Marvell Asia Pte., Ltd.

Balaji Upputuri

Sreekanth G Pai

Kushal Kamal

Mallikarjunarao Thummalapalli

Umesh Prabhakar Hade

Scott Mack

A method of testing an integrated circuit device includes detecting a number of integrated clock gates (ICGs) in the device. Each ICG can stop clock propagation in a respective branch of a clock tree of the device. For each detected ICG, an ICG fanout (a number of digital inputs that the output of each ICG can feed) is compared with a threshold number of registers. When the ICG fanout is greater than the threshold number, it is determined whether a function-enable path of an existing ICG is timing-critical. When the function-enable path of the existing ICG is timing-critical, an additional ICG and a test point are inserted into the device as a clock input to the existing ICG. When the function-enable path of the existing ICG is not timing-critical, a test point and an AND-gate may be inserted in that function-enable path.

Method and apparatus for capture clock control to minimize toggling during testing

A method of scan-chain testing of an integrated circuit device having a plurality of respective scan-chain paths, at least some of the respective scan-chain paths being designated as having resource constraints, includes propagating a respective scan-chain data pattern through each of the respective scan-chain paths, and gating each respective scan-chain path designated as having resource constraints, to reduce a rate of scan-chain data propagation through the respective scan-chain path, without gating any scan-chain path not designated as having resource constraints. Scan-chain paths may be designated as having resource constraints because of high power consumption or data congestion.

Power-sensitive scan-chain testing

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.

Method and apparatus for timing-annotated scan-chain testing using parallel testbench

A method of loading a data string into a Joint Test Action Group (JTAG) shift register is provided. The method includes determining whether the last bit of the data string is equal to one or zero. In response to determining that the last bit is equal to one, the method includes simultaneously setting each flip-flop of the shift register to one, identifying first data string loading bits by removing, from the data string, the last bit and any other bits in a continuous sequence of bits, including the last bit, that are each equal to one, and sequentially loading the identified first data string loading bits into the shift register. A testing apparatus for performing the method and an enhanced JTAG interface are also provided. The method, testing apparatus, and enchanced JTAG interface may reduce the number of clock cycles required to load the shift register.

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Ongole, India

Balaji Upputuri