System and method for testing and fault isolation of high density passive boards and substrates

US5402072A · kind A · utility

Assignee

• International Business Machines Corporation · US

Inventors

• Shinwu Chiang · Yorktown Heights, US
• Huntington W. Curtis · Chelsea, US
• Arthur E. Falls · Brookfield, US
• Arnold Halperin · Somers, US
• John P. Karidis · Ossining, US
• John D. Mackay · Sleepy Hollow, US
• Danny Wong · Parramatta, AU
• Ka-Chiu Woo · Hopewell Junction, US
• Li-Cheng Richard Zai · Taipei, TW

Key dates

• Filing date: Feb 28, 1992
• Grant date: Mar 28, 1995
• Expiry date: Feb 28, 2012

Classification

• Technology area (CPC G): Physics
• CPC primary: G01R31/2805
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

Apparatus and method are disclosed for performing testing and fault isolation of high density passive boards (e.g. unpopulated circuit boards) and substrates. Using a small number of moving probes, simultaneous network resistance and network capacitance measurements may be performed. Thus, test time is minimized by eliminating the need for electrical switching and/or excessive probe movement during the test of a normal circuit board network. Simultaneous network capacitance and network leakage measurement are also achieved using phase-sensitive detection. Dual-frequency measurement techniques allow the measurement of both the capacitance value and resistance value of a leakage path between a network being measured and an unknown network. Any leakage resistance between a network under test and ground or power planes within the circuit board may also be determined from the measurements. Simultaneous independent net-to-plane capacitance characterization is also achieved using signals of mutually independent frequencies accompanied by minimal signal processing. Thus, improved defect detection capabilities are obtained.