There are four modulation methods for socket and switching power supply


All electrical equipment needs to be modulated. The patch earphone socket is the same as the switching power supply. Flip the switch to summarize that there are four modulation methods for socket and switching power supply

1. Hybrid modulation. It is a combination of three and four methods. The switching cycle and pulse width are not fixed and can be adjusted. It includes PWM controller and PFM controller.

2. Pulse density modulation (PDM for short). Its characteristic is that the pulse width is a stable value, and the purpose of voltage stabilization is achieved by adjusting the number of pulses. It uses zero-voltage technology, which can significantly reduce the loss of power switch.

3. Pulse frequency modulation (PFM for short). Its characteristic is that the pulse width is a stable value, and the duty cycle is changed by adjusting the switching frequency to complete the purpose of voltage stabilization. At the center is the PFM controller. Pulse frequency modulation switching power supply is particularly suitable for portable devices. It can reduce the static current of the control chip under the conditions of low duty cycle and low frequency.

4. Pulse width modulation (PWM for short). Its characteristic is that the socket and switch cycle are stable values, and the duty cycle is changed by adjusting the pulse width to achieve the purpose of voltage stabilization. The center is PWM controller. Pulse width modulation socket and switching power supply are most widely used, and their duty cycle adjustment scale is large. PWM can also keep synchronization with the clock of the main system.