Heating situation of low-voltage MOS diodes

Heating situation of low-voltage MOS diodes

The general heating conditions of pipes are as follows:

The problem with circuit design is to make the MOS transistor operate in a linear state, rather than in a switching circuit state. This is also a reason for the heating of MOS diodes. If N-MOS is used as a switch, the G-level voltage needs to be several volts higher than the power supply in order to fully conduct, while P-MOS is the opposite. If the voltage drop is too high due to incomplete opening, the success rate will be consumed. The equivalent DC impedance is relatively high, and the voltage drop will increase, so U * I will also increase. The loss means heating. This is the most taboo mistake in designing circuits.

2. The frequency is too high, mainly due to sometimes excessive pursuit of volume, which leads to an increase in frequency and increased losses on MOS diodes, resulting in increased heating.

3. Insufficient heat dissipation design, high current, nominal current value of MOS transistor, generally requiring good heat dissipation to achieve. So if the ID is less than the maximum current, it may also cause severe heat generation and require sufficient auxiliary heat dissipation fins.

4. The selection of MOS diodes was incorrect, the power judgment was incorrect, and the internal resistance of MOSS diodes was not fully considered, resulting in an increase in switch impedance.