A bidirectional power switch, or BPS, is an active device constructed using MOSFETs or IGBTs that allows bidirectional current flow when powered up and prevents bidirectional voltage flow when powered down.

Characteristics

1. Low on-state resistance

2. Low static current

3. High voltage withstand capability

4. High-temperature operating capability, etc.

It has the function of bidirectional conduction, which can realize bidirectional power switch control. As shown in the figure below,

A: Apply positive voltage

B: Apply negative voltage

The structure of a bidirectional switch (BPS) usually consists of two MOSFETs: one for forward switching and one for reverse switching.

Simply changing the polarity of the voltage can reverse the switch action

(Interchangeable between points A and B)

In the forward switching state, the forward MOSFET conducts, and the reverse MOSFET is off;

In the reverse switching state, the reverse MOSFET conducts, and the forward MOSFET is off.

When both control signals are low, both MOSFETs are in the off state. There is no current flowing through the circuit at this time, and it is in an open circuit state.

When either control signal is high, the corresponding MOSFET is in the on state. At this time, the circuit is in a path state with current flowing through the conducting MOSFET.

When both control signals are high, both MOSFETs are in the on state. At this time, the path through which current flows in the circuit is cut off, and it is in an open circuit state.

Bidirectional switches (BPS) have the following functions:

1. Due to their characteristics, they can realize bidirectional (positive and negative) power switch control;

2. They have low on-state resistance to reduce power consumption and improve load regulation;

3. They have sufficient high-voltage and high-temperature operating capabilities to withstand use in high-temperature environments and high-voltage scenarios.

4. They have low static current, which can extend battery life;

Protection functions: BPS also includes overvoltage protection, overcurrent protection, overtemperature protection, etc.

In MOSFETs, BPS is typically used in power management circuits.

Such as battery protection circuits, power switching circuits, etc. Similarly, bidirectional switches (BPS) can achieve bidirectional power switch control, protect circuits from damage due to overvoltage, overcurrent, etc., and improve the reliability and stability of the circuit.