公开(公告)号：US20210088582A1

公开(公告)日：2021-03-25

申请号：US16582758

申请日：2019-09-25

Applicant: Advanced Micro Devices, Inc.

Inventor： Venkat Krishnan Ravikumar ,  Nathan Linarto ,  Wen Tsann Lua ,  Abel Tan Yew Hong ,  Shei Lay Phoa ,  Gopinath Ranganathan ,  Jiann Minn Chin

IPC: G01R31/28 ,  G01R23/17 ,  G01R29/08

Abstract: An optic probe is used to measure signals from a device under test. The optic probe is positioned at a target probe location within a cell of the device under test, the cell including a target net to be measured and a plurality of non-target nets. A test pattern is applied to the cell with the optic probe a laser probe (LP) waveform is obtained in response. A target net waveform is extracted from the LP waveform by: (i) simulating a combinational logic analysis (CLA) cross-talk waveform to model cross-talk from selected non-target nets by simulating an optical response of the cell to the test pattern with the target net masked; (ii) estimating a cross-talk weight; and (iii) determining a target net waveform by weighting the CLA cross-talk waveform according to the cross-talk weight and subtracting the weighted CLA cross-talk waveform from the LP waveform.

公开(公告)号：US20200284837A1

公开(公告)日：2020-09-10

申请号：US16296614

申请日：2019-03-08

Applicant: Advanced Micro Devices, Inc.

Inventor： Venkat Krishnan Ravikumar ,  Wen Tsann Lua ,  Gopinath Ranganathan ,  Yi Xuan Seah ,  Shei Lay Phoa ,  Nathan Linarto ,  Jiann Min Chin

IPC: G01R31/311

Abstract: A control system for placing an optic probe includes a receiver circuit that receives reflected light produced from the optic probe and provides a laser probe (LP) waveform of the reflected light in response to an activation of a trigger signal. A combinational logic analysis (CLA) processor provides a CLA waveform in response to simulating an optical response at a target location on a surface of a cell of a device under test to a test pattern. A test controller receives the CLA waveform and the LP waveform, and has a first output for providing the trigger signal, a second output for providing the test pattern, and a third output for providing a position signal. The test controller updates the position signal to move the optic probe closer to the target location according to a degree of fit between the LP waveform and the CLA waveform.

公开(公告)号：US10768225B1

公开(公告)日：2020-09-08

申请号：US16296614

申请日：2019-03-08

Applicant: Advanced Micro Devices, Inc.

Inventor： Venkat Krishnan Ravikumar ,  Wen Tsann Lua ,  Gopinath Ranganathan ,  Yi Xuan Seah ,  Shei Lay Phoa ,  Nathan Linarto ,  Jiann Min Chin

IPC: G01R31/311

Abstract: A control system for placing an optic probe includes a receiver circuit that receives reflected light produced from the optic probe and provides a laser probe (LP) waveform of the reflected light in response to an activation of a trigger signal. A combinational logic analysis (CLA) processor provides a CLA waveform in response to simulating an optical response at a target location on a surface of a cell of a device under test to a test pattern. A test controller receives the CLA waveform and the LP waveform, and has a first output for providing the trigger signal, a second output for providing the test pattern, and a third output for providing a position signal. The test controller updates the position signal to move the optic probe closer to the target location according to a degree of fit between the LP waveform and the CLA waveform.

公开(公告)号：US11125815B2

公开(公告)日：2021-09-21

申请号：US16585963

申请日：2019-09-27

Applicant: Advanced Micro Devices, Inc.

Inventor： Venkat Krishnan Ravikumar ,  Jiann Min Chin ,  Joel Yang Kwang Wei ,  Pey Kin Leong

IPC: G01R31/28 ,  G01R31/265 ,  G01R31/311 ,  G01R23/17 ,  G01R29/08

Abstract: A reconfigurable optic probe is used to measure signals from a device under test. The reconfigurable optic probe is positioned at a target probe location within a cell of the device under test. The cell including a target net to be measured and non-target nets. A test pattern is applied to the cell and a laser probe (LP) waveform is obtained in response. A target net waveform is extracted from the LP waveform by: i) configuring the reconfigurable optic probe to produce a ring-shaped beam having a relatively low-intensity region central to the ring-shaped beam; (ii) re-applying the test pattern to the cell at the target probe location with the relatively low-intensity region applied to the target net and obtaining a cross-talk LP waveform in response; (iii) normalizing the cross-talk LP waveform; and (iv) determining a target net waveform by subtracting the normalized cross-talk LP waveform from the LP waveform.

公开(公告)号：US11143700B2

公开(公告)日：2021-10-12

申请号：US16582758

申请日：2019-09-25

Applicant: Advanced Micro Devices, Inc.

Inventor： Venkat Krishnan Ravikumar ,  Nathan Linarto ,  Wen Tsann Lua ,  Abel Tan Yew Hong ,  Shei Lay Phoa ,  Gopinath Ranganathan ,  Jiann Minn Chin

IPC: G01R31/28 ,  G01R31/265 ,  G01R31/311 ,  G01R31/01 ,  G01R23/17 ,  G01R29/08

Abstract: An optic probe is used to measure signals from a device under test. The optic probe is positioned at a target probe location within a cell of the device under test, the cell including a target net to be measured and a plurality of non-target nets. A test pattern is applied to the cell with the optic probe a laser probe (LP) waveform is obtained in response. A target net waveform is extracted from the LP waveform by: (i) simulating a combinational logic analysis (CLA) cross-talk waveform to model cross-talk from selected non-target nets by simulating an optical response of the cell to the test pattern with the target net masked; (ii) estimating a cross-talk weight; and (iii) determining a target net waveform by weighting the CLA cross-talk waveform according to the cross-talk weight and subtracting the weighted CLA cross-talk waveform from the LP waveform.

公开(公告)号：US20210096174A1

公开(公告)日：2021-04-01

申请号：US16585963

申请日：2019-09-27

Applicant: Advanced Micro Devices, Inc.

Inventor： Venkat Krishnan Ravikumar ,  Jiann Min Chin ,  Joel Yang Kwang Wei ,  Pei Kin Leong

IPC: G01R31/28 ,  G01R23/17 ,  G01R29/08

Abstract: A reconfigurable optic probe is used to measure signals from a device under test. The reconfigurable optic probe is positioned at a target probe location within a cell of the device under test. The cell including a target net to be measured and non-target nets. A test pattern is applied to the cell and a laser probe (LP) waveform is obtained in response. A target net waveform is extracted from the LP waveform by: i) configuring the reconfigurable optic probe to produce a ring-shaped beam having a relatively low-intensity region central to the ring-shaped beam; (ii) re-applying the test pattern to the cell at the target probe location with the relatively low-intensity region applied to the target net and obtaining a cross-talk LP waveform in response; (iii) normalizing the cross-talk LP waveform; and (iv) determining a target net waveform by subtracting the normalized cross-talk LP waveform from the LP waveform.