Q.3 Why MOSFET is used in buck-boost converter?

MOSFETs are used in buck-boost converters for several reasons:

1. High Switching Speed: MOSFETs have a high switching speed, which is crucial for the efficient operation of buck-boost converters. The faster the switch, the less energy is wasted in the transition from on to off state and vice versa.

2. Low On-Resistance: MOSFETs have a low on-resistance, which means they dissipate less power when they are in the on state. This improves the efficiency of the converter.

3. Voltage Control: MOSFETs are voltage-controlled devices. This means that the gate voltage controls the current flow through the device. This feature makes it easier to control the output voltage of the converter.

4. High Input Impedance: MOSFETs have a high input impedance, which means they draw very little gate current. This makes it easier to drive the gate and reduces the power required to control the switch.

5. Thermal Stability: MOSFETs are thermally stable, which means they can handle high temperatures without degrading in performance. This is important in power electronics applications where devices can get hot.

6. Size and Cost: MOSFETs are smaller and cheaper than other types of switches, such as bipolar junction transistors (BJTs). This makes them a cost-effective choice for buck-boost converters.