Oscilloscope Probe X1 X10 Difference | Detection and Compensation of Probes

Passive voltage scope probes are classified into two types. They are usually labeled X1 and X10, while 1X and 10X are occasionally observed. The term relates to the factor by which the probe multiplies the impedance of the scope itself. 

An X1 probe does not diminish or attenuate the input signal, whereas an X10 probe reduces the signal’s amplitude at the scope input to 1/10th of the signal’s amplitude. 

What Are the Basic Differences Between X1 and X10 Probes

The basic differences between X1 and X10 probes are listed below:

	X1	X10
Attenuation	A 1x probe links the scope to the test point directly, with no further attenuation.	The “standard” probes that come with most scopes are ten – X probes. They lower the amplitude of the signal by a factor of ten.
Sensitivity	1x probes are more sensitive and can detect little signals more easily (±30 V).	Less sensitive than X1 probes due to the attenuation caused by X10 probes.  It can measure up to ±300 V.
Maximum Amplitude	When the signal level is low, less than 40V peak to peak, a 1x probe is useful.	Because of the additional attenuation, 10x probes are suitable for high-voltage measurements (400Vpp).
Bandwidth	The scope’s input capacitance works as a low pass filter, 1x probes have a limited bandwidth (6MHz).	10x probes have a significantly larger bandwidth than 1x probes (10MHz).
Loading effect	High	Less
Impedance	1 MΩ // 100pF	10 MΩ // 20pF

How Does Oscilloscope Detect Probes

In some circumstances, a scope can determine whether a probe is 1x or 10x and automatically modify its settings. This is feasible because many 10x probes contain a metal pin on the scope side, and if this hits a sensor ring on the scope input, the scope detects the usage of a 10x probe.

Figure 1: X10 probes with a metal tip

Also, the internal circuit of X10 probes is different than that of X1 probes.

Figure-2: X10 probe circuit(left one) and X1 probe circuit (right one)

Frequently Asked Questions and Answers (FAQs)

Can I Switch Between X1 and X10 on the Same Probe

By adjusting a switch on the side, some probes can be used as 1x or 10x probes. Switchable probes are what they’re called. If the probe attenuation isn’t detected automatically when using a switchable probe, make sure you update the scope settings properly.

Do X1 and X10 Probes Have Different Input Resistances?

Yes, the input resistance to both probes is different. An X10 probe has an input resistance equal to 10MΩ, as it has to attenuate the input signal to 1/10^th of its original input. Whereas, X1 probes have an input resistance of 1 MΩ as no attenuations are required in this case.

What Is Probe Compensation in X10 Probes

Probe compensation is used to match the capacitance in the probe tip to the capacitance in the oscilloscope’s inherent input capacitance. Before using passive probes, it’s a good idea to adjust them to reduce amplitude and pulse shape inaccuracies in the measured signal.

Conclusion

Oscilloscope probes are a must-have accessory for any oscilloscope. Most of the time, 10X passive scope probes are utilized, although various types of test probes must be considered depending on the applications.