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fairchild mosfet taken from Mean Well TN 1500 inverter.
- Thread starter aoud
- Start date
KrisBlueNZ
Sadly passed away in 2015
Hi there and welcome to Electronics Point 
The 12N60 is an N-channel power MOSFET. It's available in several different packages, with slightly different specifications. The basic specifications for the biggest package are:
Drain current 12A (48A peak) (max allowed)
Drain-source voltage 600V (max allowed)
Power dissipation 225W (max allowed)
Gate-source threshold voltage 5V max
Gate-source ON resistance 0.65Ω max
Gate charge 42 nC typical
Reverse transfer capacitance 25 pF typ, 35 pF max
It is listed at Digi-Key (http:/www.digikey.com) but only the TO-220 package version is stocked.
Can you upload a photo of it, or another identical one in the unit, so we know what package you have.
Do you know what caused it to fail?
The 12N60 is an N-channel power MOSFET. It's available in several different packages, with slightly different specifications. The basic specifications for the biggest package are:
Drain current 12A (48A peak) (max allowed)
Drain-source voltage 600V (max allowed)
Power dissipation 225W (max allowed)
Gate-source threshold voltage 5V max
Gate-source ON resistance 0.65Ω max
Gate charge 42 nC typical
Reverse transfer capacitance 25 pF typ, 35 pF max
It is listed at Digi-Key (http:/www.digikey.com) but only the TO-220 package version is stocked.
Can you upload a photo of it, or another identical one in the unit, so we know what package you have.
Do you know what caused it to fail?
Thanks for your reply . I uploaded a photo of the mosfet. The inverter had loose coil ends I took it for repair and they replaced a capacitor as well . It turned on and looked ok . Once home I turned it on and heard a quick noise similar to fuse . Took it back to the shop and now they say it had 2 bad mosfets and three burned fuses .
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KrisBlueNZ
Sadly passed away in 2015
That's a TO-247 package, and Fairchild don't make the 12N60 MOSFET in TO-247. It's probably an IGBT, part number HGTG12N60A4D. Digi-Key and Mouser both have it listed, but it is not available, and is flagged as NRND (not recommended for new designs).
I'm not experienced with IGBTs so I'll ask Steve to recommend a suitable replacement. The data sheet is attached to this post. It's the TO-247 version.
I'm not experienced with IGBTs so I'll ask Steve to recommend a suitable replacement. The data sheet is attached to this post. It's the TO-247 version.
That would have been just too easy... Sadly, not the case.
Looking at that device, one important thing is the integral "hyperfast" diode.
Looking at digikey, there are no devices they have in stock which match or exceed the performance of this device. The closest are here. Note that the 12N60 is listed there with 0 stock.
The difference between the parts that are in stock and the one you want to replace is the reverse recovery time. This is due to the 12N60 having an integral hyperfast diode. To emulate this you would need an additional external diode capable of the full current, however the average current would be much lower. Here are a list of possible diodes. You would want to check that the diode is capable of maybe 100A peak currents -- and from that you'd need the datasheet. Looking at the cheapest option. This might be acceptable.
You would need to connect the diode directly across the IGBT's pins if possible and mount it on a heatsink (the same one as the IGBT would be fine). It may require insulation -- I'm not certain if the one I suggested has an isolated tab.
But again, I've looked at this very narrowly. Whilst the IGBT may be toast, there may be another fault that will toast a replacement instantly. It can get expensive if you need to keep replacing devices as you track down a fault.
Looking at that device, one important thing is the integral "hyperfast" diode.
Looking at digikey, there are no devices they have in stock which match or exceed the performance of this device. The closest are here. Note that the 12N60 is listed there with 0 stock.
The difference between the parts that are in stock and the one you want to replace is the reverse recovery time. This is due to the 12N60 having an integral hyperfast diode. To emulate this you would need an additional external diode capable of the full current, however the average current would be much lower. Here are a list of possible diodes. You would want to check that the diode is capable of maybe 100A peak currents -- and from that you'd need the datasheet. Looking at the cheapest option. This might be acceptable.
You would need to connect the diode directly across the IGBT's pins if possible and mount it on a heatsink (the same one as the IGBT would be fine). It may require insulation -- I'm not certain if the one I suggested has an isolated tab.
But again, I've looked at this very narrowly. Whilst the IGBT may be toast, there may be another fault that will toast a replacement instantly. It can get expensive if you need to keep replacing devices as you track down a fault.
That sucks when the same part number is used for two different types of devices that can be far too easily confused for each other. Even if you have a good one it's not entirely trivial to distinguish between them (you need more than a multimeter!)
KrisBlueNZ
Sadly passed away in 2015
Thanks very much for your guidance Steve.
BTW the reason for the partly overlapping part numbers could be that the IGBTs were made by Harris (at least, the data sheet looks like a Harris data sheet with Fairchild added at the top).
So it looks like it may not be worth trying to repair the inverter, as there's probably more wrong with it than just the IGBT, and there is no drop-in replacement IGBT.
BTW the reason for the partly overlapping part numbers could be that the IGBTs were made by Harris (at least, the data sheet looks like a Harris data sheet with Fairchild added at the top).
So it looks like it may not be worth trying to repair the inverter, as there's probably more wrong with it than just the IGBT, and there is no drop-in replacement IGBT.
It's hard to say. But once you've made that determination you've got less to lose and you may as well give it a shot.
I would be tempted to get a cheap IGBT with sufficient voltage rating and just try it at low power (maybe a few tens of watts) and see if it suffers. If another fault really did bring the IGBT down, then it's likely to show up pretty quickly.
If I was brave I'd ramp up the power to maybe several hundred watts (resistive load).
It's likely that the fast diode was there for a reason, but another issue is that IGBT's are subject to a latch issue due to the equivalent of an SCR that is buried inside their silicon. I'd have to go research it again to remind myself what contributes to turning this on, but I do know that more modern IGBTs are less likely to exhibit this mode of operation. Ignoring the fast diode gives you some relatively cheap options even at full power.
KrisBlueNZ
Sadly passed away in 2015
There you go, aoud. What Steve said!
Having done a little more research (reminding myself of what I have forgotten), there are some important factors to consider:
- You need an IGBT with an integral reverse diode (these are often called FRED -- Fast Recovery Epitaxial Diode -- devices, or just note in the datasheet that they have the integral diode)
- Latchup: "If latchup is not terminated quickly, the IGBT will be destroyed by the excessive power dissipation. IGBT has a maximum allowable peak drain current (ICM) that can flow without latchup. Device manufacturers specify this current level in the datasheet. Beyond this current level, a large enough lateral voltage drop will activate thyristor and thelatchup of IGBT." So, shorting the output (or some other high current peak) could have caused latchup which could easily destroy the device (pure conjecture)
I can't thank you enough for all the information you provided. I am sure the repair guy has no clue . I live in Marrakech Morocco by the way . Technicians here are just too few with very little knowledge. . I hate to just give up. perhaps if you can guide me to a specific parts I should try , possibly with picture . I should add here that you help and guidance is priceless and I am grateful for that.
hello mr steve . I am surprised and sad to see mr krisblue has passed . May God bless his soul. I decided after all this time to try again and look for that mosfet and this is the closest i seen but i have no idea if it will work .
https://www.utsource.net/ic-datasheet/12N60A4D-1551777.html
Please let me know . And thanks again
Last edited by a moderator:
If you can get hold of these, then it's worth a shot.
I'll have to go back over the thread to see what I meant by a "low power test".
Meanwhile... how long would it take you to get these?
edit: OK, not much more information.
NOTE: in most cases the way to replace these is to mount them on the heatsink, THEN solder them. This ensures that the leads are not put under stress.
What I would do after replacing the IGBT's is to power the circuit with an incandescent light bulb in series with the incoming power. Start with something like 25W if you can get one.
A good result is if the bulb lights up to some extent then gets dimmer.
If this works, measure the output voltage.
If this is OK, connect a very small load. Something that would consume under 1W. See how it works.
Before going further, ensure that the devices are correctly connected to the heatsinks and have a thin smear of thermal paste between them and the heatsink..
If everything has gone well so far, replace the bulb with a 100W bulb and try a load of about 10W.
If it's still OK, try running it connected directly to the mains on a moderate load (say 25% of the rated load), increasing it gradually to maybe 75%. I would be cautious of going further.
I'll have to go back over the thread to see what I meant by a "low power test".
Meanwhile... how long would it take you to get these?
edit: OK, not much more information.
NOTE: in most cases the way to replace these is to mount them on the heatsink, THEN solder them. This ensures that the leads are not put under stress.
What I would do after replacing the IGBT's is to power the circuit with an incandescent light bulb in series with the incoming power. Start with something like 25W if you can get one.
A good result is if the bulb lights up to some extent then gets dimmer.
If this works, measure the output voltage.
If this is OK, connect a very small load. Something that would consume under 1W. See how it works.
Before going further, ensure that the devices are correctly connected to the heatsinks and have a thin smear of thermal paste between them and the heatsink..
If everything has gone well so far, replace the bulb with a 100W bulb and try a load of about 10W.
If it's still OK, try running it connected directly to the mains on a moderate load (say 25% of the rated load), increasing it gradually to maybe 75%. I would be cautious of going further.
Last edited:
Thank you mr steeve . What i am looking for is not to have to worry about loads . Is there something you see on this site here that will solve my problem : http://www.infineon.com/cms/en/prod...html?channel=5546d4614937379a01499f71c81c0c9f
Pardon my ignorance Mr steeve i guess what i am trying to say is if i can use mosfet that will for certain do the job . I could start looking for it . I have no idea how they differ from each other . So many names and kinds is confusing . For now i am looking at 12n60a4d to 247 but that comes with names like IGBT and HTGT .
I
http://m.ebay.com/itm/1PCS-IGBT-FAI...HGTG12N60A4D-12N60A4D-G12N60A4D-/272263611081
I see this one on ebay . As i am looking for 12n60a4d to 247 . But the writing on top of mosfet says f 1J12BF and that i have no idea what it is :
http://m.ebay.com/itm/1PCS-IGBT-FAI...HGTG12N60A4D-12N60A4D-G12N60A4D-/272263611081
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