Patent ID: 7605575

Claim:
A voltage-supply circuit, comprising: a regulator circuit, which is connected between a first supply-voltage feed line and a second supply-voltage feed line, and which is formed to regulate, based on a first supply voltage present on the first supply-voltage feed line, a second supply voltage present on the second supply-voltage feed line, the regulator circuit being formed to provide a supply current to the second supply-voltage feed line, wherein the regulator circuit comprises a regulation transistor which is connected between the first supply-voltage feed line and the second supply-voltage feed line to provide the supply current to the second supply-voltage feed line; an operating-point determiner, which is formed to determine, based on information that is a measure for the supply current, whether the regulator circuit is at a low operating point at which the supply current is below a determined value, wherein at a supply current below the determined value the second supply voltage temporarily falls in amount below a predetermined permissible minimum voltage value below which a reliable operation of a circuit provided with the second supply voltage is not guaranteed if the current present on the second supply-voltage feed line rises by a predetermined current amount within a predetermined period; and a preventer, which is formed to prevent, starting from the low operating point, a rise of the supply current by at least the predetermined current amount from occurring within the predetermined period.