Too high or too low output voltage is not good. Today, let's talk about how to solve the problem of too low output voltage. What is the problem with the output voltage? It may cause the whole system to fail to work normally. For example, when the voltage is too low, the bulb is not bright or dark, which must not meet our needs. If the voltage is too low for a long time, the circuit life will be greatly reduced. How can we solve this problem?
One of the most important indexes of bare board power module is the output voltage accuracy. When testing the accuracy of power supply voltage, some engineers feed back that the output voltage is low, which can not meet the accuracy requirements given in the technical manual. Why? Is the test method wrong or the product itself bad?
Generally speaking, it can be carried out by exclusion method. Firstly, it is assumed that the product is good, and the test is carried out according to the test method given by the manufacturer. If there are still problems, it can basically be judged that it is caused by inferior products.
First, let's analyze what causes the output voltage to be too low so that we can prescribe the right medicine.
Low input voltage or insufficient power; The output line is too long or too thin, resulting in excessive line loss;
The voltage drop of the reverse diode at the input is too large; The input filter inductance is too large.
How can we solve the above four reasons? Let's take a look at this road.
Adjust the voltage or switch to a larger power input power supply;
Adjust the wiring, increase the cross-sectional area of the conductor or shorten the length of the conductor to reduce the internal resistance;
Replace the diode with a small switching voltage drop;
Reduce the filter inductance or the internal resistance of the inductance
