40V 2A LM317 & TIP42 Power Supply

40V 2A LM317 & TIP42 Power Supply


40V 2A LM317 & TIP42 Power Supply


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.

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

Sorry, comments are closed!