小尺寸的ECS无源晶体支持时序解决方案ECS-200-20-5PXDN-TR，更高的等效串联电阻 (ESR) 是工程师在使用更小的无源晶振晶体时会看到的其他东西。ESR是内部电阻，代表电子电路中的能量损失。几乎每个电路都会有不同程度的某种 ESR。

ESR的水平取决于许多因素，例如特定的结构、材料、质量等。ESR可以在从几毫欧到几欧（或 1,000 毫欧）的任何地方测量。如果ESR太高，您可能会看到不同的结果，例如晶振功率损耗、效率低下和电路不稳定。

Manufacturer Part Number原厂编码	Manufacturer厂家	Series型号	Type 系列	Frequency	Operating Temperature 工作温度
ECS-.327-6-12-TR	ECS晶振	ECX-12	kHz Crystal (Tuning Fork)	32.768kHz	-40°C ~ 85°C
ECS-200-20-5PXDN-TR	ECS晶振	CSM-7X-DN	MHz Crystal	20MHz	-40°C ~ 85°C
ECS-200-20-5PXDN-TR	ECS晶振	CSM-7X-DN	MHz Crystal	20MHz	-40°C ~ 85°C
ECS-200-20-5PXDN-TR	ECS晶振	CSM-7X-DN	MHz Crystal	20MHz	-40°C ~ 85°C
ECS-135.6-20-3X-EN-TR	ECS晶振	CSM-3X	MHz Crystal	13.56MHz	-40°C ~ 85°C
ECS-135.6-20-3X-EN-TR	ECS晶振	CSM-3X	MHz Crystal	13.56MHz	-40°C ~ 85°C
ECS-135.6-20-3X-EN-TR	ECS晶振	CSM-3X	MHz Crystal	13.56MHz	-40°C ~ 85°C
ECS-200-CDX-0914	ECS晶振	CSM-3X	MHz Crystal	20MHz	-60°C ~ 105°C
ECS-200-CDX-0914	ECS晶振	CSM-3X	MHz Crystal	20MHz	-60°C ~ 105°C
ECS-200-CDX-0914	ECS晶振	CSM-3X	MHz Crystal	20MHz	-60°C ~ 105°C
ECS-40.3-20-5PX-TR	ECS晶振	CSM-7X	MHz Crystal	4.032MHz	-10°C ~ 70°C
ECS-40.3-20-5PX-TR	ECS晶振	CSM-7X	MHz Crystal	4.032MHz	-10°C ~ 70°C
ECS-40.3-20-5PX-TR	ECS晶振	CSM-7X	MHz Crystal	4.032MHz	-10°C ~ 70°C

小尺寸的ECS无源晶体支持时序解决方案ECS-200-20-5PXDN-TR，一般来说，较小的晶体会导致较高的ESR，但还有其他几个因素，包括频率、电极尺寸和安装结构。考虑到所有这些因素以及ESR的潜在影响，很容易理解为什么在考虑在振荡器中使用较小的石英晶振时不能忽视它。没有它就无法保证稳定的振荡器。

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.