A power
adaptation circuit for outputting a power state
signal, which includes three switch elements, a
diode, three resistors and a
capacitor, wherein each switch element includes a first terminal, a second terminal and a At the third end, a
system power supply is grounded sequentially through the first
resistor and
capacitor, the first end of the first switching element is connected to the node between the first
resistor and the
capacitor, and is also connected to the
anode of the
diode, and the second end is connected to the second end through the first The two resistors are connected to a
backup power supply, and are also connected to the first terminal of the second switching element, the third terminal is grounded, the second terminal of the second switching element is grounded, and the third terminal is connected to the
system power supply through the third
resistor, and serves as the The output end of the power
adaptation circuit, the third end of the third switch element is used to receive a power-on
signal, the second end is grounded, and the third end is connected to the
cathode of the
diode. The above power adapter circuit can effectively solve the problem of incompatibility between the computer
motherboard and the power supply.