Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

What is Crss of this FET (ipa65r280e6)?

Status
Not open for further replies.

treez

Advanced Member level 5
Joined
Sep 22, 2008
Messages
7,893
Helped
578
Reputation
1,159
Reaction score
557
Trophy points
1,393
Location
cambridge
Activity points
78,105
IPA65R280E6
https://www.infineon.com/dgdl/Infin...n.pdf?fileId=db3a304328c6bd5c0128d3bdf1ca009e


..Datasheet does not say, Crss is needed to calculate the length of the miller plateau interval.

- - - Updated - - -

Woops, sorry, info found in graph lower down in datasheet...now solved

- - - Updated - - -

Hello,
As you know, when investigating FET (turn ON) switching losses in offline flybacks, it is nice to be able to calculate the miller charge time, since for the duration of the miller plateau interval, the FET is in the linear region, and the energy dissipated is 0.5 x Vds(off) * I(pri_pedestal) * [duration of miller plateau].

The way to calculate the miller plateau interval, would be using dt = (C.dv)/I

…where
dv = ds(off)
I = current from gate driver.
C = Crss = Cgd

However, “Crss” is highly variable as the voltage across it varies, the magnitude of Crss to be used in the above equation would be a research issue.

Given that we are using the FET IP65R280E6, what value would you use for the value of “Crss” in the above equation?
Page 12 of the datasheet gives the value of Crss in relation to the voltage across it, but as you can see, it varies over several orders as Vds varies down to zero volts

IP65R280E6 datasheet:
https://www.infineon.com/dgdl/Infineon-IPA65R280E6-DS-v02_01-en.pdf?fileId=db3a304328c6bd5c0128d3bdf1ca009e
 

FvM

Super Moderator
Staff member
Joined
Jan 22, 2008
Messages
48,275
Helped
14,226
Reputation
28,713
Reaction score
12,920
Trophy points
1,393
Location
Bochum, Germany
Activity points
279,559
You'll preferably use effective Crss numbers that can be derived from the gate charge diagram.
 

Status
Not open for further replies.

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Top