Semiconductor integrated circuit
AssigneeRohm Co., Ltd.
InventorYuji Saegusa
Life of this patent
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Abstract
An output OUT is coupled to a load. A high-side transistor MH is arranged such that its source is coupled to a power supply line, and such that its drain is coupled to an output terminal OUT. A first OCP circuit compares a first current detection signal ICS1 that corresponds to a current ISRC that flows through the high-side transistor MH with a first threshold value IOCP having a positive correlation with a power supply voltage VDD of a power supply line, and generates a first OCP signal SOCP that indicates the comparison result. A driving circuit latch-stops the driving operation of the high-side transistor MH according to the first OCP signal SOCP.
Claims15
A semiconductor integrated circuit comprising:
- an output terminal to be coupled to a load;
- a high-side transistor structured as a PMOS transistor having a source coupled to a power supply line and a drain coupled to the output terminal;
- a first overcurrent protection circuit structured to compare a first current detection signal that corresponds to a current that flows through the high-side transistor with a first threshold value having a positive correlation with a power supply voltage of the power supply line, and to generate a first overcurrent protection signal that indicates a comparison result;
- and
- a driving circuit structured to turn off the high-side transistor according the first overcurrent protection signal such that the first threshold value becomes higher when the power supply voltage becomes higher.
A protection method for an audio amplifier, wherein the audio amplifier comprises a push-pull output stage comprising a high-side transistor and a low-side transistor,
- and wherein the protection method comprises:
- latch-stopping the audio amplifier when a source current that flows through the high-side transistor exceeds a first threshold value;
- and
- adjusting the first threshold value such that it has a positive correlation with respect to a power supply voltage to be supplied to the audio amplifier and the first threshold value becomes higher when the power supply voltage becomes higher.
Dependencies are inferred from the claim text.