小尺寸的ECS無源晶體支持時序解決方案ECS-200-20-5PXDN-TR，更高的等效串聯電阻 (ESR) 是工程師在使用更小的無源晶振晶體時會看到的其他東西。ESR是內部電阻，代表電子電路中的能量損失。幾乎每個電路都會有不同程度的某種 ESR。

ESR的水平取決于許多因素，例如特定的結構、材料、質量等。ESR可以在從幾毫歐到幾歐（或 1,000 毫歐）的任何地方測量。如果ESR太高，您可能會看到不同的結果，例如晶振功率損耗、效率低下和電路不穩定。

Higher equivalent series resistance (ESR) is something else engineers will see with smaller crystals. ESR is the internal resistance and represents the loss of energy in an electronic circuit. Almost every electrical circuit will have some kind of ESR to differing degrees.

The level of ESR depends on many factors such as the specific construction, materials, quality, etc. ESR can be measured anywhere from a few milliohms to several ohms (or 1,000 milliohms). If the ESR is too high, you may see varying results like power losses, poor efficiency and instability in circuits.

As a general rule, smaller crystals result in higher ESR, but there are several other factors including frequency, electrode size and mounting structure. With all of these factors involved and the potential effects of ESR, it’s easy to see why it can’t be overlooked when considering using smaller quartz crystals in oscillators. A stable oscillator can’t be guaranteed without it.