MT1198F

Evaluation of ceramic resonator oscillation characteristics This paper is prepared to explain characteristics, test methods, and glossary of the oscillation circuit composed of a CMOS inverter and ceramic resonator. (A) Test samples [Ceramic resonators] We use the following two samples for evaluation: Typical sample: Worst sample: [IC] In case of providing random IC samples from IC manufacturers. IC dependence : Temperature dependence: Power supply dependence: Open loop characteristics: Test all samples at room temperature. Test sample with worst oscillation start voltage. Test sample with worst oscillation start voltage. Test sample with worst oscillation start voltage. sample with average resonant impedance, (TYP.) sample with worst resonant impedance, (WST.) By combining these samples(ceramic resonator and IC), you can find the typical and worst characteristics of the oscillation circuit. (B) CMOS inverter characteristics Measure a CMOS inverter's gain vs. frequency characteristics to check on the gain margin. (C) Oscillation characteristics Fig. 1 shows a basic oscillation circuit composed of a CMOS inverter and ceramic resonator. Each character represents the following. CL1: CL2: Rf: Rd: VDD: (TA: Input Loading Capacitor Output Loading Capacitor Feedback Resistor (Some Ics have built-in feedback resistor) Damping Resistor Power Supply Voltage Ambient Temperature) 1 VDD IC inverter in out A Rf B Rd C V1H/V1L CL1 CERAMIC RESONATOR CL2 V2H/V2L Fig. 1 Basic ...