Anything bigger than the IRF2807 in the same TO-220AB package? - Page 1
Forum section: electronics / beginners

author: Neato3000
author_rank: Newbie
timestamp: March 12, 2013, 02:37:33 pm
content: The irf2807 is a power mosfet that's advertised to run 75 volts or 82 amps, with an on resistance of 13 milliohms. The max power dissipation is 230 watts. For the price they are wonderful, and are my favorite mosfet. I use them for all my power switching stuff.Is there another mosfet out there that will handle a higher voltage, with at least the same amperage and power dissipation? I can run the fets in parallel to get around the amperage, I just don't think I can do the same in series for the voltage. Even if I could, that would just double the amount of mosfets on my board, and add an extra amount of resistance, where some of my applications need as little as possible.I'm not even pushing these to there fullest yet, simply because I don't have the power yet. But once I do, I'd like to be able to switch 144v dc on a half ohm load. This is my hungriest application, the fet should also be able to run a hefty 12v dc load as well. Can't forget about the $2 price range either. The IRF2807 is around $1 to $1.50 on ebay, and I have found them for 50 cents before.Of course there also may be something to do with my circuity that can help me overcome these power obstacles. Any ideas? Thanks!Chris

author: Neato3000
author_rank: Newbie
timestamp: March 12, 2013, 04:22:59 pm
content: Quote from: AcHmed99 on March 12, 2013, 02:56:36 pmI know right? Ha ha, 12 x 12v volt batteries. Correct me if I'm wrong with any of this, but with a lead acid battery able to push 450 cranking amps, I'm only somewhere over half of that. The load is also a motor, so I'm not constantly pulling that much amperage any way. It's only the initial start up that draws the huge amperage, among loading the motor down. But that's another subject over a why not project, ha ha. I was just wondering if there was such a mosfet.

author: rsjsouza
author_rank: Super Contributor
timestamp: March 12, 2013, 05:38:09 pm
content: A quick glance at a Vishay selection table showed a few possible candidates:SUP85N15-21,SUP57N20-33and so on...

author: Neato3000
author_rank: Newbie
timestamp: March 12, 2013, 06:14:54 pm
content: Quote from: rsjsouza on March 12, 2013, 05:38:09 pmGreat! Thanks a lot! That SUP85N15-21 is pretty much exactly what I'm looking for. I guess though if you double voltage, you double the price. The cheapest I have found with some quick research was $3.75 from Mouser. Most are around $5. Thanks for the help, this is the type of stuff that keeps me a beginner. Sometimes I just don't know where to look.

author: rsjsouza
author_rank: Super Contributor
timestamp: March 12, 2013, 09:29:32 pm
content: Nice to hear this works for you.Just to help you in the future, here's what I did to find this guy: went to the Vishay website, clicked on the MOSFETS link at the top page.Once the MOSFETS page opened, I simply clicked on a suitable voltage range for your requirements (81 to 250V).This link leads to a parametric table, which you can easily filter or sort by a specific parameter - I selected the small icon under IDMAX(A) to select the descending sort order (so it got the higher amps first) and started to look for other parameters of interest: VDS, rDS(ON)and PDMax.As AcHmed99 mentioned, the distributors such as Digi-key, Mouser, etc. also have similar parametric tables, which can also be sorted to find out the parts.Have fun with your switcher!

author: fmaimon
author_rank: Unknown
timestamp: March 12, 2013, 11:09:16 pm
content: If you want to drive a motor with 12 x 12V batteries then you should get a MOSFET rated at least with 250 V, as you will get spikes when switching the motor on and off. It is 1.5 * 12 * 14.4V (max voltage of a lead acid battery), but I would go to at least 350V, just to be safe.

author: ZOMGVTEK
author_rank: Contributor
timestamp: March 12, 2013, 11:58:58 pm
content: The IRFB4110PFB is one of the better TO-220 package MOSFETS. You can find them for about $2 a piece in higher QTY, $3 or so if you only need a few. If you buy it off eBay of from China it's probably a fake. However, it's a 100V FET.Switching 144VDC Peak on a low cost TO-220 MOSFET is a bit tricky. The IRFB4115 is known to be up to the challenge, but you would be running the component towards its absolute upper limit as it has little to no overhead beyond its design spec. The IRFB4110PFB is known to operate fine even in the 110-115V range and is rated to carry a whole lot of power for a TO-220 package. It's rated current is bond wire limited. Depending on how you want to use it, I would think some ultra low ESR snubbers would allow the IRFB4115PBF's to tolerate 144VDC peak operation just fine.If it's not going to the moon and has proper protection, the IRFB4115PBF's will work fine. They're rated at about half the Rds(on) as the sup85n15 and a bit more current.

author: Neato3000
author_rank: Newbie
timestamp: March 13, 2013, 02:46:43 am
content: This place is a treasure! I knew I'd find something here.Quote from: ZOMGVTEK on March 12, 2013, 11:58:58 pmThis is a pretty amazing fet! I'm looking at the datasheets and eBay right now. Apparently there is only one person selling the IRFB4115 for $5, however, there seems to be an abundance of the IRFB4110s. I can get 20 of them for a dollar each. They are all from China, but I really haven't had that much trouble with counterfeit parts. Although, if I have received any I wouldn't know ha ha. Thanks a lot!Quote from: fmaimon on March 12, 2013, 11:09:16 pmThanks for the reply, I think you're right about the kickback. From what I have gathered though, is that the higher voltage a fet can handle, the lower amperage capabilities it has. I may be wrong, but that's why I'm here asking questions, ha ha.Quote from: rsjsouza on March 12, 2013, 09:29:32 pmThanks a lot, I wasn't very sure what a parametric search was, ha ha. Thanks for explaining that! I will definitely keep this in mind.Thanks alot guys!Chris

author: chickenHeadKnob
author_rank: Super Contributor
timestamp: March 13, 2013, 03:44:43 am
content: Quote from: Neato3000 on March 13, 2013, 02:46:43 amI can guarantee from experience those 1 dollar IRFB4110's are counterfeit and do not have the same device parametrics or consistency of the real thing.You want too large of a range to be handled by a single stock part. The lower voltage IRF parts have better RDS on and are to be preferred if you don't need the operating voltage .

author: Neato3000
author_rank: Newbie
timestamp: March 13, 2013, 04:57:12 am
content: Quote from: chickenHeadKnob on March 13, 2013, 03:44:43 amYou're right, if I'm going to build something, might as well use the right stuff. As far as voltage goes, I don't need it now, but I will. If I knew I could run them in series, I might just buy a bunch of low voltage stuff, but that's still not very elegant, ha ha. Thanks for your reply!

author: ZOMGVTEK
author_rank: Contributor
timestamp: March 14, 2013, 01:01:55 am
content: The IRFB4110's on eBay are almost always fakes, and not very good ones at that.$2.45 a piece from moose. Someone on ES might be selling the 4115's if you need a bit more voltage. The 4110's are very good TO-220's.http://endless-sphere.com/forums/viewtopic.php?f=31&t=47636

author: ZOMGVTEK
author_rank: Contributor
timestamp: March 14, 2013, 01:05:33 am
content: Essentially all TO-220 package FET's look alike, but can perform VERY differently. Right now all the ones I see on eBay are fakes. If you run those, you might as well save some money and get some junk 100V FET's that at least have a data sheet to show how horrible they are.http://endless-sphere.com/forums/viewtopic.php?f=2&t=10655If you need the 150V version, someone on ES usually stockpiles a bunch and sells them at a good price.http://endless-sphere.com/forums/viewtopic.php?f=31&t=25601&p=532814&hilit=4115#p532814This is old, but he might still be willing to sell a few since it sounds like you don't need many.

author: Neato3000
author_rank: Newbie
timestamp: March 14, 2013, 03:29:23 am
content: Quote from: ZOMGVTEK on March 14, 2013, 01:01:55 amQuote from: ZOMGVTEK on March 14, 2013, 01:05:33 amThis is great guys, Thanks! I have never heard about ES before. It sounds like the right place to look for some other questions I have as well. And I'll definitely be making sure I buy real deal fets. Thanks again!!