How is the capacitance of the oscilloscope probe equal to?
By adjusting it, the total capacitance of the oscilloscope input capacitor and the compensating capacitor can be made equal to 9 times the probe capacitance. Thus these capacitors would form a 10:1 voltage divider.
Do you need frequency compensation for oscilloscope probes?
Frequency compensation for oscilloscope probes is required when using a voltage type probe that includes an attenuator, i.e. X10, X100 or other values. Scope probe compensation is not required for X1 probes.
How to tune the HFC of an oscilloscope probe?
One controls the mid-band frequencies and the other the high-band. Both should be adjusted until the correct response is obtained. To tune the HFC of a probe, a square wave with a very fast edge must be input into it. The waveform must have a fast edge (3x shorter rise time than the probe) with very little or no overshoot.
Where is the compensation adjuster on an oscilloscope?
On some scope probes the compensation adjuster is at the tip and others it is in a small box by the connector that mates with the oscilloscope. It is also surprising to note the frequencies at which compensation starts to be required. With a 9MΩ resistor in the tip, the 25pF or so capacitance starts to be noticed at a very low frequency.
What are the effects of capacitive loading on an oscilloscope?
Another effect is the reduction of system bandwidth due to the capacitive loading of the oscilloscope. This also affects the dynamic timing measurements such as pulse risetime. Oscilloscope designers have sought to minimize these effects by approaching the loading problem from two different points of view.
What is the impedance of a 300 MHz oscilloscope?
The impedance input of a typical 300 MHz bandwidth oscilloscope consists of a 1 MOhm resistance in parallel with a 15 pF capacitor. Direct connection of the oscilloscope to a circuit by means of a coaxial cable or X1 probe will add an additional capacitive load, due to the cable, of approximately 50 pF per meter.
What is the theoretical accuracy of an oscilloscope?
As you can see in Equation 1, the oscilloscope’s voltage measurement accuracy is the most critical factor in the total test accuracy. Based on Equation 1, the theoretical accuracy of this measurement method should be about 4% at the MDO4000’s 1 mV/Div setting and 3% at other settings.