Cross Reference - Universal transistor reference - Page 1
Forum section: electronics / general

author: Brightronics.com
author_rank: Newbie
timestamp: August 25, 2011, 08:33:33 pm
content: Has anyone had any luck finding any cross reference tables or search engines where one can look up any transistor and get a list of all the transistors with compatible specificatoins?It would be nice if there was some way to reverse the NTE cross reference to display all that crosses to the NTE part.

author: vk6zgo
author_rank: Super Contributor
timestamp: August 26, 2011, 02:35:01 am
content: Good luck finding anything that will do that!(though it must be out there somewhere)Many times the equivalents shown in the various books are harder to find than the original component.At one of my earlier jobs,we had semiconductor equivalents book from several sources.Not only did they often disagree,but by the time you had tracked from one book to another,the specs on the final one you turned up were many times quite different to the original.If you can't find a listed equivalent,one good philosophy is to look at the circuit the device is used in.If it is something simple,like a lamp,LED,or relay driver,you can probably replace it with a more common type without any drama.In more complex circuits,have a look at what devices other manufacturers use in similar circuits--there may be a common device which will do the job.Modern devices as a rule,are better spec'd than older ones,so a common modern type may replace an old special type.Substitution of RF power devices needs to be approached with a great deal of caution,& preferably with a Spectrum Analyser on hand.VK6ZGO

author: Unknown
author_rank: Unknown
timestamp: August 26, 2011, 09:57:10 pm
content: Cross-references are not magic, understanding of the circuit and a parametric search of the important parameters is much more reliable. So called equivalent parts, or NTE replacements, may not work at all in some cases, because they were worse in some spec, or the circuit was designed with the assumptions that the part had a fairly low bandwidth.A reverse search for NTE parts wouldn't be that useful, that you can replace both transistor A and B with NTE part X doesn't mean that you can substitute part A for part B. eg. if part A has Ic=3A, Vceo=50V, part B Ic=5A, VCeo=30V, part X with Ic=5A, Vceo=50V might be a substitute for both, but replacing A by B or the other way around may result in fireworks.

author: Fraser
author_rank: Super Contributor
timestamp: August 26, 2011, 10:51:37 pm
content: In the UK when I worked as a 'Saturday lad' in an electronics shop, I used the 'Towers Transistor selector' book. I still have my copy from the 1980's and it still serves me well. It lists the transistors specifications and any equivalent (but not all) You can flick through various ranges of transistors and select a suitably specified part.The internet has changed searching for equivalents but I often find the Towers book faster as I grew up with it and know many favourite equivalent transistors. SMD stuff is too modern for it though so I then have to fall back to internet searches.One thing I did learn all those years ago, was to read the schematic and decide how critical the components specifications were to correct operation. This is crucial for good equivalent selection. Some circuits just will not behave without a very close equivalent part.UPDATE.....I just took a look on Amazon.....the Tower's International Transistor Selector is still availableThe latest revision seems to be December 2008 and it includes SMT transistors. For GBP12, it's a bargain so I have placed an order. I also bought the Tower's FET selector as wellThe internet is great, but I still like to browse through specifications in a book now and then.

author: Brightronics.com
author_rank: Newbie
timestamp: August 28, 2011, 09:27:37 pm
content: Good replies all. Keep it coming!I will look into that Towers book as well. I remember back in the 80's also having a couple books like that exactly. No idea where they got to over the years. I will probably place an order just the same.Since I repair a lot of older analogue audio equipment the transistors only need to be relatively close spec'd for the job in most applications and I usually like to have MCP's. Problem I am running into anymore is getting one with the other. I even have hard time finding just MP's as often it's either the NPN is available or the PNP as one or the other has been discontinued and not available anymore.

author: Brightronics.com
author_rank: Newbie
timestamp: September 08, 2011, 03:59:14 am
content: I did run into a cross reference site!http://www.alltransistors.com/At least its good enough to find similar transistors based on specifications.Have to add.. The site seems to be very comprehensive with information on case types, manufacturers, more than 50,000 transistors referenced. Looks good so far...Can anyone else comment on this site?

author: elementip
author_rank: Newbie
timestamp: October 26, 2011, 02:44:18 pm
content: Quote from: Brightronics.com on August 25, 2011, 08:33:33 pmI managed to reverse the NTE cross reference and put it on the website for the company I work for (an electronic parts retailer). We are an NTE distributer, but NTE would not help us out with this information. We had to find a way to get it on our own.It's made finding the correct replacement part so much easier for our customers - They don't need to cross-ref their part to an NTE part anymore. I'd rather not post the URL here to avoid shameless self-promotion, but feel free to message me if you would like the link.

author: goodhunting
author_rank: Newbie
timestamp: January 18, 2014, 07:22:27 am
content: could i get the link for nte reverse page? thanks

author: codeboy2k
author_rank: Super Contributor
timestamp: January 18, 2014, 12:54:59 pm
content: Quote from: Brightronics.com on September 08, 2011, 03:59:14 amThe site seems to have a lot there, but it needs a face lift with useability in mind..it's hard to read, gray text on black (thank goodness for greasemonkey scripts!) and doesn't present the data in a useful way that I might copy it out into a spreadsheet for further massaging. But it does seem to have the database of transistors and their parameters.There should be a transistor captchashow a part and have the person identify it and enter the data into the database for public use..