Showing posts with label supply. Show all posts

Tuesday, January 6, 2015

Power Supply for regulated current and voltage

Click to enlarge

This is also another useful project for anyone working in electronics.

Both Current and Voltage Regulation is Extremely Important to Help Prevent Damage to Circuit, Especially Experimental Circuits.

This circuit used a Rotary Switch to select Various Current ranges as a Potentiometer is not very practical for the lower resistance/High Current Ranges.

Thursday, December 11, 2014

Adjustable Lab Power Supply

Make your own lab power supply complete with adjustable voltage and constant current source. Using single IC (LM324)

Friday, October 10, 2014

A truly timeless circuit. LM317 is a versatile and highly efficient 1.2-37V voltage regulator that can provide up to 1.5A of current with a large heat sink. Its ideal for just about any application. This was my first workbench power supply and I still use it.

Since LM317 is protected against short-circuit, no fuse is necessary. Thanks to automatic thermal shutdown, it will turn off if heating excessively. All in all, a very powerful (and affordable!) package, indeed.

Although LM317 is capable of delivering up to 37V, the circuit pictured here is limited to 25V for the sake of safety and simplicity. Any higher output voltage would require additional components and a larger heat sink.

Make sure that the input voltage is at least a couple of Volts higher than the desired output. Its ok to use a trimmer if youre building a fixed-voltage supply.

Problems:

Follow all the safety precautions when working with mains voltage. Insulate all connections on the transformer.

Possible uses:

Variable workbench power supply, fixed-voltage supply... Just about any possible application when no more than 1.5A is necessary.

read more at: http://english.cxem.net/power/power8.php

Tuesday, September 23, 2014

Switching Power Supply 13 8V 40A

This power supply circuit produces 13.8V regulated to better than 1%, at a continuous load current of up to 40A. It has current limiting, making it appropriate for direct connection to a 12V backup battery. If the current limit potentiometer is turned up, the power supply can deliver up to 60A on an intermittent basis, while maintaining regulation. No minimum load is required. The ripple on the output is about 20mV, and the efficiency is 88%.

More Switching Power Supply

Saturday, September 6, 2014

Digital DC Power supply using PWM with PIC microcontroller

In our lab I saw many DC power supply which have a variable knob to regulate the output. I was dreaming to make such a project where I can regulate the voltage using push button.As I am not an industrial level expert so this project is just about a digital DC power supply of small range(5V-12V). You can press push buttons to increase or decrease output voltage.Here we use LM317 to regulate the output voltage. Output voltage is controlled by the PWM output of a pic microcontroller.An OP-AMP is required to amplify the PWM output level. The idea is simple and easy to implement in schema.

Necessary Software:

1. Proteus 7.8 Professional
2. MicroC Pro
3. PICKIT 2.61 Boot Loader

Necessary Equipment:

1. PIC 16F73
2. LCD 16x2
3. 20 MHz Oscillator
4. Variable resistor (5k Ώ, 1k Ώ, 50k Ώ)
5. 7805 Voltage Regulator
6. 7818 Voltage Regulator
7. LM317T Voltage Regulator
8. LM741 Op Amp
9. Push Button Switch
10. Resistor (1k Ώ, 220Ώ)
11. Capacitor (47, 10, 1, 0.1 uF)
12. Vero board
13. Heat Sink

Methodology:

Figure1: Block Diagram of whole system

Schematic Diagram:

Figure 2: Schematic Diagram of the schema

Description:

· LM317 can give output of 3-37V . It can change its output voltage according to the adjust pin voltage.
· PWM signal is generated from microcontroller. The signal is applied to RC low pass filter which makes a DC voltage level.
· This voltage is applied to Op Amp to get required gain.
· This amplified voltage is applied to LM317 adjust pin.
· From microcontroller we adjust the width of PWM signal. More width gives higher DC level.
· It also changes the adjust pin voltage which controls the output of LM317.

Final Output:

Possible Application:

· Smooth speed control of DC motor

· Valve control of liquid and gas flow.
· Supply for different Electronic Circuit etc.

Downloads:

Download the full project file here.

High current output switching power supply

This is low voltage high-current ouput , switching dc power supplly wiht input 220 Volts AC , In this circuit , an St2 diac relaxation oscilator, Q3 , C1 , and the diac , initiates conduction of the output switching transistor Q1, the on time of which is maintained constant by a separate timing / commutation network consisting of Q2 , C2 ,SUS , and SCR 1. See schmeatic diagram below :

The output voltage , consequently , is independent on the duty cycle . To compensate for unwanted variations of output voltage because of input voltage or load resistance fluctuations , an H11C wired as a liniear - model unilateral pnp transistor in a stable different amplifier configuration is connected into the galvanically isolated negative- feedback loop.

Friday, September 5, 2014

Stable USB Power Supply

A common problem when an AC mains adapter is used to power a USB device is that the voltage does not match the nominal 5 V specified by the USB standard. The schema shown here accepts an input voltage in the range of 4-9 V and converts it into a 6-V output voltage, which is then stabilized to a clean 5-V level by a series regulator. The combined boost/buck converter used here operates on the SEPIC principle. That principle is quite similar to the operating principle of the Cuk converter, but without the disadvantage of a negative output voltage.

Circuit diagram :

Stable USB Power Supply Circuit Diagram

The schema is built around a MAX668, which is intended to be used as a controller for boost converters. The difference between a SEPIC converter and a standard boost (step-up) converter is that the former type has an additional capacitor (in this case C2) and a second inductor (in this case, the secondary winding of transformer L1). If C2 is replaced by a wire bridge and the secondary winding of L1 is left open, the result is a normal boost converter. In that case, a current can always flow from the input to the output via L1 and D1, even when the FET is not driven by IC1. Under these conditions, the output voltage can never be less than the input voltage less the voltage drop across the diode.

The operation of a SEPIC converter can be explained in simple terms by saying that C2 prevents any DC voltage on the input from appearing at the output, so the output voltage can easily be made lower than the input voltage. The second coil causes a defined voltage to be present at the anode of D1. It is also possible to replace the transformer by two separate coils that are not magnetically coupled. However, the efficiency of the schema is somewhat higher if coupled coils are used as shown here. The value of resistor R4 is chosen to limit the maximum current to 500mA, which is also the maximum current that a USB bus can provide according to the specifications. Resistors R1 and R2 cause the voltage across C3 and C7 to be regulated at a value of around 6 V. A low-drop regulator (LM2940) is used to generate a stabilized 5V from the 6V output (with ripple voltage). The efficiency should be somewhere between 60% and 80%

Sourced By: Circuitsstream

Thursday, September 4, 2014

Regulator Power Supply 1A Circuit Schematic

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

This is the Regulator Power Supply 1A Part List :

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

Wednesday, September 3, 2014

Part 2 High Voltage Supply Wiring diagram Schematic

This High-Voltage Supply Circuit Diagram uses a transistor oscillator and a voltage multiplier to charge CIO and CI 1 to a high voltage. When the spark gap breaks down, T2 produces a high-voltage pulse via the capacitance discharge of CIO and Cll into its primary. T2 is an auto ignition coil.

Read : High-Voltage Pulse Supply Circuit Diagram

High-Voltage Supply Circuit Diagram

Power Supply Variable 1 3V 12 2V 1A Circuit

Power supply circuit to generate output below were variations between 1.3V DC to 12.2V DC with 1A current.
In addition, the power supply circuit is also equipped with over-current protection or shield against belebih flow. Power supply circuit is very simple, but the quality is quite good, made her basiskan regulator IC LM723 is a pretty legendary.

Description:

R2 to set the output voltage. The maximum current is determined by R3, over-current protection circuit inside the LM723 to detect the voltage on R3, if it reaches 0.65 V, the voltage output will be off her. So the current through R3 can not exceed 0.65 / R3 although output short-circuit in his.

C3 and C4 are ceramic capacitors, as much as possible directly soldered to the PCB, this is because the LM723 is prone to oscillation that is not cool.

LM723 works with 9.5V input voltage to 40 V DC and the LM723 can generate its own current of 150mA when the output voltage is not more than 6-7V under input voltage.

Specifications:

Output (value estimated):

Vmin = (R4 + R5) / (R5 * 1.3)

Vmax = (7.15 / R5) * (R4 + R5)

Imax = 0.65/R3

Max. Power on R3: 0.42/R3

Min. DC Input Voltage (pin 12 to pin 7): Vmax + 5

Component List:

B1 40V/2.5A

C1 2200uF (3300uF even better)

C2 4.7uF

C3 100nF

C4 1NF

C5 330nF

C6 100uF

Green LED D1

D2 1N4003

F1 0.2A F

F2 2A M

IC1 LM723 (in a DIL14 plastic package)

R1 1k

R2 Pot. 5k

R3 0.56R/2W

R4 3.3k

R5 4.7k

S1 250V/1A

T1 2N3055 on a heatsink 5K / W

TR1 220V/17V/1.5

Tuesday, September 2, 2014

Simple 50V Bench Power Supply

Simple 50V Bench Power Supply Circuit Diagram

An 50v bench power supply can be made using electronic diagram below which is designed using LM10 op amp and 2n3055 transistors. This LM10 2n3055 50v bench power supply allows an output voltage regulation in a range between 0 and 50 volts and the output current can be limited to a maximum of 2A. Output voltage increases linearly with the amount of resistance potentiometer P1, while the current can be adjusted linear using potentiometer P3. Potentiometer P2 serves to regulate maximum output current (maximum value is 2A).

8 Amp Regulated Power Supply circuit Wiring diagram

This power supply is powered by a transformer operating from 120 Vac on the primary and providing proximately 20 Vac on the primary, and providing approximately 20 Vac on the secondary. Four 10-A diodes with a 100 PIV rating are used in a full-wave bridge rectifier.

8-Amp Regulated Power Supply Circuit Diagram

A 10,000 ^F/36 Vdc capacitor completes the filtering, providing 28 Vdc. The dc voltage is fed to the collectors of the Darlington connected 2N3055s. Base drive for the pass transistors is from pin 10 of the µ723 through a 200 ohm current limiting resistor, Rl. The reference terminal (pin 6) is tied directly to the non-inverting input of the error amplifier (pin 5), providing 7.15 V for comparison.

The inverting input to the error amplifier (pin 4) is fed from the center arm of a 10 k ohm potentiometer connected across the output of the supply. This control is set for the desired output voltage of 13.8 V. Compensation of the error amplifier is accomplished with a 500 pF capacitor connected from pin 13 to pin 4. If the power supply should exceed 8 A or develop a short schema, the µ723 regulator will bias the transistors to cutoff and the output voltage will drop to near zero until the short schema condition is corrected.

Saturday, August 30, 2014

10 KV High Voltage Power Supply Wiring diagram Schematic

This is very sensitive this is a 10 KV High Voltage Power Supply Circuit Diagram. Be very careful with this power supply because uses 220V mains and has 10KV at output.

10 KV High Voltage Power Supply Circuit Diagram

Thursday, August 28, 2014

Now 0 to 40V Lab Power Supply

A very lab adjustable power supply that can provide an output voltage between 0 and 60 volts can be designed using this schema diagram . This lab power supply can be designed with LM723 chip or for higher output voltages, with L146 .Output current is also adjustable, but once established, is always effective. Table 1 shows the values to be modified to have three different versions of the maximum output voltage (30, 40 and 60 V).

0 to 40V Lab Power Supply Circuit Diagram

Electrical diagram below shows the alternative 40 V / 0.8 using L146 chip because it can stabilize higher output voltage, much better than the LM723. Normally, 2 V is the minimum voltage stabilized that even an integrated schema can provide. Resistive network R3, R4 and R5, R6 "kill" this restriction so that output can be set to 0 V with potentiometer P2.

Depending on the output requirements, will be decided on the type and the semiconductor capacitors to be used. Output current must be limited so as to keep power dissipation of 40 W. T3 under maximum output current for 40 V version is 0.8 A. It can connect two parallel 2N3055 transistors (with emitter resistors) to double the current output, but in this case requires a 2 A transformer

Wednesday, August 27, 2014

Build a 5V Supply Wiring diagram Schematic

This 5V Supply Circuit Diagram protects microprocessor systems from `brownouts` without the expense of an uninterpretable power supply. Designed around a small 9-V nickel cadmium battery the schema continues to provide a constant 5-V output during brownouts of up to a few seconds. Load currents of up to 500 mA may be drawn using the components shown.

With this mains-derived supply present, D5 is forward biased so that the stabilized supply powers the 5-V regulator and hence the schemary to be protected. FET Tj is held on by Dl, its drain current being provided from the dc supply via Rb and D2. Diode D3 is reverse-biased so that T2 is off, and the battery is isolated from D6. RCH and D4 serve to trickle charge the battery with approximately 1.2 mA.

5V Supply Circuit Diagram

When the 12-V supply is removed, Rl and Cl initially keep Tl switched on. D3 is now forward biased, so that Tl drain current is drawn via Rb, D3 and T2 from the battery. This switches T2 on, allowing the load schemary to draw current from the battery via D6 and the 5-V regulator. After a few seconds Cl has discharged (via Rl) such that Vgs falls below the threshold value for the FET, and Tl switches off. There is then no path for T2 base current, so that it also switches off, isolating the battery.

Build a Power supply Protection Wiring diagram Schematic

Why Build a Power supply Protection Circuit Diagram. When using a regulated supply to reduce a supply voltage there is always the danger of component failure in the supply and consequent damage to the equipment. A fuse will protect when excess current is drawn, but might be too slow to cope with over voltage conditions. The values shown are for a 12 V supply being dropped to 5 V.

Power supply Protection Circuit Diagram

The trip voltage is set to 5.7 V to protect the equipment in the event of a regulator fault. The 330 ohm resistor and the 500 ohm potentiometer form a potential divider which samples the output voltage as set by adjustment of the potentiometer. The SCR is selected to carry at least twice the fuse rating. The full supply voltage is connected to the input of the regulator.

The 2N2906 is held bias off by the 10 k resistor and the SCR so that the LED is held off. If the output voltage rises above a set trip value then the SCR will conduct, the fuse will blow, and the 2N3906 will be supplied with base current via the 10 k resistor, and the LED will light up.

Monday, August 25, 2014

Supply Variable 1V to 9V Circuit using Power PC

This is a variable power supply which converts an input voltage from 12V SMPS / PSU a desktop computer, to an output voltage from 1.25 to 9 volts. This converter will be very useful for electronics hobbyists.

The schema uses a LM317T regulator IC that can reach up to 1 ampere, the diode D1 protects against polarity reversal and the diode D2 keeps the output voltage from the input voltage increases when an inductive or capacitive load is connected to the output.Similarly, the capacitor C3 removes any residual noise of the line regulates the voltage potentiometer VR1.

Supply Variable 1V to 9V using Power PC Circuit Diagram

Sunday, August 24, 2014

2V to 25V 5A LM338 Power Supply Circuit

2V to 25V LM338 Power Supply Circuit

This project uses a LM338 adjustable 3 terminal regulator to supply a current of up to 5A over a variable output voltage of 2V to 25V DC. It will come in handy to power up many electronic diagram when you are assembling or building any electronic devices. The schematic and parts list are designed for a power supply input of 240VAC. Change the ratings of the components if 110VAC power supply input is required.

As shown in the figure above, the mains input is applied to the schema through fuse F1. The fuse will blow if a current greater than 8A is applied to the system. Varistor V1 is used to clamp down any surge of voltage from the mains to protect the components from breakdown. Transformer T1 is used to step down the incoming voltage to 24V AC where it is rectified by the four diodes D1, D2, D3 and D4. Electrolytic capacitor E1 is used to smoothen the ripple of the rectified DC voltage.

Simple 15V And 5V Car Battery Supply Wiring diagram Schematic

This is a Simple 15V And 5V Car Battery Supply Circuit Diagram. In this schema use IC1 is a switching regulator that generates a 45-kHz signal that drives the gate of MOSFET Ql. Dl, D2, and D3 are Schottky diodes. The 5-V output is sensed as a reference; feedback to the chip turns off the gate signal to Ql if the voltage rises above 5 V.

Tl has Trifilar windings that assume about 2% regulation for a 10-to 100-mA load change on the Â± 15-V supplies. R1/D4 provide over-voltage protection. Tl has a primary inductance of about 21 . Core size should allow 4-A peak currents. The turn ratios are IIV2 turns each for the 15-V supplies, ll1/2 turns for the primary, and four turns for the 5-V secondary. The efficiency is about 75%.

Simple 15V And 5V Car Battery Supply Circuit Diagram

Saturday, August 23, 2014

9 Volt 2 Amp PSU Single IC Regulator Power Supply

Notes

There is little to be said about this schema. All the assignment is done by the regulator. The 78S09 can bear up to 2 amps connected achievement whilst advancement a low babble and actual able-bodied adapted supply.

The ambit will assignment after the added components, but for about-face polarity aegis a 1N5400 diode is provided at the input, added cutting actuality provided by C1. The achievement date includes C2 for added filtering, if powering a argumentation ambit than a 100nF capacitor is additionally adorable to abolish any aerial abundance switching noise.

via : http://www.zen22142.zen.co.uk/Circuits/Power/9v2a.htm