Hi there. I have a Pioneer ddj sx3 dj controller. Its rated at 5V 3A.
I've trying to build a regulated linear power supply with Lm317 and MJ2955. my p/s works stable at 5.15vDC but when i drawn about 2.8A from the controller (not dummy load), heating is too much, about 70 celcius on heatsink and about 85 celcius at bridge rectifier after 20 minutes in demo mode (leds / jog screens active). I'm using heatsink from old sony power amp rated at 30w rms /ch without force cooling (fans)
Lm317 and 2955 are closer each other.
Ive try output chokes, zobels without good results about heat.
so my p/s are a classic trafo 230vAC to 11.5vAC 4A. bridge rectifier 35A (metallic), 4x10000uF/16v caps in parallel after bridge rectifierlm317+2955 etc....
i'm think controller's internal buck, step up, step down converters oscillates at higher frequencies and the 50HZ p/s can't handle that.
What can i do? can go to LM2576T or LM2596-5.0 or something another switching regulator?
Or the power dissipation is too high so i need smaller voltage trafo?
if change Rb with lower value, 2955 getting hot faster from Lm317 and i dont that….
Thanks in advance.
I've trying to build a regulated linear power supply with Lm317 and MJ2955. my p/s works stable at 5.15vDC but when i drawn about 2.8A from the controller (not dummy load), heating is too much, about 70 celcius on heatsink and about 85 celcius at bridge rectifier after 20 minutes in demo mode (leds / jog screens active). I'm using heatsink from old sony power amp rated at 30w rms /ch without force cooling (fans)
Lm317 and 2955 are closer each other.
Ive try output chokes, zobels without good results about heat.
so my p/s are a classic trafo 230vAC to 11.5vAC 4A. bridge rectifier 35A (metallic), 4x10000uF/16v caps in parallel after bridge rectifierlm317+2955 etc....
i'm think controller's internal buck, step up, step down converters oscillates at higher frequencies and the 50HZ p/s can't handle that.
What can i do? can go to LM2576T or LM2596-5.0 or something another switching regulator?
Or the power dissipation is too high so i need smaller voltage trafo?
if change Rb with lower value, 2955 getting hot faster from Lm317 and i dont that….
Thanks in advance.
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