Is Rochester legit? - Page 1
Forum section: electronics / projects

author: VEGETA
author_rank: Super Contributor
timestamp: November 02, 2022, 05:21:59 pm
content: Hello,I have found that Rochester is selling many chips on a very low price compared to Digikey and Mouser. They don't seem Chinese cloning sites, and they put original manufacturer correctly.Some examples (@100 quantity):AD725 -> Digikey about 11$, while Rochester about 4.5$.LMH1980 -> Digikey 4.8$, Rochester 2.7$.EL5462 -> Digikey about 4.3$, Rochester 3.4$.these are significant reductions which makes total budget of a production run a lot cheaper.Are these guaranteed original chips? and why they are so cheap?Any real designer here used Rochester chips in real products?thanks

author: Benta
author_rank: Super Contributor
timestamp: November 02, 2022, 06:25:53 pm
content: Rochester is absolutely legit, but a very special distributor.They supply obsolete parts that no one else have (hence the prices).Rochester has contracts with all the major manufacturers for "last-time-buys" to keep the parts in stock after end of production.This also implies: do not use such parts for new designs! It's purely for maintenance.

author: wraper
author_rank: Unknown
timestamp: November 02, 2022, 06:37:47 pm
content: Digikey itself has no stock of AD725. All AD725 available on Digikey are marketplace items from Rochester. When buying from Rochester you should expect parts with old date codes. Therefore they may be old parts with lead contained in them. So check part number suffixes if it matters.

author: jmelson
author_rank: Super Contributor
timestamp: November 02, 2022, 06:37:57 pm
content: I bought a bunch of power FETs from them at a VERY good price some months ago, when the usual dists had none. I had to buy a lot of 200 pieces, though. When I went back to them, they were all gone! So, they had some lot of parts parts from the end of a production run, and sold out. Now Digi-Key and other dists are back in stock -- makes NO sense! But, they are surely the most legit source for truly obsolete parts.Jon

author: VEGETA
author_rank: Super Contributor
timestamp: November 02, 2022, 06:50:44 pm
content: These parts I listed are not obsolete or last time buy, they are active parts. Digikey marketplace uses Rochester so it maybe a good choice to use it to consolidate shipping rates.I don't mind slightly older parts as long as they are genuine and not used, as advertised.

author: Benta
author_rank: Super Contributor
timestamp: November 02, 2022, 07:20:54 pm
content: Quote from: VEGETA on November 02, 2022, 06:50:44 pmThey may be obsolete if they are in packages with lead or other RoHS materials. Parts in newer packages may be active.

author: free_electron
author_rank: Super Contributor
timestamp: November 02, 2022, 07:21:35 pm
content: rochester not only does last time buys. they actually have a waferfab. they buy the masks and produce more parts using the original masksets.

author: Benta
author_rank: Super Contributor
timestamp: November 02, 2022, 07:26:37 pm
content: Quote from: free_electron on November 02, 2022, 07:21:35 pmVery interesting. Rochester seems to have branched out over the last years.Anyway, yes, Rochester is certainly a legit and serious company.

author: Hydron
author_rank: Super Contributor
timestamp: November 02, 2022, 08:57:54 pm
content: I've been saved by Rochester in the past - got a big order for an old design and they were the only option for a critical part, got good parts at a price that might have even been slightly lower than digikey/mouser etc offered before the part went obsolete.

author: free_electron
author_rank: Super Contributor
timestamp: November 02, 2022, 11:52:03 pm
content: Quote from: Benta on November 02, 2022, 07:26:37 pmthey have been doing that since at least the 90's. i remember buying tms9900 processors from them as far back as 1994...

author: Sceptre
author_rank: Regular Contributor
timestamp: November 03, 2022, 01:26:11 am
content: Quote from: free_electron on November 02, 2022, 07:21:35 pmWhere is this fab?

author: free_electron
author_rank: Super Contributor
timestamp: November 03, 2022, 03:45:25 pm
content: Quote from: Sceptre on November 03, 2022, 01:26:11 amThey use several foundries and have one somewhere int he US for the older technologies. They also have a wafer store and can cut and package dies.

author: coppice
author_rank: Super Contributor
timestamp: November 03, 2022, 04:02:47 pm
content: Quote from: free_electron on November 03, 2022, 03:45:25 pmProducing old chips is usually impractical. Very few devices can be moved from one fab to another, especially older processes, where even the masks were rarely portable from fab to fab. Rochester has a substantial business in long term wafer and die storage. They can dice them, package them, and have the original vendors test programs to run on industry standard test systems to test the devices, just like the original vendor (or more often its subcontractors) did. A major cause of a device being canned by its maker is they are closing the only fab capable of making it at the end of its life. I can imaging Rochester taking entire design information from the original maker for devices made in currently functional foundry processes. I doubt they do any fab work in house.

author: Terry Bites
author_rank: Super Contributor
timestamp: November 06, 2022, 09:39:30 am
content: they'll sue you if you cast doubts again!