There is a significant difference in circuit structure between the switching power supply and the linear power supply.
Switching regulated power supply is a kind of DC-DC converter, which realizes stable DC output voltage through the process of chopping, filtering and voltage regulation. At its core are pulse width modulation (PWM) switches and energy transmission systems. This power supply usually contains four basic components: the main circuit, the control circuit, the detection circuit and the auxiliary power supply. The main circuit mainly includes a rectifier circuit, a chopper circuit and a filter circuit, and the control circuit realizes pulse width modulation to control the on-off and cutoff time of the switch, while the detection circuit samples the output voltage to ensure that the output voltage is within the specified range.
The linear voltage regulator power supply changes and controls the output voltage and current by adjusting the transistor's conduction degree. Compared with the switching power supply, the circuit of the linear power supply is simpler, mainly composed of regulating tube, reference voltage, sampling circuit and error amplifier. The advantages of linear regulated power supply are simple circuit design, good stability and small noise, but the disadvantage is that the efficiency is low and the heat is serious, so a larger radiator is usually required.
In short, switching power supply and linear power supply have essential differences in circuit structure, and application scenarios are different. The choice of power supply mainly depends on the specific application requirements and design requirements.
A: The difference between the switching regulated power supply and the linear regulated power supply in the circuit structure is that the transformer in the circuit does not work at the power frequency but works at tens of kilohertz to several megahertz. The power tube does not work in the linear region, but in the saturation and cut-off region, that is, it works in the switching state; Switching DC power supply is also named for this. The switching power supply is roughly composed of the main circuit, control circuit, detection circuit and auxiliary power supply.
Switching power supplies are suitable for the full voltage range, no differential pressure is required, and different circuit topologies can be used to achieve different output requirements. The adjustment rate and output ripple are not as efficient as linear power supplies. Many peripheral components are required and the cost is high. There is also the complex design of the switching power supply circuit, high failure rate, and inconvenient maintenance.
Switching Mode Power Supply (SMPS) and Linear Regulator are two common types of regulated power supplies. Their main difference lies in the circuit structure:
1. Switching power supply:
Switching regulator power supply by controlling switching devices (such as MOSFET, IGBT, etc.) on and off, the input voltage is chopped, so as to achieve voltage transformation and stability. The chopper voltage is filtered and rectified to obtain a stable output voltage. Switching regulated power supply has the advantages of high efficiency, high power density and low noise, but the circuit is relatively complex and the cost is high.
2. Linear stabilized power supply:
The linear voltage regulator achieves voltage stability by adjusting the bias deviation of the transistor. This type of power supply usually includes an input filter circuit, a rectifier circuit, a linear regulator and an output filter circuit. Linear power supply has the advantages of simple circuit, low cost and low noise, but the efficiency is low, and when the input voltage and output voltage difference is large, the need to select high-power transistors, resulting in an increase in volume and weight.
In short, switching power supply and linear power supply have their advantages in their respective application fields. Which power supply to choose depends on the specific application needs, such as efficiency, size, cost, noise, etc.
A switched regulated power supply usually consists of four main parts: an input, an output, a control chip and a rectifier\/filter. The input end of the switching regulator power supply is connected to the power grid, the output end is connected to the load, and the control chip in the middle is responsible for controlling the operation of the entire circuit. Switching voltage regulator power supply has high efficiency, can provide more stable output voltage, and is suitable for high voltage stability requirements.
The linear regulated power supply usually consists of a thyristor or a field effect tube. The input end of the linear voltage regulator power supply is also connected to the power grid, and the output end is also connected to the load, but its working principle is different from the switching voltage regulator power supply. The output voltage is regulated by controlling the switching state of the thyristor or the field effect tube
1. In the circuit structure, there is a clear difference between the switching voltage regulator and the linear voltage regulator.
2. Switching voltage regulator power supply uses switching devices (such as MOSFET) to control the switching state of the input voltage, and adjusts the stability of the output voltage by constantly switching.
The linear voltage regulator realizes the stable adjustment of the output voltage by adjusting the working state of the resistor or transistor.
3. Switching regulated power supply has higher efficiency and smaller volume than linear regulated power supply.
Because the switching frequency of the switching device is high, it can respond more quickly to voltage changes, so the switching regulator power supply can be adjusted more quickly.
The linear regulated power supply is relatively slow. 4. In addition, the switching voltage regulator can also adjust the output voltage by controlling the duty cycle of the switching device, while the linear voltage regulator needs to adjust the working state of the resistor or transistor. 5. In general, the switching voltage regulator power supply has obvious differences from the linear voltage regulator power supply in the circuit structure, with higher efficiency, smaller volume and faster adjustment speed.
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The difference between switching power supply and linear power supply:
1. The difference between switching power supply and linear power supply is that their working principle and structure are different.
2. The input voltage of the linear power supply is directly sent to the regulator after the transformer is stepped down, and the regulator adjusts the voltage and outputs a stable DC voltage. Because its basic circuit is linear, it has good voltage regulation but relatively low efficiency.
3 Switching power supply is the use of high-frequency pulse circuit to input voltage into high-frequency AC voltage, and then through the transformer into the required voltage, and then through the voltage regulator circuit for the final voltage regulator output, its high efficiency, and weight and size is small, often used in computer, communication and other fields.
4. Therefore, the difference between switching power supplies and linear power supplies mainly lies in their stability, efficiency, size and weight.
Linear power supply and switching power supply are two common power supply types, and their main differences are in terms of working principle, efficiency and weight.
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1. How it works
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The principle of linear power supply is to convert the input alternating current into a stable direct current output. Its basic structure is composed of transformer, rectifier bridge, filter capacitor, voltage regulator circuit and power amplifier, which can realize the precise control of voltage.
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The switching power supply adopts high-frequency switching technology, and the input power supply is time-shared controlled through the switching tube, so that the voltage, current and other parameters can be quickly adjusted and the output can be stabilized.
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2. Efficiency
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The efficiency of the switching power supply is often higher than that of the linear power supply, and the efficiency of the switching power supply can still maintain a high level when the load changes greatly. The efficiency of linear power supplies will gradually decrease with the increase of load.
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Step 3: Weight
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Because linear power supplies require the use of large transformers and radiators, they are relatively bulky. The switching power supply uses lightweight materials and small components, which can be more lightweight and compact.
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In summary, linear power supplies are suitable for applications that require high stability, such as amplifiers, precision instruments, etc. The switching power supply is suitable for applications with high power, high efficiency and light weight, such as computers, mobile phone chargers, LED lighting and so on
There are several major differences in circuit structure between switching and linear regulated power supplies.
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The working state of the adjustment tube: the adjustment tube in the linear voltage regulator power supply works in the amplified state, while the adjustment tube in the switching voltage regulator power supply works in the saturated and cut-off state.
Voltage conversion mode: The linear voltage regulator adjusts the output voltage by adjusting the linear current change of the input tube, while the switching voltage regulator controls the output voltage by adjusting the full on-off and full cutoff of the tube.
Heat dissipation design: Because the adjustment tube in the linear voltage regulator power supply works in the amplified state, its power consumption is relatively large, and better heat dissipation design is needed. The regulating tube in the switching regulator power supply works in the saturation and cut-off state, the power consumption is small, and the heat dissipation design is relatively simple.
Circuit structure: The linear voltage regulator power supply usually consists of an error amplifier, a reference voltage, a sampling circuit, a regulating tube and an auxiliary power supply. On this basis, the switching power supply also adds the pulse shaping circuit, pulse width modulator, switching transformer and rectification filter.
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In summary, the difference between the switching voltage regulator and the linear voltage regulator in the circuit structure is mainly reflected in the working state of the adjustment tube, the voltage conversion mode, the heat dissipation design and the overall circuit structure.
Switching regulated power supply and linear regulated power supply are common power supply design types, and they have great differences in circuit structure.
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Switching regulated power supply adopts switching tube (MOSFET or IGBT) as switching element, converts input voltage into high frequency pulse signal, filters and adjusts through inductance and capacitor, and finally outputs stable DC voltage. The switching voltage regulator has the advantages of high output voltage accuracy, high efficiency, small size, light weight, etc., which is suitable for the occasions requiring high efficiency and high output power. However, switching regulated power supply also has some disadvantages, such as the switching loss of the switching tube is larger, the noise is larger, and the power grid fluctuation is sensitive.
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Linear power supply adopts linear feedback circuit to realize the stability of output voltage. It adjusts the resistor, capacitor and inductor in the circuit, so that the change of output voltage can be timely feedback and suppression. The linear power supply has the advantages of stable output voltage, low noise and high reliability, and is suitable for the occasions where the quality of the power supply is required. However, linear power supply also has some disadvantages, such as low efficiency, limited output current, and sensitive to load changes.
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Therefore, the choice of switching power supply or linear power supply needs to be selected according to the specific application scenarios and needs.