What is DC (Direct Current)? It represents a DC power source such as a dry battery or a car battery. The 220V power supply for home use is AC power supply (AC). If a converter can convert a DC voltage (3.0V) to another DC voltage (1.5V or 5.0V), we call this converter a DC-DC converter, or switching power supply or switching regulator.
A: DC-DC converters generally consist of control chips, inductors, diodes, transistors, and capacitors. When discussing the performance of a DC-DC converter, it is not possible to judge the merits of the control chip alone. The characteristics of the components of the peripheral circuit and the wiring pattern of the substrate can change the performance of the power circuit. Therefore, a comprehensive judgment should be made.
B: Modulation method
1: PFM (pulse frequency modulation method)
The switching pulse width is fixed, and the output voltage is stabilized by changing the pulse output time.
2: PWM (Pulse Width Modulation)
The switching pulse frequency is fixed. By changing the pulse output width, the output voltage stabilizes.
C: Generally, the performance of DC-DC converters using two different modulation methods, PFM and PWM, differs as follows.
PWM frequency, PFM duty ratio selection method.
Previous: Classification of inverter power