Saturday, January 24, 2009

FET Derating Guidelines


Derating guidelines for a 2N7000 Field Effect Transistor [FET] was added; 2N2700 Derating.
Unlike the other pages within the FET Derating section, this page only offers recommendations.
All the other pages, or many of them, provide derating curves that should be considered as absolute rules rather than recommendations.
Of course a FET is a style of Transistor, which are covered on the Transistor Derating Guidelines.

The over-all section is Component Derating, if you see a table than it's a guideline, while a curve will imply a rule. The goal is to not exceed the devices junction temperature.

The 2N27002 FET is also covered on the page link.
The 2N7000 device is a plastic TO-92 package, while the 2N7002 is a SOT23 plastic package.

Of course Connector derating guidelines and Cable derating guidelines are also provided within this section, neither of which have a semiconductor junction. Their package or molding is being derated. A Thermal Couple is used to monitor the body of the package for temperature increases. There's a limit to the number of wires in a cable or pins on a connector that can carry some amount of current. Sure one pin may handle an amp of current, but if the connector or cable has 50 leads, does it imply that the component can deal with 50 amps of heat dissipation [no].

For reference;
2N6770 Maximum Case Temperature.
2N6768 Maximum Case Temperature.
2N6766 Maximum Case Temperature.
2N6764 Maximum Case Temperature.

5 comments:

Leroy said...

1/24/09 I added the How to Derate a FET a few weeks ago, but I just got around to posting some links. There are more pages not addressed in this posting

Leroy said...

1/25/09 Guess it's a good thing I add this posting yesterday because the 12 FET Derating pages are not getting any incoming visits.

Maybe we all know how to derate a FET already.

I just did a Google search for FET Derating and my page showed up first, so I know it's been indexed.

Leroy said...

7-4-09 The section on How to Derate a FET is still not getting any hits, maybe 2 page view a-day. There are 12 pages that make up the section, so most pages don't even get viewed on a daily basis.

Leroy said...

6/1/10 This posting is for the 2N7000 and 2N7002 series of N-Channel Enhancement Mode Field Effect Transistors, while the typo in the posting indicates a 2N2700 part.

Leroy said...

12-9-2010 In the last 2 years the page relating to the 2N27000 has only received 388 page views, that's like a pageview every other day...