Sunday, March 18, 2012

Power Amplifier with TDA2050

This is not an ordinary project, but an attempt to make a PCB that is suitable for TDA2050 and LM1875 and has all the necessary circuitry on board - power supply, speaker protection,  delayed turn-on and fast turn-off. This is achieved using the convenient uPC1237 IC.

TDA2050 and LM1875 are pin to pin compatible, the differences in their schematics are the values of a couple resistors and one capacitor. All this allows to make an universal circuit board, suitable for any of these two ICs.

PCB with reversed inscription :)

Later there will be a link for downloading project files.

Update: April 6, 2012

The amplifier is ready. Here some more pictures:

And here is the link for downloading project files: TDA2050.rar
Use it on your responsibility.


  1. plz tell me what is the output watt

    1. It is 2x30W, but it depend of the power supply voltage and the impedance of the speakers connected to the output. Read the datasheets of the IC's - you will find tons of useful info there.

  2. can u send the part list of this project

  3. Hello!!!! Sir, Greetings. :D Can you please provide the components list of this project? I am going to make this project.

    1. Here
      Part Value Package

      B1 KBU8M FBU4
      C1 100nF C050-024X044
      C2 100nF C050-024X044
      C3 1000uF E5-10,5
      C4 1000uF E5-10,5
      C6 2.2uF C050-075X075
      C7 220nF C050-030X075
      C8 22uF E3,5-8
      C9 100nF C050-024X044
      C10 100nF C050-024X044
      C11 1000uF E5-10,5
      C12 1000uF E5-10,5
      C13 4.7uF E2,5-6
      C14 2.2uF C050-075X075
      C15 220nF C050-030X075
      C16 22uF E3,5-8
      C17 4700uF E7,5-18
      C18 4700uF E7,5-18
      C19 47uF E2,5-7
      C20 22uF E3,5-8
      C21 22nF C050-025X075
      D5 1N4148 DO35-7
      D6 1N4004 DO41-10
      D7 BZX85C12V DO41Z10
      H1 MOUNT-PAD-ROUND3.0 3,0-PAD
      IC1 LM1875 T05D
      IC2 LM1875 T05D
      IC3 UPC1237 SOP8
      IN 6410-02
      IN1 6410-02
      J1 OUT1 AC2
      J2 OUT2 AC2
      J3 AC AC3
      JP1 JP1
      K1 G2R2 G2R2
      LED 6410-02
      LED2 LED5MM
      LED3 6410-02
      R1 1k 0207/2V
      R2 20k 0207/12
      R3 22k 0207/7
      R4 1M 0207/7
      R5 1R 0414V
      R6 1k 0207/2V
      R7 20k 0207/12
      R8 22k 0207/7
      R9 1M 0207/7
      R10 1R 0414V
      R11 2k2 0207/7
      R12 120k 0207/7
      R13 120k 0207/10
      R14 56k 0207/7
      R15 9k1 0207/7
      R16 10k 0207/7
      R17 92k 0207/10
      R18 330R 0207/10
      R19 68k 0207/7
      R20 3k9 0207/10
      R21 10k 0207/7
      T2 MPSA42 TO92-EBC

  4. Nice toroidal transformer? Where did you get it from?

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  7. Привет, не могу скачать печатную плату, ссылка не работает, пришлите пожалуйста на

    Hi, I can not download the printed circuit board, the link does not work, please send me at

  8. Здравейте,искам да ви помоля за изходния файл на проекта ви с ТДА2050,необходим ми е за лично ползване и експерименти.Ще ми отнеме много време да го чертая от начало.Благодаря.

  9. Replies
    1. The uPC1237 have two modes of work - "automatic reset" and "latching". If the protection is activated and the mode is "latching" then to reset the circuit you must switch off the power supply. With the jumper you can select which mode you like to use. Open jumper for "latching" and close jumper for "automatic reset". I think "latching" mode is better, because in the event of major fault, with "automatic reset" the relay will keep switching on and off and that is not good.