IRFP260N model appears to be broken

C

Chris Carlen

Guest
Hi:

I was attempting to test the substrate diode recovery characteristics as
modeled in the file I downloaded from irf.com called <irfp260n.spi>, but
the thing exhibits bizarre behavior.

Basically I tied the gate to the source to ground, and then a resistor
from the drain to a pulse source set as follows:

v1 n001 0 pulse (-1.5 10 0 10n 10n 1u 2u)

When the pulse source is set to swing more than about 0.5 below zero
volts, the FET gets stuck with its drain terminal at about -0.6V, and
stays that way even after the source has gone back to positive. After
several cycles, the diode begins switching, and exhibiting a fairly
normal 100ns recovery time.

But if you change the pulse to:

v1 n001 0 pulse (-10 10 0 10n 10n 100u 200u)

then we see radically long 40-60us recovery times.

The model file can be found here:

http://ec.irf.com/v6/en/US/adirect/ir?cmd=catProductDetailFrame&productID=IRFP260N

Here's a screen shot of the simulation compared to IRF540:

http://home.earthlink.net/~crobc/irfp260n/ltspice.png

Would the consensus be that the IRFP260N model is screwed, or is there
some logical explanation for this?

I'll have to test this device on the bench on Monday or after I take my
vacation in April to see what it really does. But I doubt it will
behave as the model indicates.

Thanks for comments.


Good day!

--
_____________________
Christopher R. Carlen
crobc@earthlink.net
Suse 8.1 Linux 2.4.19
 
"Chris Carlen" <crobc@BOGUS_FIELD.earthlink.net> schrieb im Newsbeitrag
news:c452id0iaa@enews3.newsguy.com...
Hi:

I was attempting to test the substrate diode recovery characteristics as
modeled in the file I downloaded from irf.com called <irfp260n.spi>, but
the thing exhibits bizarre behavior.

Basically I tied the gate to the source to ground, and then a resistor
from the drain to a pulse source set as follows:

v1 n001 0 pulse (-1.5 10 0 10n 10n 1u 2u)

When the pulse source is set to swing more than about 0.5 below zero
volts, the FET gets stuck with its drain terminal at about -0.6V, and
stays that way even after the source has gone back to positive. After
several cycles, the diode begins switching, and exhibiting a fairly
normal 100ns recovery time.

But if you change the pulse to:

v1 n001 0 pulse (-10 10 0 10n 10n 100u 200u)

then we see radically long 40-60us recovery times.

The model file can be found here:


http://ec.irf.com/v6/en/US/adirect/ir?cmd=catProductDetailFrame&productID=IRFP260N

Here's a screen shot of the simulation compared to IRF540:

http://home.earthlink.net/~crobc/irfp260n/ltspice.png

Would the consensus be that the IRFP260N model is screwed, or is there
some logical explanation for this?
Click to expand...
Hello Chris,
there is an error in the diode model in the IRFP260N.
D1 3 1 MD
..MODEL MD D IS=1.43789e-09 RS=0.00471658 N=1.25851 BV=200
+IBV=0.00025 EG=1.2 XTI=1.05255 TT=9.99946e-05
+CJO=3.21781e-09 VJ=2.53122 M=0.80474 FC=0.494537

They have specified a three order of magnitude too large transit time TT.
Maybe TT=1e-7...5e-7 is correct.

You could try the test circuit in the data sheet and adjust TT until you
get the specified recovery time.

I'll have to test this device on the bench on Monday or after I take my
vacation in April to see what it really does. But I doubt it will
behave as the model indicates.
Click to expand...
Please let us know your results.

Best Regards,
Helmut



..SUBCKT irfp260n 1 2 3
**************************************
* Model Generated by MODPEX *
*Copyright(c) Symmetry Design Systems*
* All Rights Reserved *
* UNPUBLISHED LICENSED SOFTWARE *
* Contains Proprietary Information *
* Which is The Property of *
* SYMMETRY OR ITS LICENSORS *
*Commercial Use or Resale Restricted *
* by Symmetry License Agreement *
**************************************
* Model generated on Dec 1, 00
* MODEL FORMAT: SPICE3
* Symmetry POWER MOS Model (Version 1.0)
* External Node Designations
* Node 1 -> Drain
* Node 2 -> Gate
* Node 3 -> Source
M1 9 7 8 8 MM L=100u W=100u
* Default values used in MM:
* The voltage-dependent capacitances are
* not included. Other default values are:
* RS=0 RD=0 LD=0 CBD=0 CBS=0 CGBO=0
..MODEL MM NMOS LEVEL=1 IS=1e-32
+VTO=4.36308 LAMBDA=9.43213 KP=24.971
+CGSO=3.81166e-05 CGDO=1e-11
RS 8 3 0.026764
D1 3 1 MD
..MODEL MD D IS=1.43789e-09 RS=0.00471658 N=1.25851 BV=200
+IBV=0.00025 EG=1.2 XTI=1.05255 TT=9.99946e-05
+CJO=3.21781e-09 VJ=2.53122 M=0.80474 FC=0.494537
RDS 3 1 1e+06
RD 9 1 0.0001
RG 2 7 6
D2 4 5 MD1
* Default values used in MD1:
* RS=0 EG=1.11 XTI=3.0 TT=0
* BV=infinite IBV=1mA
..MODEL MD1 D IS=1e-32 N=50
+CJO=7.55868e-09 VJ=0.627882 M=0.9 FC=1e-08
D3 0 5 MD2
* Default values used in MD2:
* EG=1.11 XTI=3.0 TT=0 CJO=0
* BV=infinite IBV=1mA
..MODEL MD2 D IS=1e-10 N=0.400098 RS=3e-06
RL 5 10 1
FI2 7 9 VFI2 -1
VFI2 4 0 0
EV16 10 0 9 7 1
CAP 11 10 9.32192e-09
FI1 7 9 VFI1 -1
VFI1 11 6 0
RCAP 6 10 1
D4 0 6 MD3
* Default values used in MD3:
* EG=1.11 XTI=3.0 TT=0 CJO=0
* RS=0 BV=infinite IBV=1mA
..MODEL MD3 D IS=1e-10 N=0.400098
..ENDS irfp260n
 
Helmut Sennewald wrote:
"Chris Carlen" <crobc@BOGUS_FIELD.earthlink.net> schrieb im Newsbeitrag
news:c452id0iaa@enews3.newsguy.com...

Would the consensus be that the IRFP260N model is screwed, or is there
some logical explanation for this?


Hello Chris,
there is an error in the diode model in the IRFP260N.
D1 3 1 MD
.MODEL MD D IS=1.43789e-09 RS=0.00471658 N=1.25851 BV=200
+IBV=0.00025 EG=1.2 XTI=1.05255 TT=9.99946e-05
+CJO=3.21781e-09 VJ=2.53122 M=0.80474 FC=0.494537

They have specified a three order of magnitude too large transit time TT.
Maybe TT=1e-7...5e-7 is correct.
Click to expand...
I see. That wasn't very nice of them.

You could try the test circuit in the data sheet and adjust TT until you
get the specified recovery time.
Click to expand...
Excellant idea.

Thanks for the reply. I'm not well versed in device model parameters,
so the help is greatly appreciated.

Please let us know your results.

Best Regards,
Helmut
Click to expand...
Will do.

Good day!



--
_____________________
Christopher R. Carlen
crobc@earthlink.net
Suse 8.1 Linux 2.4.19
 
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