sghr220
Junior Member level 3
Hi guys,
I am building a 10A variable voltage (1.25~50V) power supply using lm317 regulator and the NPN 2sc5200 power transistor as a pass transistor. The transformer output is 48VAC and the circuit is a slightly modified version of the datasheet circuit. When i try to simulate the circuit in Proteus (file attached in this post) i get a fluctuation in the output voltage not really sure where it's coming from. Also should i add an emitter resistor to the output transistor? and if so what is the recommended value and rating?
I really appreciate your help and i am sorry if the subject has been beaten to death in other topics but i really can't find definite answers to my questions elsewhere.
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Sorry wrong forum, Could the moderators please move the thread to "Analog Circuit Design" thanks.
I am building a 10A variable voltage (1.25~50V) power supply using lm317 regulator and the NPN 2sc5200 power transistor as a pass transistor. The transformer output is 48VAC and the circuit is a slightly modified version of the datasheet circuit. When i try to simulate the circuit in Proteus (file attached in this post) i get a fluctuation in the output voltage not really sure where it's coming from. Also should i add an emitter resistor to the output transistor? and if so what is the recommended value and rating?
I really appreciate your help and i am sorry if the subject has been beaten to death in other topics but i really can't find definite answers to my questions elsewhere.
- - - Updated - - -
Sorry wrong forum, Could the moderators please move the thread to "Analog Circuit Design" thanks.