Integrated circuit devices having power control logic that inhibits internal leakage current loss during sleep mode operation and method of operating same

An integrated circuit system, comprising:

• an integrated circuit chip;
• an internal functional logic circuit on said integrated circuit chip, said internal functional logic circuit having an active mode of operation and a power-saving sleep mode of operation which is initiated by the generation of a sleep mode request on or off said integrated circuit chip;
• an internal power control logic circuit on said integrated circuit chip that generates a power down signal in response to the sleep mode request;
• an active/sleep mode power supply pad that extends on said integrated circuit chip and is electrically coupled to said internal functional logic circuit;
• and
• power switching circuitry that is disposed external to said integrated circuit chip, is electrically connected to said active/sleep mode power supply pad and supplies power to or withholds power from said active/sleep mode power supply pad in response to the power down signal generated by said internal power control logic circuit.

A method of operating an integrated circuit device, comprising the steps of:

• operating first and second functional logic circuits internal to the integrated circuit device in respective power supplying modes during which power switching circuitry external to the integrated circuit device selectively supplies power to each of the first and second functional logic circuits;
• generating an active first sleep mode request signal internal to or external to the integrated circuit device;
• transferring an active first power down signal from the integrated circuit device to the power switching circuitry, in response to the active first sleep mode request signal;
• and
• switching the external power switching circuitry from a first power supplying mode to a first power withholding mode during which power is selectively withheld from the first functional logic circuit but not the second functional logic circuit, in response to the active first power down signal.

A method of operating an integrated circuit device, comprising the steps of:

• operating first and second functional logic circuits internal to the integrated circuit device in respective power supplying modes during which power switching circuitry external to the integrated circuit device selectively supplies power to each of the first and second functional logic circuits;
• generating an active first sleep mode request signal internal to or external to the integrated circuit device;
• transferring an active first power down signal from the integrated circuit device to the power switching circuitry, in response to the active first sleep mode request signal;
• and
• switching the external power switching circuitry from a first power supplying mode to a first power withholding mode during which power is selectively withheld from the first functional logic circuit but not the second functional logic circuit, in response to the active first power down signal;
• wherein said transferring step comprises generating a leading edge of the first power down signal in-sync with a leading edge of the first sleep mode request signal.

A method of operating an integrated circuit device, comprising the steps of:

• operating a first logic circuit internal to the integrated circuit device in an power saving mode during which power switching circuitry external to the integrated circuit device selectively supplies power to the first functional logic circuit;
• generating an active first sleep mode request signal internal to or external to the integrated circuit device;
• transferring an active first power down signal from the integrated circuit device to the power switching circuitry, in response to the active first sleep mode request signal;
• and
• switching the external power switching circuitry from a first power supplying mode to a first power withholding mode during which power is selectively withheld from the first functional logic circuit, in response to the active first power down signal.