Operating pulsed latches on a variable power supply

An apparatus for operating pulsed latches on a variable power supply, the apparatus comprising computer memory having disposed within it computer program instructions that, when executed, cause the apparatus to carry out the steps of:

• turning on a first power rail powering a first latch of an integrated circuit, wherein the first latch is a pulsed latch, and wherein the first latch is a scan-only latch;
• turning on a second power rail powering a second latch of the integrated circuit, wherein the second latch is operatively coupled to the first latch;
• performing a scan operation using the first latch and the second latch;
• turning off the first power rail powering the first latch;
• and
• responsive to completing the scan operation using the first latch and the second latch, performing a functional operation using the second latch, wherein the first power rail powering the first latch is off during the functional operation.

A computer program product for operating pulsed latches on a variable power supply, the computer program product disposed upon a non-transitory computer readable medium, the computer program product comprising computer program instructions that, when executed, cause a computer to carry out the steps of:

• turning on a first power rail powering a first latch of an integrated circuit, wherein the first latch is a pulsed latch, and wherein the first latch is a scan-only latch;
• turning on a second power rail powering a second latch of the integrated circuit, wherein the second latch is operatively coupled to the first latch;
• performing a scan operation using the first latch and the second latch;
• turning off the first power rail powering the first latch;
• and
• responsive to completing the scan operation using the first latch and the second latch, performing a functional operation using the second latch, wherein the first power rail powering the first latch is off during the functional operation, wherein the first latch and the second latch are directly connected such that no latch is between the first latch and the second latch.