Author - March 29, 2018

Anatomy of Switching Mode Power Supply

The introduction.

Power Supply used in PC based on a technology called “switching mode” and thus also known as SMPs, Switching Mode Power Supplies (DC-DC converter is another name for this power supply). In this tutorial we will explain how to power supply switching works and I will show you your PC’s power supply is mainly the main components and what its function.

There Are Two Basic Design Of Power Supply: Linear And Switching.

Linear power supply works with input voltage 127 V or 220 V and then lowered into the low voltage (for example, 12 V) by using a transformer. This low voltage the still air conditioning Then rectification performed by a set of diodes, the voltage change AIR CONDITIONING is becoming  pulsating voltage (number 3 in Figure 1 and 2). The next step is screening, the

performed by capacitor elektrolitik, this transformation then becomes the DC voltage (number 4 on Figure 1 and 2). DC capacitor obtained after oscillating a bit (this is called ripple oscillations), so the stage set the required voltage, then performed by the zener diodes or by circuit the integrated voltage regulator. After this stage the output DC voltage is pure (# 5 in Figure 1

and 2).


Figure 1: Block diagram for standard linear power supply design.

Figure 2: wave form on linear power supply.

Although linear power supply works very well for some low power applications; the phone without cable and video game console, but when high power is needed, a linear power supply can be literally is very heavy for the task.

The size of the transformer and the capacitor capacitance of elektrolitik are inversely proportional to the

the frequency of the AC voltage input: AC voltage, the lower the frequency, the larger the size of the components and vice versa. Because the power supply is still using linear frequency 60 Hz (or 50 Hz, depending on the country) from the electricity network which is a very low frequency,

the transformer and the capacitor should be very large.

The power supply used on a PC using a better approach: i.e. a loop system

covered. A series of controlled switching transistors get feedback from the output of the power supply

power, increase or decrease the cycle of the voltage at the transformer in accordance with consumption

PC (this approach is called PWM, Pulse Width Modulation). So power supply reset with itself depends on the consumption of the devices connected.

If your PC does not consume a lot of power, power supply reset itself to rest, make a transformer and all the other components to eliminate power more smaller little heat is generated. On linear power supply, regulated power supply to provide power

maximum stay, even if the circuit is connected in a State doesn’t work. The result is a that all components are working at full capacity, even though it is not required. The result greater is the heat.

Switching Power Supply Diagram

In Figure 3 and 4 you can see the block diagram of switching power supply with PWM feedback behind that is used on a PC. In Figure 3 we present the block diagram power supply without circuit PFC (Power Factor Correction)-used by cheap power supplies and in Figure 4

We block diagram shows power supply with Active PFC circuit, used in Power Supply high end.

Figure 3: Block diagram of switching power supply with PWM design (without PFC).

Figure 4: Block diagram of switching power supply with PWM design (with PFC).

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