Patent ID: 11870430
Assignee: MICROTERA SEMICONDUCTOR (GUANGZHOU) CO., LTD.
Field: Basic communication processes (Electrical engineering)
Classification: CPC H | IPC H

Claim 0:
1. An over-current protection circuit for composite transistor devices, connected between an input terminal and a load, comprising:
a control-terminal voltage-generation module, wherein an output voltage of the control-terminal voltage-generation module varies with an input voltage of the control-terminal voltage-generation module when driven by a first voltage, wherein the output voltage of the control-terminal voltage-generation module serves as a control-terminal voltage;
a composite transistor device, connected between the control-terminal voltage-generation module and the load, configured to conduct in response to the control-terminal voltage and a second voltage to generate an output current flowing through the load; and
an over-current protection module, connected between the composite transistor device and the load, wherein when the output current of the composite transistor device exceeds a preset limit, a clamping voltage is applied to the composite transistor device by the over-current protection module, to limit a current flowing through the composite transistor device, thereby limiting the output current of the composite transistor device,
wherein the composite transistor device comprises: a first transistor and a second transistor, wherein a control terminal of the first transistor is connected to the control-terminal voltage-generation module and the over-current protection module, wherein a first terminal of the first transistor is connected to the over-current protection module, wherein a second terminal of the first transistor is connected to a control terminal of the second transistor, wherein a first terminal of the second transistor is connected to the second voltage, wherein a second terminal of the second transistor is connected to the load, wherein the second terminal of the first transistor is further connected to the second voltage through a first resistor.