Equivalent Series Resistance - ECS Inc. International

Equivalent Series Resistance is the effective resistive component in series with the LC model of the crystal itself. A typic al range is 25Ω to 100Ω for most crystals. While oscillator circuits can tolerate some degree of series resistance, excessive crystal series resistance can lead to oscillator startup failure. So, sufficient margin must be built into the oscillator design.

The exception to the above guidelines are 32.768 kHz watch crystals, where ESR can range from 40~70k Ohms Typical.

ECS Inc. International
15351 W. 109th Street
Lenexa, KS 66219
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