Oscillation-Based Test in Mixed-Signal Circuits

Contents......Page 7
Preface......Page 12
1.1.1 Point of origin: Early OBT......Page 15
1.1.2 Evolution of the OBT concept......Page 20
1.1.3 Critical analysis of the OBT concept......Page 22
1.2 The OBT Oscillator......Page 24
1.2.1 Direct approach: classical linear oscillator......Page 25
1.2.2 Second approach: oscillator using non-linear methods......Page 38
1.2.3 Proposed approach: amplitude \ncontrolled by limitation......Page 45
1.3.1 The oscillator......Page 52
1.3.2 General circuit modifications......Page 53
1.3.4 Requiring more test information......Page 55
1.3.5 Characterizing the test oscillator......Page 56
1.3.6 Characterizing the test interpretation......Page 57
1.3.7 The test process......Page 58
1.4 Summarizing the New OBT Concept......Page 60
2. MATHEMATICAL REVIEW OF NON-LINEAR OSCILLATORS......Page 63
2.1 Framework......Page 64
2.2 The Describing Function Method......Page 65
2.2.1 A General Describing-Function for Piecewise-linear Elements......Page 69
2.2.2 On the use of the DF method in oscillators......Page 72
2.2.3 Convergent Equilibrium: Steady Oscillation Mode......Page 75
2.3.1 Determining the oscillation parameters......Page 77
2.3.2 Describing-Function limitations......Page 81
2.4.1 First proposed method......Page 89
2.4.2 A graphical method for a particular type of nonlinearities......Page 98
2.5 Summary......Page 108
3.1 Feasible OBT Strategy in Discrete-time Filters......Page 110
3.1.1 Oscillation solutions for a generic filter......Page 112
3.1.2 Oscillation solutions for the biquadratic case......Page 118
3.1.3 A simple Non-Linear Block......Page 123
3.1.4 Oscillation Conditions......Page 124
3.2 Application to a Particular Biquad Structure......Page 130
3.2.1 Properties of the FL-Biquad......Page 132
3.2.2 Applying the OBT technique to the FL-biquad......Page 138
3.3 A Generic OBT Oscillator......Page 150
3.3.1 Conclusions extracted by the simplified results......Page 152
3.3.2 Conclusions extracted by the no-simplified results......Page 154
3.3.4 Guidelines to implement a generic OBT scheme......Page 155
3.4 Summary......Page 168
4. OBT METHODOLOGY FOR DISCRETE-TIMEΣΔ MODULATORS......Page 170
4.1.1 Basic approach: forcing oscillations using local extra feedback loops......Page 171
4.1.2 Practical OBT scheme in low-pass 2nd-order ΣΔ modulators......Page 178
4.1.3 Fault Analysis......Page 180
4.1.4 Fault Detection......Page 181
4.1.5 Extension to High-order Architectures......Page 184
4.2.1 Background......Page 187
4.2.2 Basic OBT approach: forcing oscillations around the notch frequency......Page 189
4.2.3 Practical OBT scheme: downsizing the oscillation frequency......Page 194
4.2.4 Structural Test and Fault Analysis......Page 197
4.2.5 Fault Detection......Page 200
4.2.6 Extension to Higher order structures......Page 204
4.3 Practical OBT Scheme for any Type of Modulators......Page 205
4.3.1 Theoretical Normalized Oscillation Parameters......Page 207
4.3.2 Fault Coverage considerations......Page 213
4.4 Summary......Page 215
5.1 A Specific Circuit......Page 217
5.2 Some Practical Examples......Page 221
5.3 Fault Coverage Considerations......Page 226
5.4 Oscillator Modelling Accuracy......Page 229
5.5 DTMF Biquad Validation......Page 231
5.2 Test Quality......Page 235
5.6 Summary......Page 243
6. PRACTICAL REGARDS FOR OBT-OBIST IMPLEMENTATION......Page 244
6.1 Demonstrator Macrocell......Page 246
6.2 Applying the OBT-OBIST Methodology to the DTMF Macrocell......Page 251
6.2.1 Biquad-Level Test......Page 253
6.2.2 System-Level Test......Page 255
6.2.3 A modified System Architecture......Page 261
6.2.4 An alternative implementation......Page 264
6.2.5 Cells adaptation for OBIST implementation......Page 268
6.2.6 Start-up problem......Page 276
6.2.7 The DTMF integrated prototype......Page 280
6.3.1 Using a Frequency Measurement Counter......Page 283
6.3.2 Using a Peak Detector to determine the amplitude......Page 285
6.3.3 Using a low-accuracy ΣΔ modulator......Page 286
6.4 Electrical Simulation Results in the OBIST Mode......Page 293
6.5.1 Digital Detection algorithm......Page 295
6.5.3 Simple Frequency Measurement Counter Block......Page 296
6.6 DTMF/OBIST Operation Modes Description......Page 298
6.6.1 OBIST Mode description......Page 301
6.6.2 Test Strategy Comparison......Page 303
6.7 Summary......Page 305
7.1 Introduction......Page 307
7.2 First Experimental Demonstrator......Page 308
7.2.1 Programmable biquad and fault programming......Page 309
7.2.2 Experimental results......Page 310
7.2.3 On-chip evaluation......Page 334
7.3 Second Circuit Demonstrator: DTMF Receiver......Page 337
7.3.1 Floor-Planning and Chip......Page 338
7.3.2 DTMF Operation Modes......Page 339
7.4 Summary......Page 368
Appendix 2.A......Page 369
Appendix 5.A......Page 384
Appendix 5.B......Page 408
Appendix 5.C......Page 419
Appendix 6.A......Page 422
Appendix 7.A......Page 426
References......Page 446