Power technology is extensive and profound, and its application fields are also very extensive, from industry and automobile to photovoltaic and medical care. A complete power supply requires the combination of many modules, among which the power supply module is the most critical part. There are also many domestic companies engaged in the research in this field. For engineers, the heating of power supply module is a common problem.

1. What is the power module?

The power module is a power supply that can be mounted directly on a printed circuit board. It is characterized by providing power for specialized integrated circuits (ASIC), digital signal processors (DSP), microprocessors, memory, field programmable gate array (FPGA), and other digital or analog loads.

In general, such modules are called load point (POL) power supply systems or use point power supply systems (PUPS). Because of the advantages of modular structure, module power supply is widely used in switching equipment, access equipment, mobile communication, microwave communication, optical transmission, router and other communication fields, automotive electronics, aerospace and so on.

Power supply module with energy loss in voltage conversion process, generate heat cause module heating, reduce the conversion efficiency of power supply, influence the normal work of the power supply module, and may affect other devices around the performance of this kind of situation need to screen immediately, according to a senior engineer to feedback to the author, there are so many ways to solve the heating power supply module, the following are some common techniques.

2. Methods to solve the heating problem of power module

The use of a linear power source causes heat: the linear power source works by adjusting the RW of the tube to change the size of the output voltage. Since the regulating tube is equivalent to a resistor, the current passing through the resistor will generate heat, resulting in low efficiency. In order to prevent the power module from heating seriously, the following measures can be taken, such as increasing heat dissipation fins, implementing air cooling, solving thermal conductive materials (thermal silicone grease, thermal potting sealant), and switching to switching power supply.

The load is too small not suitable: the power supply light load, that is, the power supply circuit load impedance is relatively large, then the power supply to the load output current is relatively small, some power supply circuits do not allow the light load of the power supply, otherwise it will make the power supply circuit output DC working voltage increased a lot, causing damage to the power supply circuit. General power modules have a minimum load limit, which varies from manufacturer to manufacturer, generally 10%. If the output load is too light, it is recommended that a dummy load resistor be connected in parallel at the output.

Load overcurrent problem: the power supply is overloaded, which is the opposite of the light load of the power supply, that is, the load circuit of the power supply circuit has a short circuit, making the power supply circuit output a large current, and beyond the range of the power supply can bear. For the power module without overcurrent protection, the simplest way to output voltage regulator, overvoltage regulator and overcurrent protector is to connect the linear voltage regulator with overcurrent protection outside the input end.

Excessive ambient temperature or poor heat dissipation: Before using the module power supply, it is necessary to consider the temperature level of the power supply module and the actual operating temperature range, and perform the de-scaling design according to the load power and the actual ambient temperature.

The heating of power module is a problem that troubles a lot of power engineers. At ordinary times, engineers can refer to the advice of this engineer and try to solve this problem.