Integrated Circuit with Reverse Current Protection and Power Disconnect Detection

Abstract

An integrated circuit (IC) includes a switching transistor, a gate drive circuit, a current sensing circuit, a voltage drop regulation circuit, and a charge discharge circuit. The switching transistor is connected between the input port and the output port of the IC, and receives an input signal from a power supply and supplies the input signal to the output port as an output signal. A current sensing circuit detects the current flowing through the switching transistor. The gate drive circuit uses the control signal to drive the switching transistor. When the current through the switching transistor is low, the voltage drop regulation circuit is activated. A voltage drop regulation circuit controls the control signal to increase the voltage across the switching transistor. When the power supply is disconnected, the charge discharge circuit transfers excess charge from the input terminal of the IC to ground.

Description

technical field [0001] The invention relates to an integrated circuit, in particular to a load switch of the integrated circuit. Background technique [0002] Load switches are used in electronic circuits to connect or disconnect a power source to or from a load. Load switches are commonly used in battery charging circuits to charge a battery connected as a load. Typically, a load switch has an input port for receiving an input signal from a power source and an output port for connection to a battery. The load switch provides an input signal as an output signal to the battery through an output port to charge the battery. Load switches consist of transistors connected between input and output ports. When the power supply is disconnected and the load switch is still active, it has a very low resistance, on the order of tens of milliohms. This resistance is called "ON resistance". Because of this low "on resistance," the battery will supply a negative current to the load s...

AI Technical Summary

Problems solved by technology

Thus, it is difficult to determine the disconnection status between the power source and the load

Further, due to the small voltage difference between the input port and the output port, the transistors of the current sensing circuit are not easily matched with each other, which will reduce the accuracy of the current sensing circuit

Therefore, it is inaccurate and difficult to detect the negative current through the current sensing circuit

In addition, the current sensing circuit cannot accurately detect the current level of the input signal when the current level of the input signal is lower than a threshold

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