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CONTENTS PAGEINTRODUCTION 1FEEDBACK OSCILLATORS 1Loop Gain 1How Feedback Oscillators Work 2The Positive Reactance Oscillator 2QUARTZ CRYSTALS 3Crystal Parameters 3Equivalent Circuit 3Load Capacitance 4``Series' vs. ``Parallel' Crystals 4Equivalent Series Resistance 4Frequency Tolerance 5Drive Level 5CERAMIC RESONATORS 5Specifications for Ceramic Resonators 6OSCILLATOR DESIGNCONSIDERATIONS 6On-Chip Oscillators 6Crystal Specifications 6Oscillation Frequency 7Selection of CX1 and CX2 7Placement of Components 7Clocking Other Chips 7External Oscillators 8Gate Oscillators vs. Discrete Devices 10Fundamental vs. OvertoneOperation 11``Series' vs. ``Parallel' Operation 11CONTENTS PAGEMORE ABOUT USING THE ``ON-CHIP'OSCILLATORS 11Oscillator Calculations 11Start-Up Characteristics 13Steady-State Characteristics 15Pin Capacitance 16MCSÉ-51 Oscillator 16MCSÉ-48 Oscillator 16CONTENTS PAGEPre-Production Tests 19Troubleshooting Oscillator Problems 20APPENDIX A: QUARTZ AND CERAMICRESONATOR FORMULAS A-1APPENDIX B: OSCILLATOR ANALYSISPROGRAM B-1
