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Opinions re: MCU vendors

Started by D Yuniskis January 17, 2010
[crap!  I meant to crosspost this here and s.e.d  :< ]

Hi,

I'm looking at a couple of different parts from Atmel
and TI for an upcoming design.  I'd appreciate comments
(not *rants*) folks might have about both firms in terms
of:
- quality of their products
- accuracy of their documentation
- ability to meet commitments
- responsiveness during the design process
etc.

I often have to approach vendors as a "one man shop" during
product development with production buys done by clients
*after* the design is finished.  So, I usually can't carry
the clout that their buying power will (NDA's).

And, I tend to use devices in unusual ways  :>  So, I tend
to end up digging around in dark corners of implementations
uncovering things that they didn't expect (or *know*) would
ever occur.  This is particularly important nowadays when
everything is spec'ed with "typical" numbers and damn few
"worst case" numbers ("Yikes!  The power supply went into
current limit!  I guess the *real* power consumption is
considerably more than the 'typ' figures you guys published...")

I.e., I don't want to waste time with firms that are either
slow to respond to *highly* technical inquiries (in the past,
I've had face-to-faces with the actual designers of many
components that I've "stetched" in unusual ways) or simply
brush them off thinking it's not worth their time/effort
(Motogorilla has lost *many* designs over the years on account
of this).

Thanks!
--don
On Jan 18, 11:19 am, D Yuniskis <not.going.to...@seen.com> wrote:
> [crap! I meant to crosspost this here and s.e.d :< ] > > Hi, > > I'm looking at a couple of different parts from Atmel > and TI for an upcoming design. I'd appreciate comments > (not *rants*) folks might have about both firms in terms > of: > - quality of their products > - accuracy of their documentation > - ability to meet commitments > - responsiveness during the design process > etc. > > I often have to approach vendors as a "one man shop" during > product development with production buys done by clients > *after* the design is finished. So, I usually can't carry > the clout that their buying power will (NDA's). > > And, I tend to use devices in unusual ways :> So, I tend > to end up digging around in dark corners of implementations > uncovering things that they didn't expect (or *know*) would > ever occur. This is particularly important nowadays when > everything is spec'ed with "typical" numbers and damn few > "worst case" numbers ("Yikes! The power supply went into > current limit! I guess the *real* power consumption is > considerably more than the 'typ' figures you guys published...") > > I.e., I don't want to waste time with firms that are either > slow to respond to *highly* technical inquiries (in the past, > I've had face-to-faces with the actual designers of many > components that I've "stetched" in unusual ways) or simply > brush them off thinking it's not worth their time/effort > (Motogorilla has lost *many* designs over the years on account > of this). > > Thanks! > --don
One simple litmus test, is to look at the Errata sheets, and also confirm the target device is actually in real production. - and feel free to ask a 'test question' ;) DY: [And, I tend to use devices in unusual ways :>] Hehe, doesn't everyone do that to some extent!!. It's true that average data sheets have gone backwards in information, and so getting a low cost Eval board, is often more important than the data. There is no real substitute for actual working silicon, as a reference point. Example: I wanted to know the Transistion current of a device (Icc vs Vin) on a digital pin. You'd be dreaming to ask that via the average support channels [The what?] - so faster to just measure a device. -jg
On Jan 17, 2:19=A0pm, D Yuniskis <not.going.to...@seen.com> wrote:
> > And, I tend to use devices in unusual ways =A0:>
Like Jim said, we all do that :-). That's what we do for a living, I guess.
> I.e., I don't want to waste time with firms that are either > slow to respond to *highly* technical inquiries (in the past, > I've had face-to-faces with the actual designers of many > components that I've "stetched" in unusual ways) or simply > brush them off thinking it's not worth their time/effort > (Motogorilla has lost *many* designs over the years on account > of this).
I can only speak of Motorola (Freescale) and TI, never used Atmel processors. My experience with TI is almost 10 years old now - but back then I was considering their 5420 DSP. They sent me the data on paper for free (one of the books is still valuable as it carries a few notes I penciled over some opcodes when I was implementing the assembler...), but they were just horrible when it came to getting prototype quantities. They had nothing at distributors. The support person I was in contact with told me "we cannot send you any free samples as the part is too expensive, and we cannot sell you that small a quantity". Terrific. This was at the time their silicon was at revision D or E, mind you. A friend of mine in the US had friends who used the part and sent me some (the part is not easy to replace in this design to this day, their tech support engineer said I would have no chance to make it work... OK, he did not know me so he can't be blamed). ( http://tgi-sci.com/tgi/hstb.htm ) With Freescale, it has been easier for me to get in touch with some guy either involved with the design of the part I use or someone who knows someone etc.; getting data under NDA has also worked. But going through the direct channels will be no better than TI, I am pretty sure. Generally I have learned to make my choices based on technical and price reasoning (the latter has rarely been important, I don't design many mass-consumer products) and part survival expectations/gut feeling; one way or the other one can get the needed data - even from a place like Bulgaria. Perhaps the worst adviser when making a choice can be some unpleasant experience with sales or support personnel, one should simply keep being above all the usually related nonsense. Dimiter ------------------------------------------------------ Dimiter Popoff Transgalactic Instruments http://www.tgi-sci.com ------------------------------------------------------ http://www.flickr.com/photos/didi_tgi/sets/72157600228621276/ Original message: http://groups.google.com/group/comp.arch.embedded/msg/274= 2a811511142b9?dmode=3Dsource
"D Yuniskis" <not.going.to.be@seen.com> wrote in message 
news:hj01re$f5l$1@speranza.aioe.org...
> [crap! I meant to crosspost this here and s.e.d :< ] > > Hi, > > I'm looking at a couple of different parts from Atmel > and TI for an upcoming design. I'd appreciate comments > (not *rants*) folks might have about both firms in terms > of: > - quality of their products > - accuracy of their documentation > - ability to meet commitments > - responsiveness during the design process > etc. > > I often have to approach vendors as a "one man shop" during > product development with production buys done by clients > *after* the design is finished. So, I usually can't carry > the clout that their buying power will (NDA's). > > And, I tend to use devices in unusual ways :> So, I tend > to end up digging around in dark corners of implementations > uncovering things that they didn't expect (or *know*) would > ever occur. This is particularly important nowadays when > everything is spec'ed with "typical" numbers and damn few > "worst case" numbers ("Yikes! The power supply went into > current limit! I guess the *real* power consumption is > considerably more than the 'typ' figures you guys published...") > > I.e., I don't want to waste time with firms that are either > slow to respond to *highly* technical inquiries (in the past, > I've had face-to-faces with the actual designers of many > components that I've "stetched" in unusual ways) or simply > brush them off thinking it's not worth their time/effort > (Motogorilla has lost *many* designs over the years on account > of this). > > Thanks! > --don
I've always had good support on tech stuff direct from Atmel. Ther is also a huge support forum- avrfreaks.net
-jg wrote:
> On Jan 18, 11:19 am, D Yuniskis <not.going.to...@seen.com> wrote: >> [crap! I meant to crosspost this here and s.e.d :< ] >> >> Hi, >> >> I'm looking at a couple of different parts from Atmel >> and TI for an upcoming design. I'd appreciate comments >> (not *rants*) folks might have about both firms in terms >> of:
<snip>
> > One simple litmus test, is to look at the Errata sheets, and also > confirm the target device is actually in real production.
You say look at the errata sheets, but don't say why. Is a small errata the sign of a quality product, or a dishonest vendor. Or simply that the part is too new for the bugs to have surfaced? Is a long errata the sign of a bad product, or an honest helpful vendor that is trying to prevent you wasting time on known bugs? I think you have to know the company well *before* you can come to conclusions simply by looking at the errata. -- Regards, Richard. + http://www.FreeRTOS.org Designed for Microcontrollers. More than 7000 downloads per month. + http://www.SafeRTOS.com Certified by T&#2013265948;V as meeting the requirements for safety related systems.
On Jan 17, 5:19 pm, D Yuniskis <not.going.to...@seen.com> wrote:
> Hi, > > I'm looking at a couple of different parts from Atmel > and TI for an upcoming design. I'd appreciate comments > (not *rants*) folks might have about both firms in terms > of: > - quality of their products
That is a pretty poorly defined metric. It reminds me of the Volvo commercial many years ago when the US makers were still building crap. It was a huge presentation room with hundreds in the audience. The speaker talked about quality and then started chanting, "Quality, Quality,..." and the audience started chanting with him. The point was that the US makers were just chanting quality without doing anything measurable. But then quality is not a measurable thing. Can you tell me what you mean by quality? Can you define it in some terms that someone else could respond in a way that would have meaning to you?
> - accuracy of their documentation
My experience is that both Atmel and TI have quality documentation. TI seems to be less willing to modify their documentation if you have questions it does not answer. Once I got Atmel to add some info to their SAM7 data sheets to define crystal requirements. But then they provided a table with data points at specific frequencies that didn't say what to do in between. I pointed out the issue and they wouldn't even comment verbally much less clean up the issue. So I still think they are about equal.
> - ability to meet commitments
I like this one. What sort of commitments are you talking about? Production? Updates? Support? If you are a small player, don't expect too many commitments in the first place, much less holding to them. All IC makers have a handful of major customers for whom the sun rises and sets. Everyone else in secondary or even tertiary.
> - responsiveness during the design process
Again, I have not found a significant difference between the two companies. I have found the occasional FAE who is exemplary. I've had a TI FAE who would walk across burning coals (he's no longer with TI unfortunately). My current Lattice FAE is pretty durn good although I think he would want to good pair of boots before the walk on coals. I want to say all the support I've gotten from Atmel was through distributor FAEs and was other than great. Disti FAEs are typically trained in many product lines from many makers and just don't have the time to dig into them all in detail. But they can be helpful in getting the ear of the factory support people. So you need to gauge your local FAEs yourself.
> etc. > > I often have to approach vendors as a "one man shop" during > product development with production buys done by clients > *after* the design is finished. So, I usually can't carry > the clout that their buying power will (NDA's).
I use contract manufacturing and get the same result. If you aren't buying your own parts, it is much harder for the support people to get credit for your orders, assuming you have any. In your situation, you will be invisible or nearly so. It helps if you customer's procurement people are willing to cooperate. But you need to get them in the loop with your local salesperson. Of course this is a PITA, but it helps to get credit to the right people and I think they really appreciate it.
> And, I tend to use devices in unusual ways :> So, I tend > to end up digging around in dark corners of implementations > uncovering things that they didn't expect (or *know*) would > ever occur. This is particularly important nowadays when > everything is spec'ed with "typical" numbers and damn few > "worst case" numbers ("Yikes! The power supply went into > current limit! I guess the *real* power consumption is > considerably more than the 'typ' figures you guys published...") > > I.e., I don't want to waste time with firms that are either > slow to respond to *highly* technical inquiries (in the past, > I've had face-to-faces with the actual designers of many > components that I've "stetched" in unusual ways) or simply > brush them off thinking it's not worth their time/effort > (Motogorilla has lost *many* designs over the years on account > of this).
Yep, if they can't see the dollars, they don't respond very well. Isn't that true of us all? All in all, I don't think you will see a big difference between Atmel and TI. I think Atmel will be slightly better in terms of support. But it also depends on the products. If you are looking at the CM3 CPUs, TI doesn't make them. They've bought Luminary Micro and I think much of LM still works the same as it did. So you would need to check out LM as a distinct entity from TI. Rick
rickman wrote:
> On Jan 17, 5:19 pm, D Yuniskis <not.going.to...@seen.com> wrote: >> Hi, >> >> I'm looking at a couple of different parts from Atmel >> and TI for an upcoming design. I'd appreciate comments >> (not *rants*) folks might have about both firms in terms >> of: >> - quality of their products > > That is a pretty poorly defined metric. It reminds me of the Volvo
It is poorly defined only in the sense of how it is *measured*. But, you *know* a quality product when you see it. You also know *crap* when you see that!
> commercial many years ago when the US makers were still building > crap. It was a huge presentation room with hundreds in the audience. > The speaker talked about quality and then started chanting, "Quality, > Quality,..." and the audience started chanting with him. The point > was that the US makers were just chanting quality without doing > anything measurable. But then quality is not a measurable thing. Can
Sure it is! Perhaps not in some "internationally acceptable interchangeable unit of measurement". E.g., I spent a few summers working for a (huge) hand tool manufacturer. Part of my job was quality related. Judging the quality of their current products and how they compare to other manufacturers of hand tools. Tell me, how do you *measure* the quality of a hammer? A screwdriver? A tape rule? A saw?? First, you verify it meets all of your mechanical specifications. E.g., what is the draft angle of the two faces of the (slotted) screwdriver's tip? If it is a "cabinet tip" screwdriver, are the *sides* of the tip parallel? Are the flutes in a Phillips screwdriver free of buildup from the plating process? Are the markings on a tape rule legible and accurate? Second, you verify that it meets the other design specifications. E.g., what is the (Rockwell) hardness of the shank? How thick is the plating? Third, you verify that it meets the appropriate "bogo-units". E.g., if the shank is held fast, how much torque is required to "strip" the handle off of the shaft? If the screwdriver tip is pushed into a precision die with a force of X, how much torque is required to *sheer* the tip off? How many times can you "bang" a hammer before the handle fails? Of course, the third group are, by far, the most fun to devise and implement. They are somewhat arbitrary. Bogus. Yet, they each pertain to QUALITY FACTORS that the USER WILL PERCEIVE. Ever been pissed off because you *tore* the tip off a Phillips screwdriver? (the average man can do this *easily* for a #0 screwdriver, "with some effort" for a #1, and "only if really determined to do so oand with the assistance of leverage enhanceers" for a #2. #3 requires hydraulic assistance. :> ) Notice how *long* the finish on a tape rule lasts? Despite the fact that it is *continuously* experiencing friction? Ever wonder why the plastic case on that 25' tape rule doesn't shatter when the tape retracts from its full extension? How do we measure quality in *software*? Count the number of bugs? Are all bugs of equal "value" (within an application -- lets ignore the complication of dealing *between* application domains)? I was drawing a schematic last night. The "part editor" has a bug in it that causes placement of pins not to track the cursor's position. Annoying. OTOH, abandoning a newly created schematic sheet causes the application to *crash*. Potentially very expensive! And, for the most part, we don't even have a deterministic way of *testing* software -- at least I can set up a machine to bang a hammer continuously until it breaks! (whatever a "bang" unit happens to be)
> you tell me what you mean by quality? Can you define it in some terms > that someone else could respond in a way that would have meaning to > you?
Sure, obvious things: - parts failing to meet their published specification (you would agree that this would be "crap"?) - parts that *technically* meet their published specification but not "in good faith". Especially nowadays with datasheets full of "typ" numbers. ("Yes, typically Icc is 10mA. The fact that *all* of the devices you have purchased from us draw 100mA is still within the (unspecified) maximum that we publish for that part.") But, also, remember that their "product" isn't limited to bits of plastic made in the far east: - documentation that is grossly and obviously incorrect - errata that are not kept current and/or are "hidden" for fear that someone would "think ill" of their product I was reviewing an SiLabs part last week. Application data in the datasheet (sample schematic) had to be one of the worst drawn documents I'd ever seen! As if someone had pasted little *squares* (don't folks know that there are symbols for things like optoisolators? transformers??) on an Etch-a-Sketch and asked a two year old to "connect the dots". <frown> This document speaks for your (their) component. It is reproduced in perhaps 6 other app notes verbatum. So, each time you see it, you remember, "Oh, crap. Not this again..." Documentation for a reference design using that same component had obvious flaws in the schematic. "What did you guys use to layout the *board*? Why publish anything other than the *actual* schematic that drove your PCB layout tool??" Sure, these are nits. But, everyone who reads these documents runs an increased risk of making a mistake *or* spending extra time to sort out what is *really* intended in the documents. Presumably, they would want customers to have *success* with their products. This suggests they would want to do everything reasonably possible to facilitate that success (proofreading a document doesn't seem to be a *huge* undertaking!). So, if something like this that is in *their" "best interest" is treated so casually, what does that suggest about the "quality" of their silicon? their support? etc.
>> - accuracy of their documentation > > My experience is that both Atmel and TI have quality documentation. > TI seems to be less willing to modify their documentation if you have > questions it does not answer. Once I got Atmel to add some info to > their SAM7 data sheets to define crystal requirements. But then they > provided a table with data points at specific frequencies that didn't > say what to do in between. I pointed out the issue and they wouldn't > even comment verbally much less clean up the issue. So I still think > they are about equal.
It seems that manufacturers are moving more into just becoming foundries -- or IP houses (ARM). Trying to get a mix between them seems to be difficult.
>> - ability to meet commitments > > I like this one. What sort of commitments are you talking about?
Wanna buy a Z380? :>
> Production? Updates? Support? If you are a small player, don't > expect too many commitments in the first place, much less holding to > them. All IC makers have a handful of major customers for whom the > sun rises and sets. Everyone else in secondary or even tertiary.
Of course! I've bought components "by the pound". And, size shouldn't affect their *ability* to meet their commitments. When I'm buying 1M of a particular device / year, I have a different level of expectation (tell me I have to wait 3 years and I'll smile and turn a new crank on thedesign so your name isn't on any of the components). When I'm buying 1K of that same device / year, I *don't* expect the same *timeliness* of a commitment -- *but*, if you tell me 18 weeks, then I expect it to *be* 18 weeks and not 24 weeks or 36 weeks or "gee, your request must have got lost in the cracks"! I.e., I expect a vendor to cater to a (known) bigger client more promptly (allocation, etc.) than a small fish. But, I expect him to meet those commitments (that *he* is defining!) equally. E.g., I expect a banker to kiss the ass of someone with $1M on deposit. Walk in the door and perhaps he even gets up and holds your chair for you, etc. OTOH, someone with $100 in a savings account maybe can HELP THEMSELVES to a complimentary lollipop from the big candybowl at the teller's window. BUT I EXPECT EACH OF THEIR TRANSACTIONS TO BE PROCESSED WHEN PROMISED (maybe an instant wire transfer "on the house" for the big shot and "10 days" for the small fry)
>> - responsiveness during the design process > > Again, I have not found a significant difference between the two > companies. I have found the occasional FAE who is exemplary. I've
Agreed.
> had a TI FAE who would walk across burning coals (he's no longer with
I think these folks (i.e., the ones that are "good") tend to either have a ood work ethic or are engineers that crossed over into "support". I'm sure it must be a double-edged sword for them: on the one hand, you are free of the pressures of coming up with something "never done before" under a deadline; on the other, you never experience the depth of learning that requires; on the *other* other hand, you get exposed to a wider range of product ideas (which you can always mull over at your leisure without *having* to do so). For the right sort of person, it could be a dream job. For others, a nightmare.
> TI unfortunately). My current Lattice FAE is pretty durn good > although I think he would want to good pair of boots before the walk > on coals. I want to say all the support I've gotten from Atmel was > through distributor FAEs and was other than great. Disti FAEs are > typically trained in many product lines from many makers and just > don't have the time to dig into them all in detail. But they can be
Agreed. I've had friends who have outright told me that their goal is to "shmooze". Informal get-togethers (golf, ball games, etc.) with clients to build personal friendships -- the product isn't important. :< Makes you wonder what happens to those accounts when FAE Joe moves to another disti! :>
> helpful in getting the ear of the factory support people. So you need > to gauge your local FAEs yourself. > >> etc. >> >> I often have to approach vendors as a "one man shop" during >> product development with production buys done by clients >> *after* the design is finished. So, I usually can't carry >> the clout that their buying power will (NDA's). > > I use contract manufacturing and get the same result. If you aren't > buying your own parts, it is much harder for the support people to get > credit for your orders, assuming you have any. In your situation, you
Of course! I'll buy 100 pieces and they'll never hear from me again. They'll never (by design!) connect my efforts with larger purchases later on by Company X.
> will be invisible or nearly so. It helps if you customer's > procurement people are willing to cooperate. But you need to get them > in the loop with your local salesperson. Of course this is a PITA, > but it helps to get credit to the right people and I think they really > appreciate it.
In my case, that is what they *don't* want. Often, I design a product because a client doesn't want anyone to know they are looking into a particular market or product offering. As much as people like to *think* secrets are kept, you'd be amazed at how much "proprietary" information leaks out of sales reps, FAE's, etc. I have a client who loves to describe how he frequents sandwich shops (etc.) located near his competitors during the lunch hour and casually "reads his newspaper" -- all the while listening in to the banter going on around him (i.e., engineers and sales people from those firms chatting about work). Look how much you can discern on USENET about the types of products people are working on. Even if you *don't* know which firm employs them, etc.
>> And, I tend to use devices in unusual ways :> So, I tend >> to end up digging around in dark corners of implementations >> uncovering things that they didn't expect (or *know*) would >> ever occur. This is particularly important nowadays when >> everything is spec'ed with "typical" numbers and damn few >> "worst case" numbers ("Yikes! The power supply went into >> current limit! I guess the *real* power consumption is >> considerably more than the 'typ' figures you guys published...") >> >> I.e., I don't want to waste time with firms that are either >> slow to respond to *highly* technical inquiries (in the past, >> I've had face-to-faces with the actual designers of many >> components that I've "stetched" in unusual ways) or simply >> brush them off thinking it's not worth their time/effort >> (Motogorilla has lost *many* designs over the years on account >> of this). > > Yep, if they can't see the dollars, they don't respond very well. > Isn't that true of us all?
I like to think it isn't true of me! I try to do my best regardless of the size of the contract or the vendor. But, that's because I'm doing this "for me" and not just "for pay". <shrug> YMMV.
> All in all, I don't think you will see a big difference between Atmel > and TI. I think Atmel will be slightly better in terms of support. > But it also depends on the products. If you are looking at the CM3 > CPUs, TI doesn't make them. They've bought Luminary Micro and I think > much of LM still works the same as it did. So you would need to check > out LM as a distinct entity from TI.
Thanks for your comments! --don
Hi Dimiter,

Didi wrote:
> On Jan 17, 2:19 pm, D Yuniskis <not.going.to...@seen.com> wrote: >> I.e., I don't want to waste time with firms that are either >> slow to respond to *highly* technical inquiries (in the past, >> I've had face-to-faces with the actual designers of many >> components that I've "stetched" in unusual ways) or simply >> brush them off thinking it's not worth their time/effort >> (Motogorilla has lost *many* designs over the years on account >> of this). > > My experience with TI is almost 10 years old now - but back then > I was considering their 5420 DSP. They sent me the data on paper > for free (one of the books is still valuable as it carries a few > notes I penciled over some opcodes when I was implementing the > assembler...), but they were just horrible when it came to > getting prototype quantities.
Yes. I am especially wary of "new parts". I've bought plenty of vaporware over the years and have no desire to go down that road...
> They had nothing at distributors.
I have started to use Digikey as a barometer of whether or not I want to embrace a particular product. Yeah, its an arbitrary criteria and can hurt me just as much as help... but, you need *some* way of "sorting things"
> The support person I was in contact with told > me "we cannot send you any free samples as the part is too > expensive, and we cannot sell you that small a quantity".
"We can't discharge you unless you are insane. You must file the paperwork declaring your insanity. If you file the paperwork, you must be sane." (apologies to Mr. Heller)
> Terrific. This was at the time their silicon was at revision D > or E, mind you. A friend of mine in the US had friends who used > the part and sent me some (the part is not easy to replace in this > design to this day, their tech support engineer said I would > have no chance to make it work... OK, he did not know me so > he can't be blamed). ( http://tgi-sci.com/tgi/hstb.htm ) > > With Freescale, it has been easier for me to get in touch > with some guy either involved with the design of the part I use > or someone who knows someone etc.; getting data under NDA > has also worked. > But going through the direct channels will be no better than > TI, I am pretty sure. > > Generally I have learned to make my choices based on > technical and price reasoning (the latter has rarely been > important, I don't design many mass-consumer products) and > part survival expectations/gut feeling; one way or the other > one can get the needed data - even from a place like Bulgaria.
I think a problem, nowadays, is that there are *so* many different parts that picking the right horse for longterm availability is easiest done by examining wet tea leaves. I try to design so that I can reuse key aspects of the *design* (not the "particulars") and hope that those things can be easily carried over to a new "platform".
> Perhaps the worst adviser when making a choice can be some > unpleasant experience with sales or support personnel, one > should simply keep being above all the usually related nonsense.
Understood. Though, if they are the gatekeepers, it effectively muddies *all* of your transactions!
FreeRTOS info wrote:
> -jg wrote: >> On Jan 18, 11:19 am, D Yuniskis <not.going.to...@seen.com> wrote: >>> >>> I'm looking at a couple of different parts from Atmel >>> and TI for an upcoming design. I'd appreciate comments >>> (not *rants*) folks might have about both firms in terms >>> of:
>> One simple litmus test, is to look at the Errata sheets, and also >> confirm the target device is actually in real production. > > You say look at the errata sheets, but don't say why. > > Is a small errata the sign of a quality product, or a dishonest vendor. > Or simply that the part is too new for the bugs to have surfaced? > > Is a long errata the sign of a bad product, or an honest helpful vendor > that is trying to prevent you wasting time on known bugs? > > I think you have to know the company well *before* you can come to > conclusions simply by looking at the errata.
Agreed. In the late 70's, I can recall having problems with some Intel parts. Each call to the manufacturer resulted in a fuzzy denial of any problems with the silicon. You were left with the distinct impression that they were chuckling and thinking you obviously didn't know what you were doing... "be kind to him", etc. Eventually, we found a smoking gun. Documented exactly how to reproduce the problem. When confronted, they replied, "Oh, sure. That's ________". I.e., they had known all along of the problem and were probably hoping they would have a fix or workaround before it jeopardized *this* sale -- as well as other sales to us and other folks who were just adopting MPU's at the time. This left a distinct sour taste in my mouth. OTOH, when I was evalating the 32032 for a design, the NatSemi rep handed me the errata lists for the silicon, development tools, etc. in the first batch of documentation provided. Not to say that NatSemi (or the '032) was "better" than Intel, but their *frankness* won them a disprportionate amount of good will! Too bad NatSemi has such an abysmal record with processors. :< I'm a big boy. I *expect* their to be problems with your parts. I can live with that. *If* I know about them and can plan for them (double fault on 68000?). But, if you try to hide them -- or, worse, aren't even documenting them -- then Ii have no way to estimate my risk exposure.
On Jan 18, 1:21 pm, D Yuniskis <not.going.to...@seen.com> wrote:
> rickman wrote: > > On Jan 17, 5:19 pm, D Yuniskis <not.going.to...@seen.com> wrote: > >> Hi, > > >> - quality of their products > > > That is a pretty poorly defined metric. It reminds me of the Volvo > > It is poorly defined only in the sense of how it is *measured*. > But, you *know* a quality product when you see it. You also know > *crap* when you see that!
You can "know" what you will, but if you can't tell me how you measure the thing, it means nothing to me. Likewise, if I tell you a part or a company is "crap" that should mean nothing to you unless I tell you why/how I decided it was "crap". So unless you tell me what "quality" means to you, I can't tell you which companies have it.
> > But then quality is not a measurable thing. Can > > Sure it is! Perhaps not in some "internationally acceptable > interchangeable unit of measurement".
Ok, I'll bite. How do I measure the quality of a CPU chip or a CPU maker?
> E.g., I spent a few summers working for a (huge) hand tool manufacturer. > Part of my job was quality related. Judging the quality of their > current products and how they compare to other manufacturers of > hand tools.
And did you rate them on a scale of 1 to 10 without any sort of a guide from your company? Or did you write about the things that you decided made up "quality"? If neither, then what was the point of your subjective evaluation?
> Tell me, how do you *measure* the quality of a hammer? A screwdriver? > A tape rule? A saw??
Didn't I say that "quality" was not measurable... yes, I think that is what I said.
> First, you verify it meets all of your mechanical specifications. > E.g., what is the draft angle of the two faces of the (slotted) > screwdriver's tip? If it is a "cabinet tip" screwdriver, are the > *sides* of the tip parallel? Are the flutes in a Phillips > screwdriver free of buildup from the plating process? Are the > markings on a tape rule legible and accurate?
Ok, now you are evaluating it to your specs. Is that quality? What if someone else has different specs? Does the quality change?
> Second, you verify that it meets the other design specifications. > E.g., what is the (Rockwell) hardness of the shank? How thick > is the plating?
Ok, more specs...
> Third, you verify that it meets the appropriate "bogo-units". > E.g., if the shank is held fast, how much torque is required > to "strip" the handle off of the shaft? If the screwdriver > tip is pushed into a precision die with a force of X, how much > torque is required to *sheer* the tip off? How many times > can you "bang" a hammer before the handle fails?
Again, more specs...
> Of course, the third group are, by far, the most fun to devise > and implement. They are somewhat arbitrary. Bogus. Yet, > they each pertain to QUALITY FACTORS that the USER WILL PERCEIVE. > > Ever been pissed off because you *tore* the tip off a Phillips > screwdriver? (the average man can do this *easily* for a #0 > screwdriver, "with some effort" for a #1, and "only if really > determined to do so oand with the assistance of leverage > enhanceers" for a #2. #3 requires hydraulic assistance. :> )
That is interesting. So there is a tradeoff between strength of the tip and how well the screwdriver fits your screw. So which has higher quality?
> Notice how *long* the finish on a tape rule lasts? Despite
... snip ...
> unit happens to be) > > > you tell me what you mean by quality? Can you define it in some terms > > that someone else could respond in a way that would have meaning to > > you? > > Sure, obvious things: > - parts failing to meet their published specification (you would > agree that this would be "crap"?) > - parts that *technically* meet their published specification > but not "in good faith". Especially nowadays with datasheets full > of "typ" numbers. ("Yes, typically Icc is 10mA. The fact that > *all* of the devices you have purchased from us draw 100mA is > still within the (unspecified) maximum that we publish for that > part.") > But, also, remember that their "product" isn't limited to bits > of plastic made in the far east: > - documentation that is grossly and obviously incorrect > - errata that are not kept current and/or are "hidden" for > fear that someone would "think ill" of their product
If this is what you wanted to know, why didn't you ask this? By saying "quality" you conveyed none of this to me.
> I was reviewing an SiLabs part last week. Application data in
... snip much ranting ...
> of their silicon? their support? etc. > > >> - accuracy of their documentation > > > My experience is that both Atmel and TI have quality documentation. > > TI seems to be less willing to modify their documentation if you have > > questions it does not answer. Once I got Atmel to add some info to > > their SAM7 data sheets to define crystal requirements. But then they > > provided a table with data points at specific frequencies that didn't > > say what to do in between. I pointed out the issue and they wouldn't > > even comment verbally much less clean up the issue. So I still think > > they are about equal. > > It seems that manufacturers are moving more into just becoming > foundries -- or IP houses (ARM). Trying to get a mix between them > seems to be difficult.
How does this impact you? If it has not changed, Xilinx and Altera are both still pure IP houses using the big fab houses as their only/ primary source of silicon. Other companies, like TI and Atmel run their own foundries while also designing their own chips. I have never had a problem with either. What is it that you are saying about it?
> >> - ability to meet commitments > > > I like this one. What sort of commitments are you talking about? > > Wanna buy a Z380? :>
This also means nothing to me. I am asking you to tell me what you mean by "commitments". There are any number of types of commitments makers make, both implied and explicit. None hold to them all.
> > Production? Updates? Support? If you are a small player, don't > > expect too many commitments in the first place, much less holding to > > them. All IC makers have a handful of major customers for whom the > > sun rises and sets. Everyone else in secondary or even tertiary. > > Of course! I've bought components "by the pound". And, > size shouldn't affect their *ability* to meet their commitments. > When I'm buying 1M of a particular device / year, I have a different > level of expectation (tell me I have to wait 3 years and I'll smile > and turn a new crank on thedesign so your name isn't on any of > the components). When I'm buying 1K of that same device / year, > I *don't* expect the same *timeliness* of a commitment -- *but*, > if you tell me 18 weeks, then I expect it to *be* 18 weeks and > not 24 weeks or 36 weeks or "gee, your request must have got > lost in the cracks"!
Well you are living in a fantasy world. It has been more than once that I was quoted (not promised) parts and they failed to arrive because a bigger fish ate them. The disti said "sorry" and did I still want to keep the PO open for delivery in another month. It happens because if there is a hiccup, they will piss you off rather than the big guy. What would you do, piss of your new, very small customer, or your old, established customer that is 30% of your annual business? ... snip ...
> Thanks for your comments! > --don
Rick