Adjustable Power Supply 1.25v to 57V, 6 Amps using TIP36C +
LM317HV
The LM317HV
is an adjustable 3-terminal positive voltage regulator capable of
supplying 1.5 A or more currents over a 1.25V to 57V
output voltage range. It requires only two external resistors to set the
output voltage. The LM317HV
is packaged in standard transistor packages that are easily mounted and
handled.
However, the LM317HV supports high voltage, but the current is still
low, only 1.5A, our circuit, we are increasing a drive circuit to
increase the current we need to 6 Amps, with three
TIP36C transistors, which provides an adjustable output voltage between
1.25v to 57 volts, with a current of 6 Amps, which is enough
for a bench power supply.
The schematic electrical diagram, which follows in
Figure 2 below, it's very simple, first one, we have the
voltage input that comes through connector J1, which enters through
resistor R1, that as long as there is no current greater than the one
calculated, there is no drop of voltage in R1, more if the current
increases, there will be a voltage drop of approximately 0.6V, which
will cause the transistors to saturate, causing the current to pass
through the power transistors.
The capacitor C1 has the objective of attenuating the interference of
the ripples and their stability. Capacitor C2 has the function of
eliminating high interference, and capacitor C3 has the function of
constancy to decrease the ripple and stability of the power
supply.
P1, is a 5K analog potentiometer, if you don’t have 5K you can put 4.7K,
which is more commercial, the diodes D1 and D2 are to avoid reverse
voltage over the Integrated Circuit U1, and in the transistors, resistors
R3, R4 and R5, are impact resistors, which attenuate the difference
between the transistors and prevent one from working more than the other.
Fig. 2- Adjustable Power Supply Schematic LM317HV + TIP36
Components list
U1…………….... LM317HV – Integrated circuit, voltage regulator
Others ............… Printed Circuit Board, tin, wire, etc.
PCB - Printed Circuit Board
We are offering to Download the link with the printed circuit board printing files, they
are; Gerber, PDF layout, PNG, all the files with a direct link to Mega.
Hi @Myron 1. Yes you can, just remembering that the TIP36C is 100V, 25A, 125W and the 2SB817 is 160V, 12A, 100W. 2. In this circuit, there is no overcurrent or short circuit protection. My regards!
Hi, I came up again to your circuit and I wonder if D1 in parallel with R6 is correct. I believe that in any polarity scenario, the roles of those 2 components are contradictory. Is there any chance they should be connected in series? Regards!
Hello @Makis Thanks for the message. The function of the resistor is to bring feedback to the ADJ of the Voltage Regulator, together with P1, forming a voltage divider. The function of diode D1 is only to protect the Regulator from reverse currents. If you remove it, nothing happens, it continues to work perfectly. Both it and diode D2, which have the same function. Best regards.
Thank you so much for sharing this design. I have 2 questions:
ReplyDelete1. Can you advise if I can replace the TIP36C transistors with 2SB817 to the design above?
2, Is there a design of the above to limit max current as well?
Kind regards! Myron
Hi @Myron
Delete1. Yes you can, just remembering that the TIP36C is 100V, 25A, 125W and the 2SB817 is 160V, 12A, 100W.
2. In this circuit, there is no overcurrent or short circuit protection.
My regards!
Hi, I came up again to your circuit and I wonder if D1 in parallel with R6 is correct. I believe that in any polarity scenario, the roles of those 2 components are contradictory. Is there any chance they should be connected in series? Regards!
ReplyDeleteHello @Makis
DeleteThanks for the message.
The function of the resistor is to bring feedback to the ADJ of the Voltage Regulator, together with P1, forming a voltage divider.
The function of diode D1 is only to protect the Regulator from reverse currents. If you remove it, nothing happens, it continues to work perfectly. Both it and diode D2, which have the same function.
Best regards.