Regulated Power Supply 40V 2A by LM317 + TIP42

This is circuit Fix power supply Regulator 40V 2A for main Power Amplifier 30W.
It is use IC LM317T (Hot IC Variable Regulator) and Transistor TIP42 for boost up Current to 2A max . Other detail see in circuit.
A very good and powerful Regulated Power Supply section was implemented by simply adding a PNP power transistor to the excellent LM317T adjustable regulator chip. In this way this circuit was able to deliver much more than the power required to drive two Mini-MosFet amplifiers to full output (at least 2Amp @ 40V into 4 Ohm load) without any appreciable effort.
Regulated Power Supply Parts:
R1_______________3R9 1 or 2W Resistor
R2______________22R 1/4W Resistor
R3_______________6K8 1/4W Resistor
R4_____________220R 1/4W Resistor
R5_______________4K7 1/2W Resistor
C1____________3300µF 50V Electrolytic Capacitor (or 4700µF 50V)
C2,C5__________100nF 63V Polyester Capacitors
C3______________10µF 63V Electrolytic Capacitor
C4_____________220µF 50V Electrolytic Capacitor
D1_____Diode bridge 100V 4A
D2___________1N4002 200V 1A Diode
D3______________LED Any type and color
IC1___________LM317T 3-Terminal Adjustable Regulator
Q1____________TIP42A 60V 6A PNP Transistor
SW2_____________SPST Mains switch
T1_____________230V Primary, 35-36V (Center-tapped) Secondary,
50-75VA Mains transformer (See Notes)
PL1____________Male Mains plug with cord

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The -12 Volt Supply by TIP42

The -12 volt supply, like the +12 volt supply, uses discrete components rather than a 7912 voltage regulator IC. Here, we use a 1N4742A Zener diode, rated at 12 volts, 1 watt, as the main regulating element.
The power supply shown in the above schematic diagram uses a Zener diode as the main regulating device, to maintain a constant output voltage in spite of changes in input voltage. The type 1N4742A diode is rated at 12 volts, with a power dissipation limit of 1 watt. Since we want to be able to deal with load currents of at least 100 mA and possibly more, we cannot use the Zener diode by itself. (Under no-load conditions, the Zener diode would have to handle that 100 mA, which would result in a power dissipation of 1.2 watts. This would overheat and destroy the diode in short order.) Therefore, we add a power transistor as the main current-handling device for the power supply. The TIP42 PNP silicon transistor (available from Radio Shack) is rated to carry up to 10A collector current and a power dissipation of 65 watts.

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Posted in: power supply