Please confirm IGBT only conducts in one direction

[cupoftea]

Hi,
Please just for reality check just confirm current can only go one way in IGBT?

IKW30N65EL5

https://www.infineon.com/dgdl/Infineon-IKW30N65EL5-DataSheet-v02_02-EN.pdf?fileId=5546d4624b0b249c014b11cd5d3c3acb

 

[Easy peasy]

Normally the IGBT has an added diode chip in its package for use in situations where it is needed, a standard IGBT gives you the freedon to add your own choise of reverse diode, but there are now IGBTs with intrinsic body diodes being made

(PDF) A new high voltage shorted-anode IGBT with intrinsic body diode improves performance of single-ended induction cooker

PDF | Nowadays the field-stop (FS) IGBT provides lower saturation voltage drop and lower switching losses than the conventional non-punch-through (NPT)... | Find, read and cite all the research you need on ResearchGate

www.researchgate.net

somewhat similar to the common mosfet - which does always have an intrinsic body diode ( and parastic BJT causing latchup some times )

--- Updated Sep 5, 2021 ---

A picture of the internals ...

--- Updated Sep 5, 2021 ---

and:

https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=&ved=2ahUKEwi-kO-w8OjyAhUnzjgGHavZCEwQFnoECAMQAQ&url=https%3A%2F%2Fwww.onsemi.jp%2Fpub%2Fcollateral%2Fan-4155jp.pdf&usg=AOvVaw0SreXxnkJNGJHy8rWPy8eP

 

[cupoftea]

Thanks,
We have a reverse recovery problem in our igbt's on-body diode, so an igbt with no diode woudl be great for us.

There seems no way in digikey to sort the ones with diode, from the ones without diode.
We need to use one without diode, but with two paralleled sic diodes added by us. (sic for no rev rec)

We are currently using the IKW30N65, but it has the nuisance added diode.

 

[KlausST]

Hi,

How do you know that there is a "reverse recovery" problem?
And in what magnitude?

What I did:
* internet search "IKW30N65"
* found some distributors
* selected "Digi-key" (the first one, randomly)
* they show a table with 5 different "IKW30N65".
* and in the table there is a column with "reverse recovery time". That´s what you are looking for.
* all 5 types with different trr values. So your part number is not complete. It misses the exacle the information what you are looking for.

So we don´t have the information about your trr. We can not recommend faster ones.

******

What I did next:
* Digi-key search for "single IGBT"
* select for: >650V, >30A, TO220, Infineon
* sorted for increasing trr
* The fastest ones show "25ns", pretty fast I think.
* But there are many that show "-" in the trr column.
* I had an idea "why".
* so I clicked on the "datasheet" button of one with similar name as yours: "IGP30N65F5XKSA1-ND"
* datasheet first page symbol shows no diode
* datasheet first page text says: "•Ideal fit with SIC Schottky Diode in boost converters"

All in all it took about 2 min of using the internet.
Writing this post took much longer.

Klaus

Not done, but also possible solutions:

* go to other distributors and do search

Done:
* Infineon product search:

--> Press the link "without antiparallel diode" --> https://www.infineon.com/cms/en/pro...es/discrete-igbt-without-anti-parallel-diode/

****

* internet search "igbt SiC diode 650V"
--> found an article where INFINEON builds IGBT with internal fast SiC diode.
I did not spent more time to find out partnames.

 

[Easy peasy]

IGBTs' can turn on very fast, < 15nS, if you slow the gate drive on your existing system your issues with possible Trr & Irr may go away ....

--- Updated Sep 6, 2021 ---

--- Updated Sep 6, 2021 ---

One without diode:

IXXH30N65B4 IXYS | Discrete Semiconductor Products | DigiKey

Order today, ships today. IXXH30N65B4 – IGBT PT 650 V 65 A 230 W Through Hole TO-247 (IXXH) from IXYS. Pricing and Availability on millions of electronic components from Digi-Key Electronics.

www.digikey.co.nz

 

[mtwieg]

Thanks,
We have a reverse recovery problem in our igbt's on-body diode, so an igbt with no diode woudl be great for us.

Just keep in mind that if you're truly seeing reverse recovery behavior, then even if you do use an IGBT without an integrated diode, you will very likely need to add your own external diode. But you can choose the best one for your needs.

There seems no way in digikey to sort the ones with diode, from the ones without diode.

Indeed, that is annoying.

We need to use one without diode, but with two paralleled sic diodes added by us. (sic for no rev rec)

Maybe you could just use a SiC MOSFET instead of the IGBT?

 

[cupoftea]

Thanks, yes, i am able to find igbts with and without diode, but the key point appears to be that igbts without diode are rather rarer and possibly not a good idea to put in the BOM, as there may well be supply issues?

Its difficult to assess how rare the "no diode" ones are.

 

[KlausST]

Hi

Indeed, that is annoying.

As hinted in post#23: Look for the IGBTs with "-" in the column trr.

Klaus

 

[cupoftea]

Isn't it strange that for say 20kHz converters, we dont see 1200v igbt's in parallel, instead of single 650V devices which may not have the surge voltage rating.
So, Why dont we see, say two IGBTs in parallel, being driven by the same gate driver, in 2kW switch mode converters at 20khz fsw?

Surely there's no reason that they can't be paralleled, as long as enough damping is put on the gates?

Although many have a negative temp co and so paralleling would be bad for those ones.

 

[Easy peasy]

at 2kW and 20kHz, mosfets are considerably lower loss .....

 

[D.A.(Tony)Stewart]

IGBT's since they have BJT outputs are NTC in linear region yet slightly PTC when saturated and approx NPO at 10% rated current. They are lower capacitance out yet FET's have lower RdsON than BJT's Rce for same size chip.

losses are sum of static and dynamic from charging slew rates


Imagine Rce tempco as the difference between PN junctions for CB vs BE as both are saturated with declining hFE current ratios for increasing saturation.

GaN FETs promise to be 30x faster at HV when processes improve.

Si is already very mature with over 7 generations of design at Mitsubishi.