Introduction to DC/DC Power Module

Power Module

The power module is a power supply that can be directly mounted on a printed circuit board. It has two types: step-down and step-up. Its characteristics are that it can provide power for application-specific integrated circuits (ASICs), digital signal processors (DSPs), microprocessors, memories, field programmable gate arrays (FPGAs) and other digital or analog loads.

DC/DC Power Modules

DC-DC is realized by the idea of ​​switching power supply. There are two types of DC-DC: step-down and step-up. Here we only talk about step-down. For example, if you input 10V to the DC-DC, there is an oscillator and chopper module inside the DC-DC. For example, 10V is allowed to pass in one time period, and 10V is not allowed to pass in another time period (equal to 0V). There is a capacitor at the output end for filtering. As long as the capacitor is large enough, the result is equal to the calculus of the pulse waveform in the middle, and a 5V DC waveform is output.

Compared with the voltage regulator module, this step-down process avoids the consumption of electric energy on the step-down module to a greater extent, and the internal oscillation part controls its duty cycle to change the output voltage (within the range of 10V) so that its output can be constant (for example, a DC-DC specifies an input range of 6V to 16V and an output of 5V. As long as it is within this input range, the output is 5V with an error of only a few tenths of a volt, and the output of the voltage regulator module has a certain linear relationship with the input voltage. The output voltage of an input of 7V is quite different from the output voltage of an input of 14V)

Advantages of using power modules

At present, different suppliers have launched a variety of different power modules on the market, and the input voltage, output power, function and topology of different products are different. The use of power modules can save development time and enable products to be launched on the market faster, so power modules are better than integrated solutions. Power modules also have the following advantages:

● Each module can be rigorously tested individually to ensure its high reliability, including power-on testing to eliminate substandard products. In contrast, integrated solutions are more difficult to test because the entire power supply system is closely linked to other functional systems on the circuit.

● Different suppliers can design modules of the same size according to existing technical standards, providing engineers designing power supplies with a variety of different options.

● Each module is designed and tested in accordance with standard performance requirements, helping to reduce the risks of adopting new technologies.

● If an integrated solution is used, once a problem occurs in the power supply system, the entire motherboard will need to be replaced; if a modular design is used, only the problematic module needs to be replaced, which helps save costs and development time.

Features

※ Small size and high reliability;

※ Output voltage regulation, accuracy can reach ±3%;

※ High performance-price ratio;

※ Various input and output voltages;

※ Built-in input filter, low electromagnetic compatibility characteristics;

※ Aluminum shell is frosted and oxidized, with six-sided shielding.

※ Typical applications: industrial instruments, digital circuits, electronic communication equipment, satellite navigation, remote sensing and telemetry, ground communication and scientific research equipment, etc.

1. Input characteristics

Input voltage range:

4.75VDC - 5.25VDC

11.40VDC - 12.60VDC

14.25VDC - 15.75VDC

22.80VDC—25.20VDC

45.60VDC—50.40VDC

2. Output characteristics

Output voltage accuracy: nominal output voltage ±3%

Load effect: 20% to 100% load change

≤±1.0%(maximum value)

Source effect: When the input voltage changes from low end to high end

≤±1.0%(maximum value)

Ripple and noise: ≤50mVpk-pk (maximum value)

Temperature coefficient: ≤±0.02%/℃ (maximum value)

3. Isolation voltage : input to output (leakage current <2mA for 1 minute) 1000VDC

Storage temperature: -40℃ to +120℃

Relative humidity: 10RH～90RH

Operating temperature: -25℃ to +85℃

Maximum shell temperature: +90℃

Main application areas of module power supply

Module power supply is used in several aspects

1. Electricity, mainly integrators, meters and smart meters

2. Industrial control, industrial control field

3. Medical treatment, medical equipment, mainly including fetal protection devices, monitors, etc.

4. Military industry: Military industry is a very widely used area. In military equipment.

Several major indicators of DC/DC power supply

Power P=UI, which is the product of output voltage and output current.

There are two types of input voltage: AC input and DC input.

The output voltage is generally DC output, but there is also AC output.

Operating temperature

Isolation voltage: Isolation is the circuit separation of output and input. It has the following functions:

1. Current conversion;

Second, to prevent input and output from interfering with each other;

Third, the signal characteristics of the input and output circuits are too different, such as using weak signals to control strong electrical equipment

The package sizes include pin, SMD, and spiral.

The output has single output, dual output and multiple output. The power module is a power supply that can be directly mounted on a printed circuit board. Its characteristics are that it can provide power for application-specific integrated circuits (ASICs), digital signal processors (DSPs), microprocessors, memories, field programmable gate arrays (FPGAs) and other digital or analog loads. Generally speaking, this type of module is called a point-of-load (POL) power supply system or a point-of-use power supply system (PUPS). Due to the many advantages of the modular structure, modular power supplies are widely used in communication fields such as switching equipment, access equipment, mobile communications, microwave communications, optical transmission, routers, and automotive electronics, aerospace, etc.