Many
circuits are printed by various magazines and Blogs. Here is a
simple homebrew high-current power supply (PSU). The
specialty of this power supply is a very good performance despite minimal use of
components. The
power supply provides 12V output 12A. Here I added at the input
of a noise damping device. RFI
filter and do as "conductor" NO FU1211, Switzerland, or equivalent easily
available in the market. 2N6320
transistor 2N6321 series or T1 is for this circuit (replacing home test, BD249
transistor with a current rating of 25A) was used. This
is a high current, high voltage transistor power dissipation of 300W. Components,
including the 14V zener D2, R2, R3 and T2 (SCR BT151 used in my home for
testing) are the protection circuit lever bypass AC input voltage and fuse F1
if the height of the 14V DC output voltage crosses.
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| Figure. 1: Economical high current power supply unit |
Use of a heat sink with a sufficient capacity is very helpful. Heat from a cooling fan for the transistor T1 However, a smaller heat sink for the regulator IC 7812th the output diode reverse polarity. All components are commercially available. They can have a transformer with 0-20V AC, Number 15A for the secondary circuit. The SCR 18A should be 200V. The Ferrite (FB) of the base and the output terminals in order to avoid interference. Use a 16A, 200V PIV (peak nominal voltage versa) bridge rectifier followed by a nominal 60V 15000μF rectification and filtering capacitor.
You can use this circuit for applications such as HF and VHF stations use moves. If the current request is, say 19-20A, and requires minor changes in the rated current of the transformer and the bridge rectifier, etc. You can also 2N3773 transistor T1 with two (parallel). The noise filter circuit is connected between the input AC 230V and the transformer shown in Figure 2. However, you can also finished ELCOM noise filter for this purpose. This diet is easy to assemble RF immunity and surge / reverse polarity protection.
General
Purpose
This
power supply is an all-purpose room, which is used to operate QRP transceiver
testing RF amplifier and VFO or other general purpose application 2m/70cm how
to easels. No
external components of a diode and two capacitors need. The power supply
is 12 VDC ± 0.25 V at 1.5A max there. The
IC SI-3120CA a hybrid controller is 5-pin, drip. With a kind of maximum input
voltage (VIN) and 35V power dissipation (PD) of 18 watts The
IC has. Several internal protections against over voltage, over current and
thermal shields VIN
specified 13V to 30V. Your factor is 54dB ripple
rejection. No
longer need external protection as leverage. The
use of a heat sink for the integrated circuit is recommended. You can
use a transformer 0-22V AC, 2A secondary number and a 1N4007 diode is diode
protection worship.
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| Figure. 2: General-Purpose power supply unit |
Discrete PSU for QRO
The QRO transceiver circuit
design for PSU (50W) and the linear RF amplifier etc. IC LM396 is a voltage
regulator designed to supply high-voltage output current adjustable from 1.25 V
to 15 V at currents up to 10A Energy consumption (PD) is 70W. To
adjust the output voltage, only two external resistors are required. This
circuit does not depend on external capacitor for frequency stabilization. The
internal structure of the integrated circuit combines high technology with
discrete power transistors monolithic linear IC modern treatment. This
combination results provide a high performance controller single chip 10 amps
of current. Maximum
value of the input voltage is 20 V and ripple rejection is 74dB. The
output voltage is determined by the resistor R1 and R2. VOUT = 1.25 (R1 + R2/R1). Transistor T12
is used to control the current. In
this circuit, the power loss (PD) is limited to the integrated circuit to 50W. Therefore,
we need an external power transistor driver TIP36C transistor is used, and the
power consumption is 90W. A current sense resistor
(R5) used 0.15Ω. If
the current is below 4A, the voltage across R5 is less than 0.6 V, and the
transistor in the off state. Voltage regulator works as before. LM396
maintains a constant output voltage and the load current through LM396. When
the load current is greater than 4A, the voltage across R5 is greater than 0.6
V and the transistor turns on. The
external load transistor used to more additional current of 4A. It
is also a circuit because the transistor provides the current value of the load
current in excess. The current through LM396 is just over 4A. The external
transistor does the rest of the stream. Protection DC
output voltage lever with high added value. LED1 VIN terminal
voltage indicator is normal. When turned off, the VIN
is very low. Capacitor
between ADJ and the ground terminal regulator increases the ripple rejection.
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| Figure. 3: Discrete power supply unit for QRO |
Note Test
Protection
diodes to prevent high value capacitors in the output stage of the controller,
since the discharge of current weaknesses and damage to the controller.