Advertisement

Blog

GaN & SiC Testing Needs Give Rise to a 2,500 V Power Op Amp

The hybrid IC is not extinct. Hybrids can be tuned to give superior specifications, especially in drift over temperature and noise that cannot be reached with a high volume monolithic device.

Apex Microtechnology took its hybrid Op Amp performance to more than double the output voltage of any previous designs. The PA-99 is targeted for power supplies and test equipment suppliers especially in the GaN and SiC Power device arena.

The age old, tried and true cascaded topology, in the output drive circuitry that has served many an operational amplifier design, is still a reliable architecture that operates at 2,500V supply with more than 2,400V output capability. The IC is able to operate with symmetric or asymmetric power supplies with the only condition being the voltage between the positive and negative supply rails not exceed the maximum supply voltage spec.

As for the output current, the PA99 provides a minimum of 20 mA continuously and as high as 50 mA peak. (Of course any power amplifier must be operated within its Safe Operating Area.) External resistors set the output current limit in order to prevent excess current from damaging the amplifier or the load. The output can source or sink current as well and drive any type of resistive, capacitive, or inductive loads.

The addition of a temperature monitoring diode adds an order of protection to the die in the hybrid as well, which improves the lifetime of the ICs on board. Slew rates of 25 to 35V/us are achievable at this high voltage as well.

Designers were aware that customers want as small a footprint as possible, especially when multiple devices are used in test equipment. A hermetic Power-DIP package filled with inert gas helps reduce the required package height and makes for better spacing of the internal components. A 12-pin Power-DIP package was able to be used for a small footprint.

For more detail visit the Apex Microtechnology website.

33 comments on “GaN & SiC Testing Needs Give Rise to a 2,500 V Power Op Amp

  1. samicksha
    November 27, 2014

    No doubt in that GaN/ SiC are better on high temperature performance, The tester must be able to withstand high SiC and GaN voltages and fast switching speeds.

  2. Netcrawl
    November 27, 2014

    @samicksha you're right, GaN on SiC is also well suited for high performance RF applications, gaN on SiC offers superior thermal properties compared to GaN on Si and therefore ideally suited for applications with high power density requirements. Vendors of GaN on SiC-based devices have demonstrated considerable success in their early efforts-especially in the electronic warfare space.

  3. Netcrawl
    November 27, 2014

    @samicksha diamond is also an excellent electrical insulator, a property needed for high frequency power amplifiers. In addition, the spatially shrunken GaN-on-diamond devices can operate amidst a much higher ambient temperature compared to GaN-on-SiC. This is due to the thermal impedance stack between the GaN channel and the substrate, GaN-on Diamond also holds promise for use in cellular base stations where operating energy costs in cooling the PAs can be significantly for service providers.

    GaN-on Diamond's ability to operate in a much higher temperature than any other semiconductor material translates into direct cost savings, smaller power supplies and less energy use.

  4. chirshadblog
    November 27, 2014

    @samicksha: Yes if not the entire performance will drain plus will make the app misbehave

  5. dassa.an
    November 28, 2014

    @Netcrawl: Yes it's a good sign indeed and that shows there is hope and people are willing to take the risk. I guess these are mostly co-operate clients 

  6. dassa.an
    November 28, 2014

    If there are some back-up alternatives or a mirrored version in case for an emergency, it will not be a problem

  7. samicksha
    November 28, 2014

    GaN-on Diamond's ability to operate in a much higher temperature than any other semiconductor material translates into direct cost savings, smaller power supplies and less energy use.


    I agree you Netcrawl, GaN on Diamond can help us in reducing thermal resistance, increasing RF power density, but this shall add lot more cost than we are spending today.

  8. yalanand
    November 28, 2014

    A hermetic Power-DIP package filled with inert gas helps reduce the required package height and makes for better spacing of the internal components.

    @Steve, thanks for the post. I never knew inert gas is used inside DIP package. I am curious to know if this procedure is being used by all the companies or is it pioneered by Apex Microtechnology. 

  9. Steve Taranovich
    November 28, 2014

    @yalanand—I have asked Apex to comment on this, but from what I see, this can only be done in a hermetic package and with a high voltage design–there are not many of these around that I know of.

    Of course, the inert gases have been used in arc suppressors, etc in high voltage electrical transmission and equipment for many years, but as for in an IC package—Apex might be one of the rare few IC companies to do it, but I will leave it to them to comment on being the first semiconductor supplier to do it

  10. yalanand
    November 29, 2014

    I have asked Apex to comment on this, but from what I see, this can only be done in a hermetic package and with a high voltage design–there are not many of these around that I know of.

    @Steve, thanks for the reply. I agree with you that not many of them use this technology. Lets see what Apex comments about this.

  11. chirshadblog
    November 29, 2014

    @yaland: What is the primary cause for it to be not used on a regular basis ? 

  12. chirshadblog
    November 29, 2014

    @yaland: Well though it was kind of new many are using it already. 

  13. yalanand
    November 29, 2014

    @yaland: Well though it was kind of new many are using it already.

    @chirshadblog, thanks for correcting me. Can you please give more details about who are using such technology already ?

  14. yalanand
    November 29, 2014

    What is the primary cause for it to be not used on a regular basis ?

    @chirshadblog, I assumed it would be tedious process to fill inert gas inside the DIP package. Moreover I have never came across this step when studying about process steps.

  15. dassa.an
    November 29, 2014

    @yalanand: Well this is kind of news to me. I guess its here to stay

  16. dassa.an
    November 29, 2014

    @yalanand: Is it that new ?

    @Chris: What sort of industries are using it ? I have seen some articles but did not have time to read them properly

  17. dassa.an
    November 29, 2014

    @yalanand: What is the difference of it compared the earlier version ? Is it the price or performance ? 

  18. yalanand
    November 29, 2014

    What is the difference of it compared the earlier version ? Is it the price or performance ?

    @dassa.an, I am sorry I dont have much information about the cost comparison. I think Apex Microtechnology would be in a better position to comment on that.

  19. Steve Taranovich
    November 29, 2014

    @yalanand—One big difference is the supply and output voltage capability of the PA99 which is 2X the nearest competitor—it's own PA89 op amp at 1,200V

  20. samicksha
    November 29, 2014

    I am curious to find what will be the testing parameters, wherein i found about Keithley Instruments has introduced the Parametric Curve Trace configurations , specifically designed for high voltage and current characterization of high power semiconductors. But i am still struggling to find what and how it will work.

  21. PCR
    November 29, 2014

    Yes dassa.an it is always better to have a backup system in order to face unexpected situations. 

  22. Katie O'Kew
    November 29, 2014

    OP AMPS have come a long way since WW-2 years and the analog computer. Since the very first days of the ISSCC in the mid 1950's and such milestone ICs as the uA741, we witnessed one improvement after another in this basic circuit topology.  Few of these advances were concerned with providing a very large output voltage swing, mostly because the market need for such was quite limited; numerous other performance criteria have been more important.

    The APEX PA99 is a certainly a milestone in its ability to provide an output swing in excess of 2kV, and obviously, this is as much as anything else a tribute to the success in managing the design of the output stages, after finding suitable devices for this purpose. Once that was done, it was probably not hard to complete the design to provide adequate DC and AC gain, an exceptionally high overall slew-rate, and a low-noise, well-balanced front-end.

    Provided this part is sold at a reasonable price – and, I would suggest, supported by APEX with some suitable power-supply blocks – it will find a lot of uses in test systems. It will also deserve mention in any modern survey of the history of the ubiquitous operational amplifier.

    Now, are we ready for 10-kV swings?

    Barrie G. Analog Devices Inc.

  23. Steve Taranovich
    November 29, 2014

    @Katie OQ—10kV will certainly have its own set of  unique challenges, but I am sure the day will come when we see such a “beast”—-SiC has already been tested at 10 kV levels

  24. SunitaT
    November 30, 2014

    i found about Keithley Instruments has introduced the Parametric Curve Trace configurations , specifically designed for high voltage and current characterization of high power semiconductors.

    @samicksha, Thanks for sharing this info. Can you please share where can we find more about Keithley instruments and are there any other similar instruments available ?

  25. SunitaT
    November 30, 2014

    SiC has already been tested at 10 kV levels

    @steve, hanks for this info. What issues do we see at such high voltage and how did they take care of such issues in  SiC testing ?

  26. samicksha
    November 30, 2014

    I believe internet is home of all the information, i am sure you will find it, Google should help here.

  27. Steve Taranovich
    November 30, 2014

    @SunitaT0—Test equipment for SiC needs to have the capability of dynamic testing capable of switching kilowatts in microseconds. The Automatic Test Equipment (ATE) must have advanced driver circuits and very well designed interconnect and layout of tester electronics as well as device-under-test (DUT) sockets and contactors.  Safe and reliable testing necessitates a precise design in the PC cards and surrounding components and chassis for creepage and clearances.  Also, very fast, high power transition times generates ground noise and EMI which must be dealt with.

     

    Some ATE examples are Agilent Technologies Inc. B1505A Power Device Analyzer/Curve Tracer

  28. babjipemmadi
    December 1, 2014

    I must say that overall I am really impressed with this blog.It is easy to see that you are impassioned about you writing.Nice post.i was searching for this post from last 30 minutes on google. and i reach to your website,superbly written and well explained.thanks for your article.looking for other posts also.keep it up.

  29. babjipemmadi
    December 1, 2014

    I must say that overall I am really impressed with this blog.It is easy to see that you are impassioned about you writing.Nice post.i was searching for this post from last 30 minutes on google. and i reach to your website,superbly written and well explained.thanks for your article.looking for other posts also.keep it up.

  30. marierivera
    December 1, 2014

    Good question, Steve, nitrogen is the gas used inside these hybrid packages to maintain low moisture content. The moisture is monitored and must be less than 7000ppm. It typically is less than 2800ppm. And I don't believe Apex Microtechnology can claim to be the first hybrid component manufacture to use this technique.

  31. Steve Taranovich
    December 1, 2014

    @babjipemmadi—Thank you for your kind words—I am very happy to see that you enjoy these tech blogs—I am happy to have you as part of my audience

  32. Steve Taranovich
    December 1, 2014

    @marierivera—that”s awesome—just as I was hoping. Great technology expertise at Apex Microtechnology!

  33. prakash1997
    December 30, 2014

    Thank you for this article.  I'm not as familiar with, so this is a help. 

    Nice post.i was searching for this post from last 30 minutes on google. and i reach to your website,superbly written and well explained.

Leave a Reply

This site uses Akismet to reduce spam. Learn how your comment data is processed.