Power supply phase doubling system

A power supply phase doubling system, comprising:

• a pulse width modulation controller, configured to output a pulse width modulation signal;
• a first phase doubling chip, coupled to the pulse width modulation controller, operated at a power supply voltage and having a first pulse width modulation output pin, configured to generate a first control signal and a second control signal according to the pulse width modulation signal, and generating a first output signal according to the first control signal;
• and
• a second phase doubling chip, coupled to the first phase doubling chip, operated at the power supply voltage and having a second pulse width modulation output pin, and configured to generate a second output signal according to the second control signal,
• wherein the first phase doubling chip and the second phase doubling chip are respectively switched between a master mode and a slave mode according to a voltage level of the first pulse width modulation output pin and a voltage level of the second pulse width modulation output pin.