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See you all Thursday

Iron

@Randy: I was talking about followon production contracts where the decision is to build more of the same unit, knowing a component is near End-of-Life vs redesign of the unit with a new sensor. Though, a lifetime buy would be based on this being the last followon contract. I have had contracts that have gone on for dacades and have been thru several redesigns due to sensor EOL.

Iron

Thanks Randy, Lauren & Digi-Key

Iron

*"the rule against putting a pressure sensor closer than 5 pipe diameters to any obstruction, valve, etc?"* Pressure is Pressure. It's the same everywhere. UNLESS you change inside diameters. Turbulence is an issue for flow, however.

We measure pressure on axial piston pumps, which results in Pulsation. This can damage a sensor. It certainly damages bourdon tube gauges. We get a sensor with an integrate snubber, and provide an external snubber as well.

Iron

Thank you Randy for another great lecture. Signing out. Have a great day.

Iron

lynnbr 2,  Good way to go.  It is important to do this early on before you are locked into a specific product.

Iron

I built a mechanical test rig using a Hydraulic hand pump and a custom manifold. I tested four pressure sensors concurrently with a bourdon tube gauge as a fifth device, Very interesting to compare actual samples form different manufacturers side-by-side!

Iron

Thanks, everyone. That's going to do it for today.

Blogger

@Randy  How seriously do you take the rule against putting a pressure sensor closer than 5 pipe diameters to any obstruction, valve, etc?  How about the rule to avoid long stubs and mount as close to flush to the pipe wall as possible?  Can you give an order of magnitude estimate of the accuracy sacrifice for violating these "rules"?

I'll have to claim ignorance in this area. My experience is in the electrical side. My usual approach is to trust the rule of thmb until its proven wrong or not applicable to the specific application.

Blogger

Thanks, Randy, Lauren, Design News, and Digi-Key.

What is the diffference betewwn operating and accuracy pressure? in spec's.

Accuracy found on a supplier's data sheet is within the operating pressure range. Outside of that range, there is no guarantee.

Blogger

Interesting topics.  Thanks Randy

Iron

In my humble opinion decreasing cost comes after preliminary evaluation.

tests, consistency and reliablite comes first

Iron

I certainly would not start out in a lifetime buy situation.  If you had been using the product for years, and had confidence in it, then a lifetime buy makes sense.

Iron

I built a mechanical test rig using a Hydraulic hand pump and a custom manifold. I tested four pressure sensors concurrently with a bourdon tube gauge as a fifth device, Very interesting to compare actual samples form different manufacturers side-by-side!

Iron

@Randy: Would you need to predicate your selection process on the possibility of having to cost a Lifetime buy for a sensor that has been on the market for several years?

 

I tried to consider more common application requirements today. Lifetime buy is among the aspects that can make the decision process much more complex. That usually involves a discussion with the supplier or the distributor.

Blogger

At the risk of sounding old fashioned I find it interesting regarding searching for product you do not even mention trade shows, conferences or other face to face opportunities.

Those certainly help to make sure you ultimately make the right choice but I'd rather not spend the airfare and time without doing  a little checking on my own.

Blogger

Helpful info. Thanks Randy!

Iron

@Randy: Would you need to predicate your selection process on the possibility of having to cost a Lifetime buy for a sensor that has been on the market for several years?

Iron

@Randy  How seriously do you take the rule against putting a pressure sensor closer than 5 pipe diameters to any obstruction, valve, etc?  How about the rule to avoid long stubs and mount as close to flush to the pipe wall as possible?  Can you give an order of magnitude estimate of the accuracy sacrifice for violating these "rules"?

?What maybe is not clear is that it is possible to buy a temperature compensated sensor (passive components) at a low price.  That is the type of calibration you do not want to have to do.

Iron

If I have the luxury of time I would prefer to do my own.

Iron

@Randy Quest. What is the diffference betewwn operating and accuracy pressure? in spec's.

Iron

?Randy, you have not stressed cost as an issue.  In cost sensitive applications, you may be able to get away with a $5 sensor and your electronics instead of paying $110.

Iron

Would you prefer a sensor with built-in signal conditioning or do you want to add the signal conditioning to your design?

It depends on requirements, but when it is possible I prefer sensor with built-in signal conditioning

built-in signal conditioning  or not :
depends on system design ; might need or might not

Iron

Thanks Randy and Lauren

Iron

Advertisements in trade magizines is also sometimes useful in finding a supplier.

Iron

Those AFE chips are interesting. It is especially how technology similar to FPGA - or, more technically, FPAA - is entering more more and more market segments.

Iron

Like IACyclone mentioned ; after finding a part, need to go to manufacturer web site for latest datasheet, last-time-buy info, App Notes, etc.

Iron

Randy, would you build a "boilerplate" test platform to test the chosen pressure sensor? Check such things as basic accuracy, frequency response, what happens under illegal operating conditions, such as pressure excursions beyond your range of interest?

These are certainly key items in a thourough selection and qualification process. Frequency repsonse was not a criteria in today's selection but in some applications it is one of the more critical design aspects.

Blogger

What gotchas have you found in searching for potential products and suppliers?

First, think of what features of sensor you need, then make an strategy to find the product that matches your idea.

 

Is there any way to find out what experience other users of a particular sensor or sensor family may have had? If another customer had a high failure rate, that would be nice to know. Doubt the sales people would volunteer that info...

Thanks to everyone!

Iron

Thanks Randy and Lauren.

Iron

@Randy, Thanks for the lecture Is TI's WEBENCH bundled with TI's Labview or is it seperate

I am not aware of a bundling with  NI's LabView

Blogger

Thanks, Randy and Lauren

Norm EVM are 250$ 

Iron

Randy, would you build a "boilerplate" test platform to test the chosen pressure sensor? Check such things as basic accuracy, frequency response, what happens under illegal operating conditions, such as pressure excursions beyond your range of interest?

Thank you Randy & Digi-Key!

Iron

Randy, slide 20.  Does the "Device Error" refer to the error in the sensor or in the error in the signal conditioning chip (LMP90100)?  6% seems too high to be the LMP90100.

can you provide links to any pre-reading that would be good to read prior to class?

I was hoping that the links in either the slide or the notes portion woukd lead you to preread material. Today's slides do not have that many links.

Blogger

That AFE is an interesting chip - makes me want to design something with it even though I don't need to at the moment.

Iron

Thanks.  Randy - digikey should be paying you well for that presentation.

Iron

Thank you Randy and Lauren

Iron

@DWSY, did you see the items under Educational Resources at the right of the screen?

Gold

Thanks Randy and Lauren. Kudos to content, style, and length.

Iron

Randy, what are other search options (i.e. web sites, ect) that we may want to be aware of?

Iron

great presentation, we were thinking of an interface to a pressure sensor. This helps. Thank you

Iron

Thanks Randy and Lauren.  Thanks everyone.

@Randy, Thanks for the lecture Is TI's WEBENCH bundled with TI's Labview or is it seperate

Iron

Thanks Randy and Lauren

Iron

When a company acquires another  company, lot of  sensors becomes obsolete as the new company stops few of the product lines, very difficult to find potential replacement  for those

Iron

Thank you Randy, Lauren and Digi-Key

Thanks good concepts.

 

Iron

Very informative Randy.

Iron

Thanks Lauren and Randy!  Good job.

thank you Lauren and Randy

Iron

Thank you Randy and Lauren

Thanks Randy and Lauren

Iron

Thanks,  Very helpful

Iron

Thanks Randy.  Informative session

Thanks Randy and Lauren.  Good stuff today.

Thank you Lauren, thank you Randy

Thanks Lauren and Randy

Iron

Thank you Randy and Lauren.

Iron

can you provide links to any pre-reading that would be good to read prior to class?

Iron

Thanks Randy and Lauren.

Iron

Thank you,

Lauren, Randy

Iron

Thank you Randy, Lauren, and Digi-Key

Gold

Thank you Lauren and Randy.

Iron

Thanks Randy and Lauren

Iron

At the risk of sounding old fashioned I find it interesting regarding searching for product you do not even mention trade shows, conferences or other face to face opportunities

Iron

We are on slide 22. 

Platinum

I find these lesson to be very imformative but more research must be done on my side to evaluate the uses for these products

Iron

We are on slide 21. 

Platinum

I would like built in signal conditioning

Iron

Frequency response is also important.  Because you can low pass to eliminate noise, but it costs you frequency response.

Iron

suppliers are identified through associates, internet searches, past experience.  Cold calls rarely helpful.

Iron

We are on slide 20. 

Platinum

Do you have another approach that you use to identify a potential supplier?

Ask a friend, an expert, consult Internet sor ome documentation

Built in conditiong

Iron

I want to add the signal conditioning to my design?

 
 
Iron

depends on requirements, built in would be first preference

Iron

the letter case is my favorite.  I want to add some kind of signal conditioning for my design.

Iron

add conditioning away from battery-powered sensor to reduce power needs

 

Iron

I may do the signal conditioning if I needed special CMRR of Noise filtering, as an example

Iron

built in signal conditioning is prefered .

Iron

For low cost (disposable) I want passive compensation in sensor.  For gaging, I want electronics (buffering and amp) in sensor.

Iron

We are on slide 18. 

Platinum

Usually do my own conditioning because there is so much variance with aplication

Iron

I prefer build-in for reducing EMI issues

built-in is preffered

Iron

Prefer to add signal conditioning

Iron

partly depends on what I/O is or will be available on on the host -  i.e. any analog inputs, vs digital only, or I2C, SPI, etc.  

Iron

INdded, we prefer a sensor with buil in conditioning

Chosing built-in vs. designed conditioning depends on the application and expected final product volume.

Iron

Want to control what cnditioning is added

Iron

Depends on time of project and reliability of pressure device.

Iron

Prefer built-in conditioning

Iron

I would exhaust the built in capabilities before doing the signal conditioning myself

distance to the sensor from the electronics package is a big consideration.

Iron

Depends on the application.  For a remote sensor, I would be more inclined to want built in so that a low level signal doesn't have to be dragged all across the plant.

preferably built in signal conditioning that could offer better noise resistance and direct digital readings through serial interface

 

Iron

Since I mostly build prototypes, I prefer as many integrated/built-in functions in my modules as possible. Don't try to solve too many detailed problems at once; prove the concept first.

Iron

We are on slide 17. 

Platinum

built in is nice but it usually comes down to application needs and cost

Iron

Prefer a sensor with built-in signal conditioning.

Iron

built-in for simplicity

Iron

Prefer built-in signal conditioning most of the time.

Iron

I like not having to do the conditioning myself.

Iron

It depends, i.e., conditioning on a case-by-case basis.

Iron

built in for most part

Iron

prefer built-in signal conditioning

I usually need to design my own signal conditioning circuits

I usually prefer built-in signal conditioning.

Iron

no built in signal cond

Iron

Prefer as much buit in as possible -- the less work the better!

Iron

built in signal conditioning

Iron

 built in signal conditioning

Iron

Vastly prefer built-in signal conditioning.

Iron

built in signal conditioning

Iron

I like built in for interface simplicity

Iron

Randy's question was: Would you prefer a sensor with built-in signal conditioning or do you want to add the signal conditioning to your design?

Platinum

Few are approved class 3 or military/aerospace. keeo to major players, Honeywell and amphenol

Iron

Digi-key's database look ok.

After the pressure range, what is your most important consideration for selecting a sensor?

Acuracy, integration level, price

length of life of components

Iron

We are on slide 15. 

Platinum

I go with digikey too

 

Iron

nothing major gotchas...digi-key database is pretty good

Iron

Gotchyas usually ambiguity in specs.   engineer emptor

Iron

Unavailable parts. Not clear if simply out of stock or not yet available.

Iron

Unbearable lead times

Iron

I have come across pinout typo that resulted in parts burning up on the board because power was on wrong pin.

Iron

Sure. I've found typos in datasheets.

Iron

mainly spec ranges, like the temp example, where a part may exceed your min requirement but the search does not match.

Iron

Oh, and minimum quantity of order. Only need one, can only get 10,000.

Iron

somo distributors don't have all the data display. Digi-key's database is pretty good.

Iron

Having choices that are overwhelming.  It can be hard to narrow down the choices.

typs are used where i wanted max/min

Iron

We are on slide 14. 

Platinum

Biggest problem is items not in stock

Iron

Design with best on the market then explore the aternate cost effective

Iron

inadequate search criteria for some things. for example this list doesn't include media of the pressure value being measured. might choose something for meauring air when you want to measure oil or water.

Iron

Nothing major.  Digi-Key's search is amazing.

Iron

Some items are actually special order

Iron

Yes, Need to always review order documentation and manuals.

Iron

yes, gotya on temp range etc.  but you can usually select multiple options by using the control key while you select.

Iron

not always linked to the most recent datasheet for a part - sometimes specs change due to errata found during development which are very important and not always reflected in the distributers seach terms.

Iron

inconsistencies in information provided

Iron

I find occasional typos but usually have good luck with these searches

Setting too specific search parameters too soon often returns zero results. Add search criteria one at a time to get to a reasonable list of parts. Then visual examination of thumbnails works wonders.

Iron

I have noticed the same:  too narrow of a search may leave out what youre really looking for

Iron

In stock versus long lead times

I have not encountered any search problems to date.

Iron

Capacitor searches can be tough.

Iron

lead time, in-stock and non-stock

Iron

Sometimes the table data disagrees with fine print in the datasheets.

Iron

Some parts have a minimum order quantity

Gold

Randy's question was: What gotchas have you found in searching for potential products and suppliers?

Platinum

I really miss having a downloadable catalog from Digi-Key!

This way you can scan a family of parts much easier, once the search gets you in the range.

Iron

We are on slide 12. 

Platinum

I normally due digikey

Iron

Hello from Pittsburg

 

Iron

Stay with the majors

Iron

We are on slide 10. 

Platinum

I might ask a friend but web would be hi on list.

Iron

Start with distributor. Move on to spec sheets.

Talk with sales

Sometimes talk to rep.

Iron

Going through design history files of prior products

 

Iron

new tech emails from manufacturers, suppliers, etc...

Iron

Sometimes suppliers can be acquired by recommendation from application notes or reference designs or previous applications of others.

Iron

purchasing department expert

Iron

datasheets from google search. use past distributors parts search engines

Iron

We are on slide 9. 

Platinum

I look at products being manufactured to see what is used by them.

Iron

Ask colleagues (that may have worked at competitors)

Iron

I look to see what characterization data is provided

Iron

web search, previous supplier inquiry

Iron

Advertisements in trade magazines.

Iron

Your suggestions look good

Gold

No other approach. Just looots of googling :D

We are on slide 8. 

Platinum

I usually call a local rep.

oh and a digikey or newark search

Iron

Work with Mfr's reps

 

Iron

Knowledgeable distributor sales/tech support personnel recommendations.

Iron

Ask a question in one of the groups on LinkedIn

Iron

Sometimes trade shows are useful.

Iron

Generally Distributor and technical articles

Iron

consult with purchasing

Company inventory... (previous BOMs)

Iron

Search company history and parts lists from other systems

Iron

Basic internet searches

Iron

Randy's question was: Do you have another approach that you use to identify a potential supplier?

Platinum

@Ferrero

¡Hola paisano!

 

Iron

accuracy, reliability, repeatability

Iron

@Lauren: the slide numbers are off by 1 just started slide 6

Iron

go to Digi-Key, of course

 

Iron

We are on slide 7. 

Platinum

Temperature range is second to pressure range.

We are on slide 6. 

Platinum

It's ability to survive in a harsh environment ie Hi corrosion, dust &  water contamination, human abuse

Accuracy, repeatability and life expectancy

Iron

Depends on the application but I guess relevant to the importance it would be temeprature range

Iron

hello, sorry I'm late

Iron

Cost, precision accuracy

Iron

The most important parameters are: range, resolution

Linearity ; sensor package ; electrical supply range ; pricing

Iron

Cost is usually an important consideration

Temperature Range, Package, output value all pretty equal

 

Iron

Accuracy and repeatability

Sensor selection criteria:  size/package, availability, price

Iron

accuracy and linearity, then package

Iron

Interface to downstream hardware/software, e.g. protocol, physical layer etc.

Iron

accuracy, stability and resolution

Iron

medium (type of gas/fluid), accuracy

Temperature: some are -40C to 85C while others go 55C to 125C

Iron

After pressure, I need to consider the temperature range, then the media.

precision, temperature range

Iron

Accuracy without having to do a separate calibration.

Iron

Temperature and resistance to water and sunlight

Gold

reliablility, accuracy and interfacing

Iron

Normally temperature range and accuracy.

Iron

Hello from W. Caldwell NJ

Iron

after range reliability and accuracy

Iron

After pressure, package is most important.

Iron

Randy, automotive temp range should start at -65

hello from Mishawaka

Iron

Randy's question was: After the pressure range, what is your most important consideration for selecting a sensor?

Platinum

Hi from Goiania, GO, Brazil

Iron

Hello forem culiacan mexico

Hello from sunny SE Lake Simcoe Ontario Canada.

Iron

Hi from Rocklin, CA

 

Iron

Cool. Smart sensing is one of the main reasons I was interested in this course.

Iron

Greetings from Somewhere on the Niagara Frontier.

Iron

Hello from Albuquerque

Hello from sunny Montreal

Iron

Hello from Austin, TX

 

Iron

Hello from Upstate NY!

Iron

Hi all -Audio is live! If you don't see the audio bar at the top of the screen, please refresh your browser. It may take a couple tries. When you see the audio bar, if it doesn't start automatically, hit the play button. If you experience audio interruptions and are using IE, try using FF or Chrome as your browser. Many people experience issues with IE. Also, make sure your flash player is updated with the current version. Some companies block live audio streams, so if that is the case for your company, the class will be archived on this page immediately following the class and you can listen then. People don't experience any issues with the audio for the archived version.

Hello from Chicago

Iron

Hello from Longmont, CO

Iron

Good morning from Calgary

Hello from SW Michigan

Iron

Hello from Corona ca

Iron

Hello from Co Springs!

 

Iron

Greetings from Saginaw, MI

Hello from Cedar Park TX

Iron

Good afternoon from Minnetonka, MN.

Iron

Hello from the San Francisco Bay Area

Iron

Hi Randy, Good afternoon from Boston, MA

Hello from Montana

Gold

Hello from pleasant Spokane, WA

Iron

Hello from sunny Beavercreek, OH

Hello from Thornville, Ohio

Iron

Hello from Albuquerque.

Iron

Hello from Montreal, QC - staying in Canada as of Monday ;-)

Iron

hello everyone from Timisoara, Romania

Iron

Hello. Today's session is one of my favorites.

Blogger

Howdy from Corinth, Texas!

hola desde SOCAL/mexifornia

Iron

Hi Lauren and Randy. How are you too? I am looking forward for another great lecture

Iron

How is everyone doing today?

Iron

Hello from Summerville, SC

Iron

Great weather in Rochester, ny.  Somebody made a mistake?

Hi all.

Iron

You are eligible to earn IEEE Professional Development Hours by attending these courses and participating in the chat function. Additionally, we are no longer using the points system, offering "graduation", or giving grades. The IEEE hours are taking the place of that. There are some important things for you to know about earning the hours. The most important ones are that you need to attend these courses live, you need to attend a minimum of two of them per semester, you need to fill out a course evaluation form within 2 weeks of the end of the class, you need to attend 4 out of the 5 classes per course, and you need to participate in the chat function every day you attend. Please click on the link at the top of this page that says "How do I earn IEEE professional development hours" to read all of these important details and more.

Platinum

Hello from Kansas City, Missouri.

Greetings from Plymouth, MN!

Iron

Good Afternoon from Valladolid, Spain, Iberic Penninsule.

 

Iron

Supposed to get nice today here in Iowa.

Iron

yet another Gorgeous day - in Houston !

Iron

Howdy from Tomball, TEXAS!

Iron

Please join our Digi-Key Continuing Education Center LinkedIn Group at http://linkd.in/yoNGeY and be sure to follow @designnews and @DigiKeyCEC on Twitter for the latest class information. We encourage you to tweet about today's class using #DigiKeyCEC.

Platinum

Good morning from Edmonton, AB

Iron

The streaming audio player will appear at the top of this web page when the show starts at 2 PM Eastern time today. When you see it, click on the play button to start the audio. Note however, that some companies block live audio streams. If when the show starts, the audio bar doesn't appear or you don't hear any audio, try refreshing your browser. If that doesn't work, try using Firefox or Google Chrome as your browser. Some users experience audio interruptions with IE. Also, make sure your flash player is updated with the current version. If that doesn't work, the class will be archived immediately following our live taping. You shouldn't experience any problems with the audio when listening on-demand.

Platinum

Be sure to click 'Today's Slide Deck' under Special Educational Materials above right to download the PowerPoint for today's session.

Platinum

Greetings From Ghana @ Work

Iron


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