19_pdfsam_VLSI TEST PRINCIPLES & ARCHITECTURES -...

xviii Contents
11.1.1.2 Large Range of Circuits . . . . . . . . . . . . . . 621
11.1.1.3 Nonlinear Characteristics . . . . . . . . . . . . . 621
11.1.1.4 Feedback Ambiguity . . . . . . . . . . . . . . . . 622
11.1.1.5 Complicated Cause–Effect Relationship . . . . . 622
11.1.1.6 Absence of Suitable Fault Model . . . . . . . . . 622
11.1.1.7 Requirement for Accurate Instruments for
Measuring Analog Signals . . . . . . . . . . . . . 623
11.1.2 Analog Defect Mechanisms and Fault Models . . . . . . . . 623
11.1.2.1 Hard Faults . . . . . . . . . . . . . . . . . . . . . . 625
11.1.2.2 Soft Faults . . . . . . . . . . . . . . . . . . . . . . 625
11.2 Analog Circuit Testing . . . . . . . . . . . . . . . . . . . . . . . . . . 627
11.2.1 Analog Test Approaches . . . . . . . . . . . . . . . . . . . . 627
11.2.2 Analog Test Waveforms . . . . . . . . . . . . . . . . . . . . . 629
11.2.3 DC Parametric Testing . . . . . . . . . . . . . . . . . . . . . 631
11.2.3.1 Open-Loop Gain Measurement . . . . . . . . . . 632
11.2.3.2 Unit Gain Bandwidth Measurement . . . . . . . 633
11.2.3.3 Common Mode Rejection Ratio Measurement . 634
11.2.3.4 Power Supply Rejection Ratio Measurement . . 635
11.2.4 AC Parametric Testing . . . . . . . . . . . . . . . . . . . . . 635
11.2.4.1 Maximal Output Amplitude Measurement . . . . 636
11.2.4.2 Frequency Response Measurement . . . . . . . . 637
11.2.4.3 SNR and Distortion Measurement . . . . . . . . 639
11.2.4.4 Intermodulation Distortion Measurement . . . . 641
11.3 Mixed-Signal Testing . . . . . . . . . . . . . . . . . . . . . . . . . . . 641
11.3.1 Introduction to Analog–Digital Conversion