Is Altera Cyclone a good choice ?

Feb 18, 2005 15 Replies

Dear everybody,



the goal of my post is to collect your opinions about the use of Altera Cyclone devices in a rugged environment. I have to design a board which should control a chopper based on GTOs. The environment is a railway vehicle and the following are the conditions I have to consider:


- extreme temperature range (-40°C to +85°C)



- strong mechanical vibrations



- long life duration (> 25 years)



- high degree of reliability



- very low frequency of maintenance



From the point of view of the design I think Altera Cyclone is the best choise for this kind of project beacuse its high flexibility. But I have some doubts about its functionality in a rugged environment like above.



Did you experience the use of Altera Cyclone in a rugged environment ? What are your opinions about my choise ?



Best Regards



/Alessandro Strazzero


I think the Cyclone would be an excellent candidate. I know its being used in the Oil&Gas industry in down hole tools. This is a far more extreme environment than you're describing.

Of course there is no 25 year history.

Ken

Alessandro ,

We're using it in the gate drive of a high performance IGBT drive. The mechanical/thermal environment isn't too bad, but the EMC environment is pretty tough. We have had no problems.

Gary

Alessandro,

I would request their qualification documents (both process qual, and product qual), and arrange to go over them with their Reliability VP or director. Only then can you make an informed decision.

Asking that question here is not going to reveal this information to you, only a full reading of the qual reports will supply you with that knowledge.

Look for the results of HTOL (high temperature operating life), and how they calculate lifetime and wear-out. Also, number of cycles of self-heating and cooling is vitally important, because externally making the device hot and cold is not asa stressfull as the device itself making itself hot (and cold).

By the way, we would be happy to supply you with that information, and discuss it with you for Sprtan 2E, or Spartan 3 (or any other Xilinx product).

Aust> Dear everybody,

I have heared roumors that the PLL in Cyclone doesn't work below -20C if the output frequency is higher than the input. There is some fine print in the datasheet to that effect.

Now I have no way of knowing if that is true or not - I live in California :))

Cyclone

control

following

choise

doubts

The other question you need to ask is "can I still get them in 25 years time" They usually require some kind of servicing :-)

Simon

Cyclone

control

following

choise

doubts

I dubt his fridge will go as low as -20 °C.

Petter

A: Because it messes up the order in which people normally read text. Q: Why is top-posting such a bad thing? A: Top-posting. Q: What is the most annoying thing on usenet and in e-mail?

So you have a fridge. Put Cyclone into it during PLL work for 30minutes :) And tell us about this experiment - we are interested in it too :) ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

My fridge can go down to -32°C.

Impressive, my freezer wont even go that low. My fridge goes down to

+2 °C. If I want -32 °C I will have to put it outside - on an extreme cold winter night...

Petter

A: Because it messes up the order in which people normally read text. Q: Why is top-posting such a bad thing? A: Top-posting. Q: What is the most annoying thing on usenet and in e-mail?

hmm, :) and where do you store meat? i do it in refrigerating chamber of my fridge. ;)

The PLL in the Cyclone device works down to -40 C. However the lock pin will not correctly show the PLL-locked status if junction temp is below

-20 C AND fIN/N is 200 MHz or less. This detail is shown in the Cyclone datasheet and is what Alex Freed is referring to. N is the divider between the PLL input and the phase frequency detector.

You can get a lock signal one of two ways:

  1. Depending on your fIN/fOUT multiplier, set up the PLL so that fIN/N is more than 200 MHz.
  2. Construct a circuit from LEs that generates a lock signal. One way of doing this is to have a counter driven by the non-PLL clock, and another one driven by the PLL output. (Assuming frequency is the same.) As long as the offset between the two is not changing then the PLL is locked. There's many possible variations of course.

Greg Steinke Altera Corporation

Alessandro, there is nothing exotic about your requirements, and any FPGA from a reputable manufacturer should meet it. Plastic packages are very good in high-vibration environments,

25 years is a long time, but most people design for >10 years at elevated temperature ( a description of how many years at what temperature might help. Parts age at high temperature faster than at cold. High reliability is assumed today for all parts, but you might have to pay extra for any assurance. Low maintenance is the same as high reliability, i.e. long mean-time-between-failure. I do not know why you assume that Altera Cyclone fits this better than Altera Stratix or Xilinx Spartan or Xilinx Virtex. They are all candidates... Peter Alfke, Xilinx Applications

You might also want to talk with Actel, as a GTO chopper is not likely to have massive gate counts, but you WILL want fairly quick power up, and high EMC immunity levels. What sort of standards and guarantees do you have to meet ?

-jg

Considering he is from .ru and its winter, he just needs to leave it outside overnight.

Sander +++ Out of cheese error +++

When I went to work this morning it was -18 °C (I live in Oslo, Norway). Russia is usually a bit colder.

Petter

A: Because it messes up the order in which people normally read text. Q: Why is top-posting such a bad thing? A: Top-posting. Q: What is the most annoying thing on usenet and in e-mail?

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