Alternate FET's for 41Hz AMP2

[gmikol]

So I have an AMP2 kit that I haven't started building yet, but I'm going for a high power application. The board doesn't have space for 4 additional FETs, so I've been looking at some devices with lower Rds(on) than the stock STW34NB20.

Here's what I'm looking at:

STW40N20
STW75N20

These both have low Qg and lower Rds(on) than the stock devices, and good switching times & reverse recovery charge.

Other options are:
IRFP4227
IRFP4229
IRFP4332

These look good on paper, but the data sheets don't have switching times, just a "shoot-through blocking time" spec of 100ns.

I don't have a scope to evaluate the options according to the recommendations in Tripath AN-16. So I'm hoping somebody out there has some experience with these devices. Anybody in the Portland, OR area got a 'scope to share?

--Greg

 

[Markus2006]

Please cheeck the documentation of the kit. It seems to me that additional space is provided if you want to implement high-power amp with low-current transistors (using 4 of them). If you want to use high-current transistors, you may still use two of them.
Does the board have space for 4 additional transistors or just for 2? And 4 would be the total number?

I think that STW series is a good choice but I haven't check it yet.

Marek

 

[gmikol]

Nope...the board I have is basically the RB-TK2350 board. There's only room for 4 transistors (2 per channel). So that's why I'm looking for the lowest Rds devices I can find.

--Greg