While looking for information explaining the IP67 and IP68 specification I came across this interesting new Mosfet.

[Anonymous]

It seemed like it might be a good alternative to the IRF740 which most seem lean toward. Here is a link to the Tech Info on it.
http://www.angliac.co.uk/extras/articles_mdmesh.asp
HH
Beachcomber
PS Does anyone know where I can find an explanation of the IP67 and IP67 ratings? Thanks

 

[Anonymous]

Beachcomber,
You are right, there are new breeds of MOSFETs out there!
Look at the following link for a new MOSFET (STD2NC45-1, Vdss 450V; Rds 4.5 Ohm; Id 1.5A; Pw 30W) with only 27.5 pf output capacitance. It only has a 4.5 ohm on resistance but that is OK for those using a higher resistance or low power coil. The reduced output capacitance should allow you to tweak the damping resistor to a slightly higher value and sqeeeze a little more sensitivity out of the front end. This reduced capacitance also might help squeeze another uS or two out of the overall coil response.
http://www.st.com/stonline/books/pdf/docs/9103.pdf
This might help the folks who are looking to experiment with some faster MOSFETS. I may even try this in the Hammerhead project.
Mouser Elecronics has them in stock.
bbsailor

 

[Anonymous]

Thanks...I'll check it out. Hey do you by any chance know where I can find out what the IP67 and IP68 Standards are? I having a heck of time with it. I can find thousands of items that say they are either IP 67 Certified or IP 68 Certified. But it means nothing if you don't know what the IP67,68 standards represent.
Thanks
HH
Beachcomber

 

[Anonymous]

Beachcomber,
I think this is what you are looking for.
"Using Ingress Protection (IP) Ratings
to help select proper equipment for your application
For load cell sealing techniques, Rice Lake Weighing Systems uses the Ingress Protection (IP) rating system. We find the IP numbers and their definitions are suitable for a classification of load cells and only apply IP numbers to such cells. The IP numbers on a load cell further specify the treatment a specific cell can endure in environments more severe than simple washdown. The following table defines the IP numbers.
Example: Protection level offered by an IP 67 rated protected product
6 = Totally protected from dust
7 = Protected from the effects of immersion between 15cm and 1m
Protection against solid objects
First Number
0 No protection
1 Protected from solid foreign objects of 50 mm and greater (e.g., accidental touch by hands)
2 Protected from solid objects of 12 mm and greater (e.g., fingers)
3 Protected from solid objects more than 2.5 mm (e.g., tools and small wires)
4 Protected from solid objects more than 1 mm (e.g., small wires)
5 Protected from dust; limited entrance (no harmful deposit)
6 Totally protected from dust
Protection against liquids
Second Number
0 No protection
1 Protected from vertically-falling drops of water (e.g., condensation)
2 Protected from direct sprays of water up to 15

 

[Anonymous]

[No message]