A power supply is an electronic circuit that converts an ac voltage to dc voltage. It is basically consisting of the following elements: transformer, rectifier, filter and regulator circuits. Power supply units (PSU) are used in computers, amateur radio transmitters and receivers, and all other electronic equipment that use dc voltage as an input. Uninterruptible power supply is a must for computers which holds volatile data from time to time. This prevents corruption of data due to power failure and low voltage. TransformerThe transformer is a static device that transfers electrical energy from the primary winding to the secondary winding without affecting the frequency. It is used to step-up or step-down the ac voltage level and isolates the remainder of the electronic system from the ac power. The primary winding of the transformer is connected to an ac voltage source that produces alternating current while the secondary is connected to a load. The primary and secondary windings are not physically connected to each other but due to electromagnetic induction following Faraday's law, there is an induced voltage in the secondary winding.

There are three main functions of transformers namely: stepping the voltage up, stepping the voltage down and providing isolation between the primary and secondary circuits. RectifierThe rectifier is a device used to change the ac power into pulsating dc. The basic rectifier is the diode. This diode is a unidirectional device that operates as rectifier in the forward direction. The three basic rectifier circuits using diodes are the half-wave, full-wave center-tapped and full-wave bridge type. FilterThe filter of the power supply is used to keep the ripple component from appearing in the output. It is designed to convert pulsating DC from rectifier circuits into a suitably smooth dc level. The two basic types of power supply filters are the capacitance filter (C-filter) and RC-filter. The C-filter is the simplest and most economical filter available. On the other hand, RC-filter is used to reduce the amount of ripple voltage across a capacitor filter. Its primary function is to pass most of the dc component while attenuating the ac component of the signal.

Ripple and Ripple factor Ripple is the unwanted ac component of the signal after rectification. It is unwanted because it can destroy or damage the load. This is the main reason why filters are installed in power supply - to prevent high ripples. The job of the filter is to smoothen the signal and suppress the ac component or variations. Ripple factor is the ratio of the root mean square of the ripple voltage to the value of dc component at the output voltage. It is sometimes expressed in percentage or in peak-to-peak value. The ripple factor determines the effectivity of a filter being used in the circuit. Voltage RegulatorsA voltage regulator is designed to provide a very steady or well regulated dc output. It is always ideal to have a steady output voltage so that the load will operate properly. The output level is maintained regardless of the variation of the input voltage. The commonly used transistor voltage regulators are the series voltage regulator and the shunt voltage regulator.

The series element controls the amount of the unregulated input voltage that goes to the output as a regulated output. battery power ac dcThe regulated output voltage is sampled by a circuit that provides a feedback to the comparator circuit and is compared to a reference voltage.car air conditioner repair tips The shunt voltage regulator provides regulation by shunting current away from the load to regulate the output voltage.cost to install second ac unit IC Voltage RegulatorsA regulator Integrated Circuit (IC) unit contains the circuitry - the reference source, comparator, amplifier, control device, and the overload protector - inside a single IC. There are also adjustable voltage regulators which allow the user to set the desired output level.

Other IC regulators have fixed output values. It is said that IC regulators are superior compared to transistor voltage regulators when it comes to linearity of the output voltage. I'm wanting to start my own lab at home so that I can learn things faster than uni teaches (we're not allowed into labs unless we're in our own lab). A friend said that I'd be better off getting a power supply than a function generator, since I'm a first/second year elec student because he thought they'd be cheaper, but there's only about $50 difference between the two. I'm actually wondering whether it would be a good idea to get the Rigol DG-1022, and to supply a dc source, I set the frequency as close to zero as possible. Of course, electricity is dangerous; while I'm cool with blowing an LED or op-amp, I'm not at all happy to assume that a mock dc supply is actually direct current, without first checking if this is safe. Wondering what you think? I'm not just asking about safety, if you've got other comments, I'm happy to hear them.

power-supply ac dc safety function-generator No, that won't work. You could use fixed voltage supplies (AC adapters, wall warts) for most power supply purposes - just understand that your circuits are living dangerously if the supplies aren't current limited, so be careful and double-check your connections - until you can afford an adjustable PSU. One option is to make one of your first projects an adjustable PSU with current limiting (using an LM317 and a heatsink) powered by an AC adaptor, perhaps a 19V one from an old laptop. It'll teach you about proper heatsinking! So I'd still go for the function generator as a first purchase (assuming you already have a multimeter!) but use other arrangements to supply power. The function generator you are referring to is an arbitrary waveform generator. You can actually punch in a DC signal and live with that. The specs on the rigol site states that the maximum peak to peak output voltage for channel 1, that is the stiffest, is 10V on a load of 50\$\Omega\$.

Assuming the output is ground referenced you have some 5V on 50\$\Omega\$, i.e. 100mA. That is a ridiculously low current for any project this side of turning on an LED. For most projects you will need a dual power supply, sometimes you will need dual power supply plus another positive voltage for digital circuitry, and the signal generator can't help that. 5V is also quite a low voltage if you want to make any decent audio circuit or anything more than some Watts powerful, maybe a stepper driver or whatever. A signal generator as a power source is definitely a bad idea, you should really consider getting a decent bench power supply. You could also use a wall wart or something like that, that is much cheaper, but I advise against it. You will blow things up and having a current limited, nice stiff 'n steady supply is something you should not skip over. Plus you can use your laptop as a signal generator through its audio output: it's a kinda hacked solution but it's much better than using a signal generator as PSU and I think it is also better to have a nice PSU and a hacked signal generator than the opposite thing.

If you are only powering low wattage circuits then a function generator can work. I've used them to generate an AC output (like the low voltage output of a transformer) and fed that into a bridge rectifier and smoothing capacitor to power small circuits. Most function generators will have at least 50 ohms in series with the output and might produce up to 10Vp-p (hand waving alert) so for a moderate load they will work. If you need more than a couple of watts then buy/build a power supply. If you want simple and relatively good power supply, you could get yourself an old computer power supply, you will have 5 and 12 volts with good stability, and invest your money in a signal generator(or a scope..It is not hard to create a variable power supply with an lm317 circuit or something which is actually a good project for a novice :) the rigol scope like a ds1054z is only 399 and you will learn a lot, you have cheap signal generators for about 20-25 $ on ebay, just be aware that they are CHEAP, and their signals are not that well formed(which you could investigate with your scope), but it does get you started.