The following is a split power supply circuit with an instant current limit built in.  This current limited supply protects the amplifier's output transistors from output shorts and current surges during power on.  This design utlities scable current sensing resistors.  You can choose the current limit that is right for you output transistors.

7 Amp limit use 0.1 ohm
  10 Amp limit use 0.068 ohm




Current limit circuit operation is as follows.  Current flow throug R17 creates a voltage, when this voltage reaches 0.7v Q12 turns on and turns off Q10.  When Q10 is off voltage develops across Q10 and this voltage is used to drive the OL (overload) LED1. 



This power supply is suitable for the 150 Watt Power Amplifier Circuit Board.










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