| US 7,602,162 B2 | ||
| Voltage regulator with over-current protection | ||
| Nitin Bansal, Gurgaon (India); Rupesh Khare, Ghaziabad (India); and Amit Katyal, Ghaziabad (India) | ||
| Assigned to STMicroelectronics Pvt. Ltd., Greater Noida (India) | ||
| Filed on Nov. 27, 2006, as Appl. No. 11/604,655. | ||
| Claims priority of application No. 3198/DEL/2005 (IN), filed on Nov. 29, 2005. | ||
| Prior Publication US 2007/0194768 A1, Aug. 23, 2007 | ||
| Int. Cl. G05F 1/573 (2006.01) | ||
| U.S. Cl. 323—277 | 14 Claims |
| 1. A circuit that receives an input voltage at an input terminal and provides a regulated output voltage at an output node,
comprising:
an error circuit responsive to a difference between a predetermined reference voltage and a voltage which is a function of
the output voltage to produce an error signal;
a current driver circuit, responsive to said error signal to adjust a current to the output node and reduce the error signal;
a current sensing circuit coupled to the current driver circuit at its input terminal to sense the output current and coupled
to a current sink device which sinks a current output from the current sensing circuit; and
a feedback circuit coupled to the output of said current sensing circuit and providing a feedback control signal to control
the current to the output node,
wherein said feedback circuit comprises an NMOS transistor with its gate connected to the output of said current sensing circuit
and its drain connected to the input of said current driver circuit, the feedback NMOS transistor responding to the feedback
control signal to sink current from the error signal output from the error circuit and input to the current driver circuit.
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