The switching power supply is roughly composed of the main circuit
It is composed of control circuit, detection circuit and auxiliary power supply.
1. Main circuit
Impulse current limiting: limit the impulse current at the input side at the moment of power on.
Input filter: its function is to filter the clutter existing in the power grid and prevent the clutter generated by the machine from being fed back to the power grid.
Rectification and filtering: the AC power supply of the power grid is directly rectified into smoother DC power.
Inverter: convert the rectified DC into high-frequency AC, which is the core of high-frequency switching power supply.
Output rectification and filtering: provide stable and reliable DC power supply according to load requirements.
2. Control circuit
On the one hand, samples are taken from the output end and compared with the set value, and then the inverter is controlled to change its pulse width or pulse frequency to stabilize the output. On the other hand, according to the data provided by the test circuit and identified by the protection circuit, the control circuit is provided to carry out various protection measures for the power supply.
3. Detection circuit
Provide various parameters and instrument data in operation in the protection circuit.
4. Auxiliary power supply
The software (remote) startup of the power supply is realized to supply power for the protection circuit and control circuit (PWM and other chips).
