dc load line in ADS.

[vahidnoori]

hi.
i going to design power amplifier by ADS .but in DC simulation i cant plot load line inn I-V curve. can help me?

 

[BigBoss]

In ADS Component Palette, there is a IV Curve Tracer element to obtain for BJT and FET transistors.Use that..

 

[vahidnoori]

In ADS Component Palette, there is a IV Curve Tracer element to obtain for BJT and FET transistors.Use that..

thanks for your guide .and how can i select best point in IV curve for (for example) AB class power amp?

 

[BigBoss]

thanks for your guide .and how can i select best point in IV curve for (for example) AB class power amp?

"The Best Point" is quite variable for the active device which you intend to use.Therefore, you should select a appropriate point and then try to optimize this OP in according to you specifications.
I recommend Load Pull technique to find a compromised OP.

 

[vahidnoori]

In ADS Component Palette, there is a IV Curve Tracer element to obtain for BJT and FET transistors.Use that..

where can i find IV curve tracer?

 

[RealAEL]

You have 2 options to do this. Either:

Create a new schematic design, using File > New Design... from any open schematic window, and in the New Design window under the "Schematic Design Template (Optional)" select the drop down list and pick either BJT_curver_tracer or FET_curver_tracer as required. Add you device to the schematic and connect as appropriate.

Or

Open the "Simulation - Instrument" palette and add either the "DC BJT" or "DC FET" curve tracer symbol to an existing schematic design. Then connect the Base/Collector or Gate/Drain pins to the device to be tested.

 

[vahidnoori]

You have 2 options to do this. Either:

Create a new schematic design, using File > New Design... from any open schematic window, and in the New Design window under the "Schematic Design Template (Optional)" select the drop down list and pick either BJT_curver_tracer or FET_curver_tracer as required. Add you device to the schematic and connect as appropriate.

Or

Open the "Simulation - Instrument" palette and add either the "DC BJT" or "DC FET" curve tracer symbol to an existing schematic design. Then connect the Base/Collector or Gate/Drain pins to the device to be tested.

:
this module (DC_FET) can plot just IV curve i am seeking the manner that plot load line on IV curve like this image :
https://obrazki.elektroda.pl/8217285300_1390335972.jpg

and which can i select best point for AB amp?

 

[RealAEL]

Those 2 load lines appear to be simply equations that we manually added to the graph display for the IV curves. Something like this:

 

[vahidnoori]

Those 2 load lines appear to be simply equations that we manually added to the graph display for the IV curves. Something like this:

View attachment 101372

thanks for your guide. but a question : what is the constant parameter (for example .015 , 226.667 in line equation ) ? for my FET model how can i determine them? I'm sorry for the stupid question

 

[RealAEL]

These are just numbers that happen to work for the example case. The 0.015 is the point where the line crosses the Y axis and represents the maximum current through the transistor. The 226/333 numbers are the slope of the load line and would represents some sort of (load) resistance. There is no way to get ADS to automatically generated these lines I just demonstrated a method of entering them manually.

 

[vahidnoori]

how can i determine maximum current?

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or how can i determine load resistance?

 

[vahidnoori]

These are just numbers that happen to work for the example case. The 0.015 is the point where the line crosses the Y axis and represents the maximum current through the transistor. The 226/333 numbers are the slope of the load line and would represents some sort of (load) resistance. There is no way to get ADS to automatically generated these lines I just demonstrated a method of entering them manually.

How can I determine maximum current or load resistance?