Abstract: A method of testing an integrated circuit device, that operates at a clock frequency and that has at least one scan chain that includes a plurality of registers separated by combinatorial logic, includes establishing a respective scan chain test pattern for testing the scan chain where the scan chain test pattern includes a respective bit for each register in the plurality of registers of the scan chain, determining in advance a respective timing delay for each pair of adjacent registers in the scan chain, and, within a single clock period of the clock frequency, applying, in parallel, each bit of the respective scan chain pattern to a respective register in the plurality of registers in the scan chain, each bit of the respective scan chain pattern being applied to its respective register at a respective temporal offset, within the single clock period, based on the respective timing delay.

Abstract: An integrated circuit device includes a plurality of cells or modules. Each respective one of the cells or modules consumes leakage power, and the amount of leakage power consumed by a respective one of the cells or modules varies depending on states of its inputs. Scan-chain circuitry is configured to propagate through the integrated circuit device, on entry of the integrated circuit device to a low-power mode, a scan-chain pattern created in advance, to apply, to each respective cell or module in the low-power mode, a set of inputs that results in a respective low-power state with reduced leakage power. Creating the scan chain pattern includes identifying respective ones of the cells or modules as having the highest leakage power consumption, and a respective combination of inputs to place each of those the cells or modules in a respective low-power state.