| 摘要 |
A power supply protection and control method, comprising a short-circuit protection and control method, which implements protection control by using the following steps: step 1, a power supply is turned on, and a control IC is started; step 2, a soft-start module controls a feedback signal of a first input/output port to rise slowly from 0 V, the power supply is soft-started normally, and a duty cycle of a driving signal is increased slowly; step 3, after the soft-start of the power supply ends, a voltage detection module detects the feedback signal and compares the feedback signal with a preset reference voltage, and if the feedback signal is higher than the reference voltage, the voltage detection module outputs a short-circuit protection signal to a counting control module, and the flow enters step 4; otherwise, the short-circuit protection signal is not output, the power supply operates normally, the feedback signal is detected again, and power supply self-detection starts; step 4, the counting control module receives the short-circuit protection signal, starts to count detection delay time, and determines whether the duration of the short-circuit protection signal exceeds the detection delay time, and if yes, a shut-off signal is output to a driver to stop outputting the driving signal, the power supply is turned off, and the state of a control signal is inverted, and the flow enters step 5; otherwise, the flow returns to step 3; step 5, counting of short-circuit break time starts, and after the counting ends, the shut-off signal is deactivated, and the state of the control signal is inverted again; at this time, a narrow-pulse generator is triggered by an inversion edge of the control signal, the narrow-pulse generator outputs a narrow-pulse reset signal to the soft-start module, the soft-start state is reset, and the feedback signal is pulled down; step 6, after the narrow pulse duration ends, the narrow-pulse reset signal is inverted to the initial state, and the flow returns to step 2. The power supply protection and control method can avoid the problem of high power consumption after protection of the power supply is triggered, and meanwhile reduce the complexity of system design. |
