Post by thread:[EE] Maxim MAX7300 I2C port expander

Hello Everyone, I'm looking for the MAX7300 port expander but it seems that none of my usual suspects (Digikey, mouser, allied, future, newark) have any. I've been quoted a 40 day lead time for a few samples. The part is in use by Chevy and Ford, so I assume there are plenty manufactured. I've heard, though, that the auto industry has the ability to use up an entire production quantity of some parts. Right now I just need a couple samples (44pin QFN) but before long we'll need 30,000 and would rather not commit to this part if its too hard to come by. Does anyone know of any other avenues to look down? Thanks all! James

I don't know you requirements other than expand ports via i2c, so this may not be exactly what you need, but Microchip makes a few of those. Both the MCP23016/17 are 16 bit i/o port expanders, the 16 vcc is 2.0 to 5.5 and the 17 vcc is 1.8 to 5.5, also, the 16 has a max bus frequency of 400kbits/sec while the 17 is 1700 kbits/sec. The budgetary price is $1.15 for the 16 and $0.86 for the 17. Good luck. -Mario {Quote hidden}> Hello Everyone, > > I'm looking for the MAX7300 port expander but it seems that none of > my > usual suspects (Digikey, mouser, allied, future, newark) have any. I've > been quoted a 40 day lead time for a few samples. > > The part is in use by Chevy and Ford, so I assume there are plenty > manufactured. I've heard, though, that the auto industry has the ability > to > use up an entire production quantity of some parts. > > Right now I just need a couple samples (44pin QFN) but before long > we'll > need 30,000 and would rather not commit to this part if its too hard to > come > by. Does anyone know of any other avenues to look down? > > Thanks all! > > James > -

Thanks Mario, The only problem with those is that we need 28 IO ports. It would be easy enough (for me, the software guy) to just use two of them but now the board is layed out and there would be resistane to changing it if we could just find the right part somewhere. It may be that we end up having to use these parts and just redo the board. I saw on the CCS compiler site example code for the MAX7300. Thats another thing that would make me think it would be more available, but alas... still looking. James

> -----Original Message----- > From: spam_OUTpiclist-bouncesTakeThisOuTmit.edu On Behalf Of James Humes > Sent: Thursday, December 08, 2005 12:21 PM > > I'm looking for the MAX7300 port expander but it seems that > none of my > usual suspects (Digikey, mouser, allied, future, newark) have any. I've > been quoted a 40 day lead time for a few samples. Check the availability at their e-commerce site: https://shop.maxim-ic.com (no registration needed for price and availability checks) Using MAX7300 it shows that quite a few of the variants are in stock for <100 piece quantities. Also there are free samples in stock for a number of the variants. Paul

> > > Check the availability at their e-commerce site: > https://shop.maxim-ic.com > (no registration needed for price and availability checks) > > Using MAX7300 it shows that quite a few of the variants are in stock for > <100 piece quantities. Also there are free samples in stock for a number > of > the variants. > > Paul Hi Paul, The issue is that I need the QFN package (MAX7300AGL) and there is a 6 week lead time on it from Maxim. We're putting together a few prototypes in an RF application or else I would just use a different package and try to make it work. I was hoping to find a supplier with a stock of them. James

> The only problem with those is that we need 28 IO ports. It would be > easy enough (for me, the software guy) to just use two of them but now the > board is layed out and there would be resistane to changing it if we could > just find the right part somewhere. It may be that we end up having to use > these parts and just redo the board. They put a part in the PCB layout without checking availability first? Shame, shame. Maybe this should just be a lesson to them to do more homework before selecting a component. And, incidentally, why are you (the software guy) doing the legwork on a piece of hardware? Mike H.

Mike Hord wrote: > They put a part in the PCB layout without checking availability first? > Shame, shame. And considering it's a Maxxim part, they should have assumed availability problems, whether it happens to be in stock at that time or not. ****************************************************************** Embed Inc, Littleton Massachusetts, (978) 742-9014. #1 PIC consultant in 2004 program year. http://www.embedinc.com/products

> > > They put a part in the PCB layout without checking availability > first? Shame, > shame. > > Maybe this should just be a lesson to them to do more homework before > selecting a component. And, incidentally, why are you (the software guy) > doing the legwork on a piece of hardware? > > Mike H. Hi Mike, Its a small company (3 people total) so we have to fill different roles at different times. My boss does the electronic design and layout so it is hard (or rather, not my place) to distribute shame for this kind of thing:) Its not life or death since we're just prototyping. The personal issue (that you may be able to see) is that I'd rather not tell my boss to lay the board out again if at all possible, especially since the part is available just with a long lead time. But, on the other hand, we do need to get these prototypes going. James

> Its a small company (3 people total) so we have to fill different roles > at different times. My boss does the electronic design and layout so it is > hard (or rather, not my place) to distribute shame for this kind of thing:) > Its not life or death since we're just prototyping. The personal > issue (that you may be able to see) is that I'd rather not tell my boss to > lay the board out again if at all possible, especially since the part is > available just with a long lead time. But, on the other hand, we do need to > get these prototypes going. This is exactly the time for him to learn this lesson. Of course, "shame" may not be the way to go about it, but if you can't find it (or a pin compatible drop-in), shame or not, you're up a creek. And if he carries on designing things with no eye towards actually being able to produce them, that creek will be very wide and very deep. If you're going to make 30,000 of these, you may even need to be thinking beyond availability to "what's available in China" (or wherever you're having these 30,000 units assembled). FWIW, I do some work in a 3-person outfit, doing hardware and firmware, and I learned that lesson the hard way as well. I had several "perfect" components, and then learned to my chagrin that they were unavailable. I didn't actually get to the point of having PCBs made with the wrong component footprint, but I did do a layout that I had to change. Sidebar- does TI make a replacement? They seem to make a fair number of clone parts, and sometimes have better availability than Maxim. Mike H.

James Humes wrote: >Hello Everyone, > > I'm looking for the MAX7300 port expander but it seems that none of my >usual suspects (Digikey, mouser, allied, future, newark) have any. I've >been quoted a 40 day lead time for a few samples. > > The part is in use by Chevy and Ford, so I assume there are plenty >manufactured. I've heard, though, that the auto industry has the ability to >use up an entire production quantity of some parts. > > Right now I just need a couple samples (44pin QFN) but before long we'll >need 30,000 and would rather not commit to this part if its too hard to come >by. Does anyone know of any other avenues to look down? > >Thanks all! > >James > > This has happened so many times with Maxim that most designers have given up. Add also a high cost, and you have a recipe for disaster. Don't design these guys in. They are flimflam artists. --Bob -- Note: To protect our network, attachments must be sent to .....attachKILLspam@spam@engineer.cotse.net . 1-520-777-7606 USA/Canada http://beam.to/azengineer

> -----Original Message----- > From: piclist-bouncesKILLspammit.edu > Sent: Friday, December 09, 2005 9:07 AM > > This has happened so many times with Maxim that most > designers have given up. Add also a high cost, and > you have a recipe for disaster. > > Don't design these guys in. They are flimflam artists. > > --Bob I just do not know why they are still doing so well since lots of the people advise not to design Maxim parts in. Maybe all the leading analog IC vendors like Analog Device and Linear Tech and Maxim all have similar problems. Still it is hard to avoid them in some designs. Last time I was designing a level sensor (cost is almost not an issue there since the major cost is not the electronics and the margin is very high) I still use a Maxim part (MAX4634EUB) due to its better performance and small packaging. That is why company Now I am in a different situation where cost is the most important factor and I will try to avoid any expensive parts and parts with potential delivery problems (like an AVR MCUs and Maxim parts). Regards, Xiaofan

> Sounds like it is time to lean on Maxim "what do you mean we cannot get > them, we design them in, and now you say you don't have them?" Answer: You want 100? <muffled>Hey Frank, I've got this guy on line 2 that wants 100!</muffled> <pause until everyone gets done lauging> We won't have stock for about 16 weeks. I'm really sorry sir, there is nothing I can do. Try some of our distributors. Honest answer: If we really cared whether gnats like you bought 100 parts we'd have them in stock, wouldn't we? Duh! I've got to get back to a real customer that needs 500000 of these parts next week. Click. ****************************************************************** Embed Inc, Littleton Massachusetts, (978) 742-9014. #1 PIC consultant in 2004 program year. http://www.embedinc.com/products

On Fri, 9 Dec 2005 07:42:30 -0500, you wrote: >> Sounds like it is time to lean on Maxim "what do you mean we cannot get >> them, we design them in, and now you say you don't have them?" > >Answer: You want 100? <muffled>Hey Frank, I've got this guy on line 2 that >wants 100!</muffled> <pause until everyone gets done lauging> We won't >have stock for about 16 weeks. I'm really sorry sir, there is nothing I can >do. Try some of our distributors. > >Honest answer: If we really cared whether gnats like you bought 100 parts >we'd have them in stock, wouldn't we? Duh! I've got to get back to a real >customer that needs 500000 of these parts next week. Click. > Sounds like typical Maxim..... easy samples but you're stuffed for production. Maxim is close to the bottom of the list of suppliers I consider designing in as they've always been like this. I think a significant reason for Microchip's success is that they have a stated policy , and track record, of very good availability & short (typically zero) leadtimes for any quantities - streets ahead of most of the competition.

Olin Lathrop wrote: {Quote hidden}>> Sounds like it is time to lean on Maxim "what do you mean we cannot get >> them, we design them in, and now you say you don't have them?" > > > Answer: You want 100? <muffled>Hey Frank, I've got this guy on line 2 > that > wants 100!</muffled> <pause until everyone gets done lauging> We won't > have stock for about 16 weeks. I'm really sorry sir, there is nothing > I can > do. Try some of our distributors. > > Honest answer: If we really cared whether gnats like you bought 100 parts > we'd have them in stock, wouldn't we? Duh! I've got to get back to a > real > customer that needs 500000 of these parts next week. Click. > > > ****************************************************************** > Embed Inc, Littleton Massachusetts, (978) 742-9014. #1 PIC > consultant in 2004 program year. http://www.embedinc.com/products Olin: nobody could have explained it better. Have a great day. --Bob -- Note: To protect our network, attachments must be sent to .....attachKILLspam.....engineer.cotse.net . 1-520-777-7606 USA/Canada http://beam.to/azengineer

Thanks for all the feedback on this. I think I detected hints of sarcasm here and there but being as I don't have the emotional capacity to detect this sort of thing I couldn't really say. <g> Solution: Relayout the board to use microchip's io expanders and check availability more carefully in the future. A slight aside: I know of someone who had a product designed around a TI part that had been in production for several years when TI obseleted (obselesced?) the part. Apparently 4 or 5 different medium volume customers complained and TI decided to keep the part alive out of kindness and good customer service. I'm working on a 30K units a year product now, but I just graduated and this is my first real job... A few years from now who knows.. I may be working on higher volume product in a role where I'm choosing the parts to design around and my experiences now (both technical and customer service related) will be formative (subconciously and conciously) in which parts I choose later. However, I don't mean to sound disgruntled because I'm actually relatively gruntled. Thanks everyone, James

well.....I never design in a maxim part. Period. Even if it costs a little bit more to use two parts, or from a different vendor.....its well worth the frustration of NOT being able to get parts during production. Been burned a few times....learned... We use the microchip part and it has a nice feature of latching the inputs so if you get an irq that something changed...you can go read it at your leisure and then clear it. nice feature I think! --------------------------------- Yahoo! Shopping Find Great Deals on Holiday Gifts at Yahoo! Shopping

Also, the microchip port expanders are cheaper for two than a single of these other parts. James On 12/9/05, alan smith <EraseMEmicro_eng2spam_OUTTakeThisOuTyahoo.com> wrote: {Quote hidden}> > well.....I never design in a maxim part. Period. Even if it costs a > little bit more to use two parts, or from a different vendor.....its well > worth the frustration of NOT being able to get parts during > production. Been burned a few times....learned... > > We use the microchip part and it has a nice feature of latching the inputs > so if you get an irq that something changed...you can go read it at your > leisure and then clear it. > > nice feature I think! > > > --------------------------------- > Yahoo! Shopping > Find Great Deals on Holiday Gifts at Yahoo! Shopping >

On Dec 9, 2005, at 3:32 PM, alan smith wrote: > .I never design in a maxim part. Period. Even after they acquired Dallas? Dallas had/has some nice parts, and they never had quite the "unobtainium" reputation of the Maxim parts. Has that gotten worse since the merger? I was always a bit surprised that Maxim bought Dallas rather than the other way around... BillW