend me?

  36. I want to make a 50+50W amplifire please give me a link there is details

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