Buyers who are new to power-related products are often confused about the different types of power supplies. In order to power an electronic device or system, matching the correct power supply is important. It starts with understanding the different types of power supplies. Here we will make a simple classification and explanation, hope to help you understand it better.
1. Classification according to input/output
The simplest but the most useful way of classification, it’s very easy to understand and very important to understand as well.
If the end system needs AC or DC power at the desired voltage and power requirements, when the wrong power supply has been provided, it may cause some big issues. Using a suitable power supply to convert the AC/DC input voltage is important and the involves considering factors including power efficiency, and stability over temperature……
1.1. A sheet to help you understand
| Type | Define | Examples | Application |
| AC to AC power supply | Input and output are alternating currents; step up or step down voltage by using a transformer | Transformer Frequency changer/converter Variable AC power supply Isolation transformer | As a transformer component, normally used inside an electronic device for change the voltage and frequency; others used separately to change the voltage, harmonics, frequency |
| AC to DC power supply | Input from alternating current, the output is DC voltages | Wall wart Desktop/Bench power supply Battery charger Linear Power Supply SMPS(Switch Mode Power Supply) | Usually used as an external power supply for most electronic devices such as cellphone, laptop, printer…… |
| DC to AC power supply | Input from DC voltage, convert and output it to be an AC voltage | Inverter Generator UPS(uninterruptable power supplies) | The most common use is UPS, normally used as a car’s battery or as portable power to convert the DC power to useful AC power that can power the car or some home devices |
| DC to DC power supply | converts a direct current input supply to a DC output supply at a different voltage level | DC-DC converter SMPS(Switch Mode Power Supply) DIN Rail power supply | Used inside electronic equipment normally, modifies the voltage and the shape of the wave |
1.2. Reference pictures for the above power supply types
1.2.1. AC to AC power supply
1.2.2. AC to DC power supply
1.2.3. DC to AC power supply
and UPS all include the function to convert the DC power to useful AC power.
1.2.4. DC to DC power supply
2. Classification according to Technology
Power supplies are a must for general electronic products to provide power. Based on different technology, we could classify different power supplies and it will help us to understand better how the power supply works.
| Type | Define | Application |
| Linear power supply | AC input voltage passes through a large transformer to drop voltage and is then rectified and filtered processing to obtain a clean DC voltage. | Generally used for medical equipment, low noise amplifiers, data acquisition, test equipment, and other equipment that requires excellent regulation and/or low ripple |
| Switched-mode power supply | Called switching power supply also, helps electronic devices to obtain a directly DC voltage from rectified AC mains input through filtering. The obtained DC voltage will then be switched on and off at a very high frequency by electronic switching circuitry and will be regulated through a processing called pulse width modulation (PWM). | Switching power supply’s application is very wide and works almost anywhere in the world, for example, railway system, security system, DC motors, factories for power, also used in mobile and also as lighting… |
| Capacitive (transformerless) power supply | Uses the reactance of a capacitor to reduce the mains voltage to a smaller AC voltage, then rectified, filtered, and regulated to produce a constant DC output voltage. | Normally used for low voltage electronic devices, such as toys, mobile, led bulbs, emergency lights…… |
| Programmable power supply | Called PPS also, allows remote control of its operation through an analog input or digital interface. Controlled properties may include voltage, current, and frequency. | Used in very wide applications, including x-ray generators, automated testing equipment for factories, laboratories etc, crystal growth monitoring, and x-ray generators….. |
| High-voltage power supply | Using a special output connector to output hundreds of thousands of volts, which prevents arcing, insulation breakdown, and accidental human contact. | Used in the field that requires high voltage, such as medical imaging, manufacturing, X-Ray, Power Distribution, generate electron beams…… |
| Uninterruptible power supply | Called UPS also, takes its power from two or more sources simultaneously. Usually, it gets powered directly from the AC mains, in the meantime charging the battery built-in. If there is a dropout or failure of the mains, the battery instantly powers the load so that it never experiences an interruption. | Commonly used as a car’s battery or as portable power to convert the DC power to useful AC power that can power the car or some home devices |
| Bipolar power supply | It generates positive and negative voltages and currents as required to maintain regulation by operating in all four quadrants of the voltage/current Cartesian plane. | Normally used to power magnetic devices in scientific applications. |
3. Classification according to Mounting methods
3.1. Classification
| Type | Define | Application |
| Wall plug power supply | Plug in the wall for AC power source directly | Normally used for home appliances electronics, such as mobiles, printers, toys, speakers…… |
| Wall Mount Power supply | Power supply mounting on the wall | Mounted on the wall to provide power for home or industry |
| Desktop/Benchtop power supply | Put on the benchtop and use a power cable to connect the source | The Common use for Medical, laptops, Electric Vehicles, Industrial Automation/Robotics…… |
| DIN Rail Mountable Power Supply | Mount on a din rail for fixing | Mounted on a din rail of big equipment, normally for factories or other industrial use |
| Enclosed Power Supply | An enclosure includes one or more power supplies | All power supplies enclosed with an enclosure are enclosed power supplies, that could provide power for electronic equipment and devices |
| Rack Mount Power Supply | Power supply mounting on Rack of Equipment | Mounted on a Rack of big equipment, normally for factories or other industrial use |
| Portable Power Supply | The power supply could be moved and carried easily | Power bank, and big portable power supply for outdoor use such as camping, fishing…… |
3.2 Reference Pictures
The classification will be updated in the future, please let me know in the comment if you want to keep posted. And If there is anything wrong with this article please contact or comment to me.
