Regulator Power Supply 12V 20A Regulator Power Supply 12V 20A

Ini adalah Rangkaian Power Supply. Adaftor ini memiliki Output 12 Volt dan kemampuan arusnya adalah 20 Amper. Rangkaian Regulator Power Suplai ini biasanya digunakan untuk Rangkaian yang membutuhkan arus besar misalnya untuk pemancar radio, atau untuk Power Amplifier yang dayanya besar dan lain lain. Untuk pemakaian arus besar tentunya transistor daya dalam hal ini MJ 2955 membutuhkan pendinginan yang cukup baik tentunya dengan Heatsink yang cukup besar dan bersirip dan sebaiknya pula memakai kipas pendingin agar transistor dayanya tidak cepat rusak. Anda bisa coba rangkaian kipas pendingin otomatis yang telah saya posting sebelumnya.

Berikut adalah skema rangkaiannya

Source : http://circuitdiagram-schematic.com/222/12v20a-regulator-power-supply/

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Soft Start For Switching Power Supply Soft Start For Switching Power Supply

extremecircuits.net
Switching power supply whose output voltage is appreciably lower than its input voltage has an interesting property: the current drawn by it is smaller than its output current. However, the input power (UI) is, of course, greater than the output power. There is another aspect that needs to be watched: when the input voltage at switch-on is too low, the regulator will tend to draw the full current. When the supply cannot cope with this, it fails or the fuse blows. It is, therefore, advisable to disable the regulator at switch-on (via the on/off input). until the relevant capacitor has been charged. When the regulator then starts to draw current, the charging current has already dropped to a level which does not overload the voltage source.

Circuit diagram:

Soft Start Circuit For Switching Power Supply

The circuit in the diagram provides an output voltage of 5 V and is supplied by a 24 V source. The regulator need not be disabled until the capacitor is fully charged: when the potential across the capacitor has reached a level of half or more of the input voltage, all is well. This is why the zener diode in the diagram is rated at 15 V. Many regulators produced by National Semiconductor have an integral on/off switch, and this is used in the present circuit. The input is intended for TTL signals, and usually consists of a transistor whose base is accessible externally. This means that a higher switching voltage may be applied via a series resistor: the value of this in the present circuit is 22 kΩ. When the voltage across the capacitor reaches a level of about 17 V, transistor T1 comes on, whereupon the regulator is enabled.
Source: National Semiconductors

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1.5 - 35 Volt DC Regulated Power Supply 1.5 - 35 Volt DC Regulated Power Supply

extremecircuits.net
Here is the circuit diagram of regulated power supply. It is a small power supply that provides a regulated voltage, adjustable between 1.5 and 35 volts at 1 ampere. This circuit is ready to use, you just need to add a suitable transformer. This circuit is thermal overload protected because the current limiter and thermal overload protection are included in the IC.

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Picture of the circuit:

1A Regulated Power Supply Circuit Schematic

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Circuit diagram:

1A Regulated Power Supply Circuit Diagram

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Transformer selection chart:

Transformer selection Guide-Table For Power Supply

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Parts:

IC = LM317
P1 = 4.7K
R1 = 120R
C1 = 100nF - 63V
C2 = 1uF - 35V
C3 = 10uF - 35V
C4 = 2200uF - 35V
D1-D4 = 1N4007

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Features:

• Just add a suitable transformer (see table)
• Great to power your projects and save money on batteries
• Suitable as an adjustable power supply for experiments
• Control DC motors, low voltage light bulbs, …

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Specifications :

• Preset any voltage between 1.5 and 35V
• Very low ripple (80dB rejection)
• Short-circuit, thermal and overload protection
• Max input voltage : 28VAC or 40VDC
• Max dissipation : 15W (with heatsink)
• Dimensions : 52x52mm (2.1” x 2.1”)

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Technical Specifications

• Input Voltage = 40Vdc max Transformer
• Output Voltage = 1.5V to 35Vdc
• Output Current = 1.5 Amps max.
• Power Dissipation = 15W max (cooled)

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Note:

• It has not to be cooled if used for small powers. 28 Volt AC max is allowed for the input voltage.

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Regulator 5A model Matahari Regulator 5A model Matahari

Skema Rangkaian Regulator 5Ampere ini mempunyai tegangan pengeluaran yang bervariasi dari mulai 3 Volt sampai 13.8 Volt yang di atur tegangannya oleh saklar rotari. Regulator ini sangat cocok untuk berbagai rangkaian, karena pengeluarannya sangat stabil dan tegangannya murni.

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Power Supplay 12 Volt Non Trafo Power Supplay 12 Volt Non Trafo

 This circuit will supply up to about 20ma at 12 volts. It uses capacitive reactance instead of resistance; and it doesn’t generate very much heat.The circuit draws about 30ma AC. Always use a fuse and/or a fusible resistor to be on the safe side. The values given are only a guide. There should be more than enough power available for timers, light operated switches, temperature controllers etc,
provided that you use an optical isolator as your circuit’s output device. (E.g. MOC 3010/3020) If a relay is unavoidable, use one with a mains voltage coil and switch the coil using the optical isolator.C1 should be of the ’suppressor type’; made to be connected directly across the incoming Mains Supply. They are generally covered with the logos of several different Safety Standards Authorities. If you need more current, use a larger value capacitor; or put two in parallel; but be careful of what you are doing to the Watts. The low voltage ‘AC’ is supplied by ZD1 and ZD2. The bridge rectifier can be any of the small ‘Round’, ‘In-line’, or ‘DIL’ types; or you could use four separate diodes. If you want to, you can replace R2 and ZD3 with a 78 Series regulator. The full sized ones will work; but if space is tight, there are some small 100ma versions available in TO 92 type cases. They look like a BC 547. It is also worth noting that many small circuits will work with an unregulated supply. You can, of course, alter any or all of the Zenner diodes in order to produce a different output voltage. As for the mains voltage, the suggestion regarding the 110v version is just that, a suggestion. I haven’t built it, so be prepared to experiment a little.

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UPS POWER SUPPLY CIRCUIT UPS POWER SUPPLY CIRCUIT

This circuit can be adapted for other regulated and unregulated voltages by using different regulators and batteries. For a 15 Volt regulated supply use two 12 Volt batteries in series and a 7815 regulator. There is a lot of flexibility in this circuit.
TR1 has a primary matched to the local electrical supply which is 240 Volts in the UK. The secondary winding should be rated at least 12 Volts at 2 amp, but can be higher, for example 15 Volts. FS1 is a slow blow type and protects against short circuits on the output, or indeed a faulty cell in a rechargeable battery. LED 1 will light ONLY when the electricity supply is present, with a power failure the LED will go out and output voltage is maintained by the battery. The circuit below simulates a working circuit with mains power applied:
Between terminals VP1 and VP3 the nominal unregulated supply is available and a 5 Volt regulated supply between VP1 and VP2. Resistor R1 and D1 are the charging path for battery B1. D1 and D3 prevent LED1 being illuminated under power fail conditions. The battery is designed to be trickle charged, charging current defined as :
-(VP5 – 0.6 ) / R1
where VP5 is the unregulated DC power supply voltage. D2 must be included in the circuit, without D2 the battery would charge from the full supply voltage without current limit, which would cause damage and overheating of some rechargeable batteries. An electrical power outage is simulated below:

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Stabilised Power Supply with Current Limiting Stabilised Power Supply with Current Limiting

A simple bench PSU capable of :-
Approx. 5v to 15v output at 1A
Current limited from about 500mA to 1A (adjustable)

Circuit Operation:
An error amplifier is formed from Tr1 and Tr2, wired as a differential amplifier (often called a long-tailed pair -- look at those collector leads). One input of this diff. amp is taken from the zener diode which provides a stable 4.7 volts, the other diff. amp input is a fraction of the output. Any difference between the two will cause the current through R3 to alter and so will alter the voltage across it and hence to the base of Tr3.

Tr3 and Tr4 are connected as a darlington pair, this produces a very high gain to aid stability of regulation. This darlington pair can be visualised as a single transistor connected in an 'emitter-follower' configuration, the emitter voltage will follow the base voltage (less the 1.2v required to forward bias the two base-emitter junctions), but with a much greater current capacity.
Current limiting is provided by Tr5 which will be forward biassed by a fraction of the voltage drop across the current sensing resistor, R5, set by Vr1. As the current through R5 increases so does the voltage dropped across it, this begins to bias Tr5 on and in so doing causes Tr3/Tr4 to be deprived of base current and so reduces the output voltage.

Tr4 needs a heatsink of at least 10 degrees C/Watt (10C / W) and R5 is expected to carry (1A * 4R) = 4 Watts, so it will need to be a 5W device or four 1R 1W devices in series, mount them on a peice of metal as they will get hot!
The transformer needs to be selected to suit your local mains voltage and provide between 15 v and 20 v out at 1A (thats 15 or 20VA, respectively).

As there is no current measurement built in to the unit, a useable scale could be marked around the potentiometer Vr1's knob such that a known current could be chosen in advance of connecting a load. To do this, connect an ammeter directly across the power supplie's output - this will instantly overload the supply and cause the current limiting to operate. Adjust Vr1 so that the ammeter displays 500mA and mark the knob's position. Repeat the procedure for 600mA, etc. ## DON'T keep the supply shorted for too long as Tr4 and R5 will soon get hot! ##

Bits List...
R1, R2 1k0
R3 2k2
R4, R7 470R
R5 4R 5W (see text)
R6 47R
Vr1 100R
Vr2 1k0
C1 6800uF 25v (4700uF will probably do)
C2 0u47
D1, D2, D3, D4 1N4001 (or a 1 amp bridge rectifier)
Z1 BZY88C 4V7
Tr1, Tr2, Tr3, Tr5 BC108 (or BC109)
Tr4 BD131
Transformer 110/240v to 15 or 20v, 1A

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