Take a look at these new Field effect rectifiers from ST-Microelectronics. - Page 1
Forum section: electronics / general

author: BrianHG
author_rank: Super Contributor
timestamp: February 16, 2018, 04:44:46 pm
content: Impressive forward voltage drop of only 0.31v at 10 amps and 0.42v at 20 amps.http://www.st.com/content/st_com/en/products/diodes-and-rectifiers/field-effect-rectifiers/ferd40u45c.html

author: jmelson
author_rank: Super Contributor
timestamp: February 16, 2018, 09:20:22 pm
content: 100 mA reverse leakage when hot, 4000 pF at low voltage, and absolutely no AC performance data.Well, I'd like to know more about it....Jon

author: Cyberdragon
author_rank: Super Contributor
timestamp: February 16, 2018, 09:32:44 pm
content: PFFFT! Reverse only 45V!Quote from: jmelson on February 16, 2018, 09:20:22 pmForwardRMScurrent is 40A.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: February 16, 2018, 09:43:01 pm
content: SPICE models all say TT=0 so either they didn't model it (quite possible) or it's more or less schottky-like.One would expect majority carriers, one way or another (schottky and field effect), so they should be fast.No evidence of guard ring behavior (causes reverse recovery behavior in schottky diodes driven to high currents). Again, could be an incomplete model. Forward voltage is only graphed up to 0.6V, no help there.Tim

author: komet
author_rank: Unknown
timestamp: February 16, 2018, 10:28:20 pm
content: Looks like it might make an interesting varicap...

author: TerraHertz
author_rank: Super Contributor
timestamp: February 16, 2018, 10:39:16 pm
content: Nice.My immediate thought was "Oh, I hope they do a bridge rectifier with such low Vf".Something I've wanted for a specific application for a long time.Their 'Diodes and rectifiers selection guide' makes no mention of bridge rectifiers.ST site search for 'bridge rectifier' finds nothing. Seriously, don't they make any? Not sexy enough? So they didn't think to try offering ultra-low-Vf ones either?Sigh.Please no one suggest using three of these to make a bridge.

author: coppice
author_rank: Super Contributor
timestamp: February 17, 2018, 01:30:03 am
content: I presume they have a target market for these things. People rarely put something like this out just to see if customers bite. I wonder what that target market is?

author: hermit
author_rank: Frequent Contributor
timestamp: February 17, 2018, 01:54:08 am
content: Quote from: coppice on February 17, 2018, 01:30:03 amPackaged in TO-220AB, and D2PAK, this device is intended to be used in switch mode power supplies, or automotive applications

author: NiHaoMike
author_rank: Super Contributor
timestamp: February 17, 2018, 04:31:45 am
content: Any technical details of what a "field effect rectifier" really is? Is it a MOSFET and synchronous rectifier controller packaged to be a drop in replacement for a rectifier diode or is it some totally new kind of diode? (I suspect the latter.)TI SM74611 only has about 33mV drop at 10A. But it's only for very low frequency applications. I have one in my solar power setup and given it has less than a tenth the voltage drop of the Schottky it replaced, it's no longer surprising that it gives off no noticeable heat. (It was a surprise when I installed it because I didn't pay attention to just how low its voltage drop is - I just knew it was better. Even more of a surprise was just how big of a deal the system it was in ended up being but that's another story...)

author: Monkeh
author_rank: Super Contributor
timestamp: February 17, 2018, 04:43:41 am
content: Quote from: NiHaoMike on February 17, 2018, 04:31:45 amhttps://patents.google.com/patent/US8148748

author: BrianHG
author_rank: Super Contributor
timestamp: February 17, 2018, 04:47:29 am
content: Ok, I picked 1 device out of a whole series which of devices which go up to 100v, 60 amps. They are brand new, but already available. I know about the poor leakage current, but when they are priced at around 1$ at digikey when a comparable schottky with an extra 100mv to 200mv at the same current and speed comes in above 7$ each, these devices have a market, even with some reverse current and capacitance limitations, they have their use and market.I'm making a 3 phase PMG 30V generator and I would rather pay 5$ using these instead of 40$ in schottky equivalent where I would still loose more wattage due to the larger voltage drop. This is a lot of money after building 1k units. After 2k units, since my original design was priced with schottky in mind, I have enough in pocket for a nice new car...I'll be going up in voltage and be using this guy 100v, 40amp guy:http://www.st.com/content/st_com/en/products/diodes-and-rectifiers/field-effect-rectifiers/ferd40h100s.htmlAt 56cents each, to hell with schottky... This lowers my diode cost from 40.00$ to 3.36$.OOOOPPPPSSS, just found some 35 amp 100v schottky from Vishay with comparable price. Schottky diodes above 35 amps for some reason sky-rocket in price.

author: BravoV
author_rank: Super Contributor
timestamp: February 18, 2018, 08:14:42 am
content: BrianHG, do a review, even brief one on how it performs, on a separate thread if you had a chance, please.