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Advanced Operation

*Figure 5-45 GRAPH MODE – Set *

Figure 5-45 shows **GRAPH MODE** set up to plot a graph of inductance against frequency on a linear scale between 100kHz and 600kHz with the limits set in absolute terms.

**5.15.1 GRAPH MODE – Set Parameters **

Parameters which are common to **IMPEDANCE MODE** are described in section 4.7.2—

IMPEDANCE MODE Parameters.

**Lin(***unit***) Log(***unit***) **

**Lin(Z) Log(Z) **

**Sweep **

Toggles between **Lin(***unit***)** and **Log(***unit***) **to set either linear or logarithmic horizontal scale, where *unit* is the unit of the **Sweep** parameter (see **Sweep**, below).

This soft key is displayed only when **Log(***unit***)** is selected (above) and when **Mode** is set to **Impedance (Z+θ)**. It allows selection of

Lin or Log vertical scale, allowing log/log graphs to be plotted.

Note that negative or zero scale limits cannot be plotted on a log scale. Both limits must be set to positive values before pressing

**Start**, or a warning message will be displayed.

The **Start** and **Stop **settings for the graph, which are set by highlighting each in turn with the and navigation keys, then entering the value with the data entry keypad. When **Sweep **is highlighted the and navigation keys are used to set the

**Sweep** parameter to **Frequency**, **Bias**, **Bias (Boost)** or **Drive **

**Level**.

**Step Size **

**Mode **

**Abs % **

**Major/Minor **

**Term Select **

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The **Step Size **is the number of LCD display pixels used for a single point along the graph. The higher the number selected, the coarser the graph but the more quickly it is plotted. Set by highlighting **Step Size** with the and navigation keys, then select from **1 2 4 8** with the and navigation keys.

When the **Mode** parameter is highlighted with the and navigation keys, it may be toggled between **Impedance… **mode or

**Transformer…** mode parameters (see **Major/Minor Term **

**Select**, below) with the and navigation keys. Once this selection is made, the expected **Hi** and **Lo** limits for the y axis of the graph may be highlighted with the and navigation keys and the values entered with the data entry keypad. If percentage limits are selected, a **Nominal **value must also be entered: no units are necessary, this will always match the major term selection.

This soft key toggles between **Abs** and **%** (major term only).

When **Abs** is selected, absolute **Hi** and **Lo** limits (i.e. units of the measured parameter) are displayed. When **%** is selected, a

**Nominal** value together with **Hi** and **Lo** percentage limits is displayed.

The limits and nominal value (if applicable) must be set using the

and navigation keys to highlight each parameter and the data entry keypad to set each value.

**Note:** The **Abs %** soft key is not available when the vertical scale is logarithmic.

This soft key toggles between either of the measurement terms selected in **IMPEDANCE MODE** or **TRANSFORMER MODE** depending on whether the **Mode** parameter is set to **Impedance…** or **Transformer…**. The graph will be plotted according to whichever of these terms is highlighted.

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**Start **

**View **

**IMPEDANCE **

or

**TRANSFORMER **

Advanced Operation

When all parameters have been set up, pressing the **Start** soft key will plot the graph.

As the graph is being plotted, a progress marker at the bottom of the screen shows how complete the graph is and the speed of the marker gives an indication of how long the graph will take to plot.

If the graph is progressing too slowly, perhaps because too small a

**Step Size** has been selected, it can be aborted by pressing and

*holding* the **Abort** key.

**Notes: **

1) If the range is manually selected and the component characteristics take the graph outside the boundaries of the selected range, that portion of the graph will not be plotted.

2) If incorrect y axis settings are selected, no graph will be seen even though the progress marker will indicate that a graph is being plotted: the graph will actually be ‘plotted’ outside of the display area. The display can be corrected by using the

**FIT** autoscale function, or by pressing the **RETURN** soft key and selecting more appropriate limits.

3) An error message shown at the top of the screen indicates that the error occurred somewhere on the sweep.

4) The graph is plotted using the full measurement resolution.

When the graph has been plotted and **GRAPH MODE – Set **has been reselected with the **RETURN** soft key, **View** can be used to redisplay the last graph plotted by the analyzer.

Enters **IMPEDANCE MODE** or **TRANSFORMER MODE** according to the **Mode** selected (see **Mode**, above) so that measurement parameters may be set up or changed. When the correct measurement parameters are set, the **RETURN** soft key returns the instrument to **GRAPH MODE – Set**.

**5.15.2 Parameters Available when the Graph is Displayed **

**FUNCTION **

**VIEW **

**FIT **

Pressing **FUNCTION **temporarily crops the graph to display other soft keys available. These are shown indented below:

Pressing **VIEW **hides the available soft keys and displays the whole graph.

The **FIT** soft key replots the graph, auto scaling the vertical axis for the best available resolution. This may be done separately for both major and minor terms.

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**TOGGLE **

When a graph is plotted on the major or minor term, the other term is automatically stored in the background and the **TOGGLE **soft key can be used to toggle between the two graphical displays.

**RESONANCE **

Enters **RESONANCE MODE**. See section 5.16.

**PEAK **

Aligns the marker with the highest peak in the set frequency range.

**DIP **

Aligns the marker with the lowest trough in the set frequency range.

**NOM>MK **

**PRINT **

**RETURN **

Replots the graph with the marker position set as the component nominal value. To aid positioning of the marker, its position in both axes is shown at the bottom of the screen. It is moved with the and navigation keys. When **GRAPH MODE – Set** is reentered with the **RETURN** soft key, the **Nominal** and **Hi**/**Lo** limits will reflect the replotted graph.

Prints the graph on an Epson-compatible printer after entering

**Code 30** from the **MAIN MENU**.

Returns the analyzer to **GRAPH MODE – Set**.

**Note **

If the DUT exhibits high Q resonances, the graph function may miss the peak or trough due to quantized frequency steps. For accurate values at resonance, use the **RESONANCE** function.

**5.15.3 Example **

This example will illustrate the procedure for using **GRAPH MODE** and is intended to familiarize the user with this mode of operation. For this example a linear scale will be used to plot inductance over the frequency range of 100kHz to 600kHz.

1) Enter **GRAPH MODE – Set** by pressing the **GRAPH** soft key from the **MAIN MENU**.

2) Highlight the **Sweep** parameter with the or navigation key, then using the and navigation keys set it to **Frequency**.

3) Highlight the **Start** frequency with the or navigation key and enter the required frequency with the data entry keypad. For this example **100kHz** will be entered.

4) Highlight the **Stop** frequency with the or navigation key and enter the required frequency with the data entry keypad. For this example **600kHz** will be entered.

5) Highlight **Step Size** with the or navigation key, then use the and navigation keys to select **1 2 4** or **8**. For this example **2** is selected.

6) Highlight the **Mode** parameter with the or navigation key, then using the and navigation keys set it to **Impedance…**.

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Advanced Operation

7) Press the **IMPEDANCE** soft key. This will display **IMPEDANCE MODE** where the appropriate parameters must be set prior to plotting the graph. Enter the parameters required for the test. For this example they are set to:

**AC Meas **

**L **

**R **

**1.00Vac **

**1.0000kHz**—this setting will be overridden when the graph is plotted

**DC Bias 0.000 A OFF NORM**

**Range Auto **

**Speed Med **

**ALC off **

When the measurement parameters have been set, press the **RETURN** soft key to return the instrument to **GRAPH MODE– Set**.** **

8) Highlight the **L** and **R** **Hi** and **Lo** limits with the or navigation key, then set each in turn with the data entry keypad. For this example they will be set to:

**L Hi: 100.00m **

** Lo: -100.00m **

** Lo 1.000Ω **

9) Use the **Lin(Hz) Log(Hz)** soft key to highlight **Lin(Hz)**.

10) Use the **Abs %** soft key to highlight **Abs**.

The screen should now look like Figure 5-45.

11) If necessary, press the **CALIBRATE** soft key and perform the appropriate trims for the

**Mode** selected. See section 4.3 for details of the trim procedure.

12) Connect the component to the test leads or fixture.

13) Press the **Start** soft key. A graph will be plotted showing the component characteristics using the measurement parameters and frequency range set (Figure 5-46).