pic temperature ranges relative to packages - Page 1
Forum section: electronics / general

author: Simon
author_rank: Unknown
timestamp: October 11, 2011, 12:07:20 pm
content: I'm doing a design based around a PIC. It must have the -40 to 125 C range but from looking at farnell only certain packages have this range, typically DIP or the square soic thingys, but why not standard soic packages ? is it farnell that won't stock them or uchip that don't make them ?

author: GrumpyDave
author_rank: Contributor
timestamp: October 11, 2011, 02:02:38 pm
content: You can get the high temp range of PIC (+125 deg) in a SOIC package it just needs the "Extended" package prefixe.g. PIC18F25K22-E/SOStandard temp i.e. +85 deg would be "Industrial" with I package prefix = PIC18F25K22-I/SOObviously I do not know what pic you require this is just an example, I only looked on RS but it may be that you will need to change which PIC to use in your project if you can only buy from the usual component suppliers.Hope that helps..

author: Simon
author_rank: Unknown
timestamp: October 11, 2011, 02:26:21 pm
content: well that is my worry, I design around a pic only to find that no one supplies it in the -40/125 range, according to uchip all pics are available in this range, I think I'm safe with the 16F88 even if i end up using the quad package. I could no even use the RS website, I don't know what they think they are doing but i'm not using them again until they put the parametric search back

author: GrumpyDave
author_rank: Contributor
timestamp: October 11, 2011, 02:41:27 pm
content: Hmm well farnell do sell the extended package 16f88 but its US stock only which is a little annoying for us euros..http://uk.farnell.com/microchip/pic16f88-e-so/ic-8bit-mcu-pic16f-20mhz-soic-18/dp/1847793or mouser is cheaper:http://uk.mouser.com/ProductDetail/Microchip-Technology/PIC16F88-E-SO/?qs=sGAEpiMZZMsUzhEcHltCuV3X%2fOtOy8mY

author: baljemmett
author_rank: Unknown
timestamp: October 11, 2011, 03:08:41 pm
content: Alternatively MicrochipDIRECT have it cheaper in four packages:http://www.microchipdirect.com/ProductDetails.aspx?Category=PIC16F88&Sort=TempRange&TempRange=-40C+to+%2b125C(I see they'll also program the parts for a few pence per chip plus a < 20 quid setup fee -- might be useful if you're going to be doing any volume!)

author: Simon
author_rank: Unknown
timestamp: October 11, 2011, 05:00:09 pm
content: no i won't be doing that many and will be happy to program myself, so looks like chips are available I just need to look around

author: ChrisKiwi
author_rank: Contributor
timestamp: October 12, 2011, 02:19:07 am
content: Quote from: Simon on October 11, 2011, 05:00:09 pmYou can buy small quantities from MicrochipDirect but I guess small quantity could mean different things to different people, in the same way as "not that many" could also. The cost of the shipping may not be that bad, very much depends where they are being shipped from relative to where you are.

author: Simon
author_rank: Unknown
timestamp: October 12, 2011, 05:31:09 am
content: microchip themselves are extortionate, I haven't forgotten a pickit that was on sale fore £ 17.50 and ended up at £35.00 before I hit the send button due to all of the charges

author: baljemmett
author_rank: Unknown
timestamp: October 12, 2011, 11:36:59 am
content: Quote from: Simon on October 12, 2011, 05:31:09 amWell, to take the PIC16F88-E/SO as an example, their price is half that of Farnell -- and after some digging it looks like a £10 shipping fee vs. Farnell's £15 US-stock surcharge. Mouser's prices fall between the two on both counts (although free shipping for bigger orders) -- so it looks like you pays your money and your takes your choice -- getting full prices first seems like a wise plan!(A doubling in price sounds a bit on the unpleasant side, though, I'd agree! I'm guessing something like £10 delivery and then VAT on top of the total? Both of those could come into play with other vendors, alas, depending on order size.)

author: Simon
author_rank: Unknown
timestamp: October 12, 2011, 11:44:44 am
content: it was vat, a packing fee and postage it was stupid, ryan air style pricingthey are not that cheap for the 16F88 e/so, it's like £3.60 (+ vat i bet) even if i buy 100, farnell don't list them at all

author: metalphreak
author_rank: Frequent Contributor
timestamp: October 12, 2011, 11:49:08 am
content: I've found microchip direct to be pretty competitive to other alternatives in Australia. The shipping has always been a flat fee of about $17 per order so it's certainly not economical for small or single unit orders. In times of desperate need, I've bought PIC devices from RS-Components, paid $20/chip for the privilege but received them overnight. Getting around 50 of them for a production run worked out to less than $5/chip (from MCD).Don't forget, you can put the part number into the "findchips" banner at the topFind out who sells the one you need besides MCD.

author: Simon
author_rank: Unknown
timestamp: October 12, 2011, 11:52:31 am
content: well i won't need the mil spec temp range for a bit so can hunt around and compare, it was more essential to know that they exist and in what packages so that I can get my board layout sorted. I could put the part number into the findchips bar if the damn thing even worked (chrome) I have never seen this elusive bar ever on this forum. But yes i could go and find their service and use it

author: baljemmett
author_rank: Unknown
timestamp: October 12, 2011, 12:48:13 pm
content: Quote from: Simon on October 12, 2011, 11:44:44 amHmm, I'm a bit puzzled by that! I see £2.33 at Microchip, and Farnell do list them for £5.51 (see GrumpyDave's link, although I get the same thing just sticking "16F88-E/SO" in the search box.) The happy fun joy overheads are going to be the £16 surcharge for US stock from Farnell, vs. shipping for Microchip whichappears to be £10 give or take a few brass washersdepending on weight. And yes, I'd expect both are going to be ex-VAT prices, so add 20% for that unless you can claim it back.But anyway, as you say, it's enough to know that youcancan them at this stage -- getting bogged down in the logistics might be a little premature

author: Simon
author_rank: Unknown
timestamp: October 12, 2011, 01:03:35 pm
content: http://www.microchipdirect.com/ProductDetails.aspx?Category=PIC16F88&Sort=TempRange&PackageType=SOIC&TempRange=-40C+to+%2b125CI can't even find them on farnell

author: baljemmett
author_rank: Unknown
timestamp: October 12, 2011, 01:10:54 pm
content: Quote from: Simon on October 12, 2011, 01:03:35 pmThat comes up with £2.33 for me, weird. Just a thought -- you aren't being shown the USD prices, are you? There's a 'change location' link at top left to switch to GBP if so!

author: Simon
author_rank: Unknown
timestamp: October 12, 2011, 01:33:10 pm
content: ah yes I was getting it in dollars, well spotted, I thought the website was able to set location automatically. well no brainer then