Picoscope Using Xy Mode. Where Voltage and Current Would Be Plotted Against Each Other

Insertion

From the classic Lissajous pattern to state transition diagrams for nonclassical quadrature communications systems X-Y plots provide a view of functioning relationships between to waveforms. X-Y plots potty be displayed alone OR in colligation with the X-T and Y-T components. Combined with X-Y cursors it is thinkable to make measurements using some Cartesian and polar coordinates. In this application brief we volition consider or s normally used X-Y measurements.

Lissajous Patterns

For most engineers institution to X-Y displays is via the standard Lissajous approach pattern where two sin waves are plotted, unity against the other. This display can depict the relative phase of the sine waves. In the pillowcase where the sin waves are at different frequencies, we can determine the ratio of the two frequencies as shown in Figure 1 where a 10 and 25 MHz sine waves are used A inputs to the Lissajous pattern. Note that X-Y displays are set up victimisation the Display dialog box Eastern Samoa shown in Human body 1.

Figure 1:

A Lissajous pattern with 10 Mhz and a 25 Megacycle per second sinewavess planned against each other

The user can select which waveform is abutting to the vertical axis and which is associated with the horizontal axis. The number of vertical peaks (5 in this case) and flat peaks (2) signal the frequency ratio of the vertical (Y) Axis to crosswise (X) axis. In this shell 5/2 (25/10 MHz).

AM Mensuration

A slightly more sophisticated version of the Lissajous pattern is the trapezoidal diagram of Calculate 2.

Figure 2:

A trapezoidal plot for measuring the intonation index of an amplitude modulated waveform

Therein X-Y secret plan the Y axis vertebra is the amplitude modulated flattop (C2) . The X axis is the modulation signal (C1). The intonation index number of the amplitude inflected signal can be determined by measuring the lengths of the vertical sides of the trapezoid. If the distance of the leftist hand side is called Q and that of the right handwriting segment called P then the modulation indicant, m, can be computed A;

$$m = {(P-Q)/(P+Q)}$$

In our illustration P=4 and Q=1 division respectively. The value of m is 0.6 which represents 60 % modulation.

Moving into the domain of power measurements we can plot the current done a great power field effect transistor (FEt) as a function of the drainage to source voltage in a switched way power supply. The resulting plot is titled a safe operating region (SOA) secret plan. An example is shown in Figure 3. In this screen visualize channel 1 is the current wave shape and channel 2 is the potential waveform. When the FET is along the drain-source voltage is close

Figure 3:

The safe operating area (SOA) diagram for a switching musical mode exponent furnish

to zero and the current ramps skyward from zero to a uttermost value. This forms the vertical section on the left of the SOA plot. When the current is zero the voltage waveform plots as the swimming section on the bottom of the SOA plot. When the FET is changing state we get simultaneous cardinal current and voltage values which show as the curved sections joining the linear elements antecedently discussed. These are regions of finite exponent dissipation. Higher power levels are indicated by moving upward and to the right on the SOA plot.

Other common king mensuration is the hysteresis OR B/H curve for an electromagnetic component like an inductance of transformer. Magnetic materials are characterized by plotting magnetic induction (B) as a function of magnetic field strength (H).

Figure 4 shows how an inductor is related to generate a B/H curve.

Cypher 4:

Setup for measuring a B/H curve ball

In Cypher 5 we have a screen image of such a B/H curve.

Figure 5:

The range setup for creating a B/H curve

Note that the emf wave shape has to be integrated systematic to influence the magnetic fuse tightness. In Figure 5 we give birth a screen image of such a B/H swerve.

Trace M3 contains the current waveform which is applied to the X input. The potential dro waveform is integrated exploitation the Math function and applied to the Y input signal.

The area within the hysteresis loop is relative to the energy loss per motorbike. This region butt also be measured as described in LeCroy Practical application abbreviated LAB_707A.

Our final example of X-Y plots comes from the world of communications. Modern communications systems employ a variety of quadrature inflection schemes. These are form modulation systems that use baseband in phase (I) and quadrature (Q) components to modulate a postman. Cross plots of the I and Q components, known as state transition diagrams, supply information on the bounty and form of the resultant vectors. In accession to showing the vector components ane can measure the magnitude and phase suing X-Y cursors.

Soma 6 is an example of a state transition plot for a PHP cellular telephone system. The I waveform is applied to the horizontal or X bloc and the quadrature (Q) portion is applied to the vertical operating theatre Y input. This type of X-Y patch also employs display persistence to hold up a history of multiple information values on the screen.

Material body 6:

State Transition Diagram for a PHP cellular phone system utilizes display persistence and X-Y display

Summary

Thither are many applications which do good from X-Y displays. These are a a couple of of the more commonly used applications. LeCroy oscilloscopes incorporate X-Y displays along with persistence and specialized cursors to get the just about respect from this useful tool.

Picoscope Using Xy Mode. Where Voltage and Current Would Be Plotted Against Each Other

Source: https://teledynelecroy.com/doc/using-xy-displays