US 6,667,651 B2 · Voltage supply circuit and control method of the same

Abstract

A voltage supply circuit capable of dealing with an abrupt change of a load by controlling an amount of increase of a power source voltage to be larger than an amount of reduction, supplying a stable operating power source voltage, and realizing lower power consumption while maintaining normal operation of a semiconductor integrated circuit is provided. By providing a replica circuit 20, detecting a delay time of a critical path of an LSI 10, comparing a delay time detected by a control circuit 50 with a predetermined reference value, performing control to raise a voltage VDD supplied to the LSI 10 when the delay time is larger than the reference value as a result of the comparison and to lower the voltage VDD supplied to the LSI 10 when the delay time is smaller than the reference value, and making the amount of increase at the time of raising the supplied voltage larger than the amount of reduction at the time of lowering it, when the supplied voltage VDD becomes smaller than the reference value, it can be quickly restored to be larger than the reference value, the time when operating error of the LSI 10 may occur can be greatly shortened, and the operational stability of the voltage supply circuit can be improved.

Claims23

Dependent claims

A voltage supply circuit comprising:

a functional circuit for performing predetermined processing in accordance with an input signal at an operating speed based on a power source voltage supplied and outputting a processing result after a predetermined delay time from when said input signal is received,
a delay detection circuit for detecting a delay time of said functional circuit,
a control circuit for outputting a control signal to control said power source voltage to raise or lower it in accordance with a delay time detected by said delay detection circuit and to make an amount of change at the time of raising said power source voltage larger than an amount of change at the time of lowering it, and
a voltage generation circuit for generating a voltage in accordance with said control signal and supplying it as said power source voltage to said functional circuit.

1 more element

A voltage supply circuit comprising

a functional circuit for performing predetermined processing in accordance with an input signal at an operating speed based on a power source voltage supplied and outputting a processing result after a predetermined delay time from when said input signal is received,
a replica circuit having almost the same delay time as that of a critical path of said functional circuit,
a delay detection circuit for detecting a delay time of said replica circuit,
a control circuit for finding a power source voltage by which a delay time of the replica circuit satisfies a predetermined reference value in accordance with a delay time detected by said delay detection circuit, finding a power source voltage to be supplied to said functional circuit based on a relationship of a power source voltage of said replica circuit and a power source voltage of said functional circuit under the same operating conditions, and outputting a control signal in accordance with the power source voltage, and
a voltage generation circuit for generating a voltage in accordance with said control signal and supplying it as said power source voltage to said functional circuit.

2 more elements

A voltage supply circuit comprising

a functional circuit for performing predetermined processing in accordance with an input signal at an operating speed based on a power source voltage supplied and outputting a processing result after a predetermined delay time from when said input signal is received,
a delay detection circuit for detecting a delay time of said functional circuit,
a control circuit for obtaining an amount of change of a delay time corresponding to an amount of change of said power source voltage in accordance with a delay time detected by said delay detection circuit, deducing production conditions based on information regarding a power source voltage and a delay time under different production conditions found in advance, finding a power source voltage to be supplied to said functional circuit under the deduced production conditions, and outputting a control signal in accordance with the power source voltage, and
a voltage generation circuit for generating a voltage in accordance with said control signal and supplying it as said power source voltage to said functional circuit.

1 more element

Dependencies are inferred from the claim text.

Voltage supply circuit and control method of the same

Life of this patent

Voltage supply circuit and control method of the same

Life of this patent

Abstract

Claims23