Keithley I-V Tracer Overview

[Music] [Applause] [Music] hi my name's Brad I'm an applications engineer with Keithley instruments and Tektronix this video will introduce the features of Keith Li's IV tracer an app for our 2,400 series of graphical source measure units that allows you to trace current voltage characteristics of two terminal devices similar to how a traditional curve tracer like a Tektronix 576 or 370 would work IV tracer takes over the front panel display of your source measure unit and allows you to directly control the output voltage or current with the front panel knob while plotting current versus voltage in real time this allows you to quickly verify specifications identify points of failure or even compare two similar devices let's dive right in shall we first I'll demonstrate how to get to IV tracer after it's installed on the latest firmware of your source/measure unit you'll find this apps icon added to the menu you can find a variety of apps for this screen on techcom if you want right now I only have IV tracer installed on clicking the Run button the app starts and takes over the user interface to turn my SMU into a two terminal curve tracer let's hook up a device I've connected that diode at the bottom so we can trace its characteristic curve turning the output on you can see a magenta dot appear that will always be the last measured point turning the knob allows me to change the output level while plotting the IV curve moving slower changes the output in smaller steps like you might expect if I increase the level too high you'll see a yellow limit warning appear as the output level is restricted we'll see how to adjust that limit later if I hold at a single point you can see the exact measured value continue to update in the lower right since the output stays on after all I set my upper voltage bound a little too high for this curve you can tell because of all the extra space on the right I'll use the auto scale function to make my curve fill the entire screen then I'll adjust the increased zoom by pinching slightly - now that I've zoomed my display in the output step size of one knob click has been adjusted accordingly that is as you zoom in the step size decreases I'll zoom in a little mortu this really helps when you want to carefully trace into a device's operating region like looking at the knee of this diode curve the minimum output resolution depends on which 2400 series graphical SMU you're using for a 24 50 like this one the minimum resolution is 500 animals or 500 femto amps when sourcing current hitting the reset button will reset the display but keep your output level and other settings intact next I'll show you how to compare two different device curves first I'll turn the output off and press the compare button to save this curve as a reference it's now stored in the instruments memory I'll change to a different diode now I've already traced its curve as you can see pressing compare again I'll enable the compare mode and I can see my reference show up in blue it overlays on my current trace and matches any zooming that I perform this mode is really helpful for looking at diode behavior on transistors when you might want to compare leakage curves among a batch of devices I want to show you the settings screen and different polarities now as I go to the menu button you can see the menu screen is completely different from normal this settings screen holds most all the settings you'll care about there's a shortcut to get here from the main screen you can see their settings for outputting either voltage or current the peak output level measurement limits effectively the power limit selecting to wire or four wire sense and the polarity setting what I'm going to do now is change the polarity from positive DC to negative DC this means I'll be sourcing a negative voltage instead of a positive one I'll also change my peak output level from two volts to ten volts this is because I want to see the Zener voltage of this diode I have connected which should be around negative nine volts I'll trace up or down to it now notice I still move the knob clockwise think of the knob as controlling a percentage of your output level instead of changing the output level directly I should really zoom in on this knee here but I want to show you other polarity still now I've kept the same Zener diode but I've swapped my instrument to a 2461 SMU this SMU has dual 1 mega sample per second digitizers that allow for much faster measurements including enhanced pulse behavior and an AC mode I'll take the settings shortcut and you can see the option to enable pulsing here this mode is very helpful to prevent self-heating effects from changing your curve enabling it allows you to adjust the pulse width what I'll show you now though is the AC polarity this polarity outputs a sine wave about zero volts the level you set with the knob now becomes the amplitude of this wave the frequency matches your line frequency when sourcing current the instrument source is a cosine wave instead that'll take a separate video to go into though anyway I'll change my peak level back to ten volts so my AC wave now has a maximum amplitude of 10 volts from zero going home I'll turn the output on and ramped up the amplitude you can see my wave is now centered at zero on the positive end my device is protected from a dangerous amount of power with my current limit setting on the negative end I can continue ramping until I see the full behavior of this Zener diode IV tracer comes with a dedicated kickstart app that you can use to transfer data to your computer simply click the collect button in the bottom left to bring over the curve from your SMU kickstart offers you a table view for looking directly at measurements and a graph view for a more visual analysis you can of course export the data from here to another program if you wish this kickstart app is also how you install IV tracer look for our other video on that topic IV tracer can be used anywhere your SMU can using either the front or rear terminals which makes it a very portable solution remember that if you want to use voltages above 40 volts you'll need to use a test fixture that can satisfy interlock this is to prevent accidentally touching any hazardous voltages that's particularly relevant for the 2470 which has a thousand volt range very helpful for tracing into reverse breakdown voltages for most cases though I find a simple breadboard like this one or even some clip-on leads are sufficient I hope this video has been helpful you can install a trial of IV tracer to your own instrument by connecting it to kickstart keith lee's benchtop instrument control software or you can learn more by visiting techcom slash Keithley IV tracer thanks for watching find out more at four coms website you

Channel: Vicom New Zealand

Views: 1,420

Rating: 5 out of 5

Keywords: Curve Tracer, SMU, Sourcemeter

Id: ArXA4XRR82A

Length: 6min 58sec (418 seconds)

Published: Wed Feb 26 2020