tooler
New Head-Fier
- Joined
- Jun 21, 2001
- Posts
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I'm working on the Szekeres amp right now and I'm trying to determine a good guess for how much resistance I should dial in for R3 so that Vds is half my power supply voltage.
To do this, I figured I could dust off the circuits book I never thought I'd use and plug in some values for the DC analysis equations. However, all the equations I have in this book require Vgs, which usually requires some information about the transconductance and threshold voltage of the MOSFET. I looked at a data sheet for the IRF513, but didn't find exactly what I needed. The threshold voltage Vtn (listed as Vgs(th)) is a range and doesn't list a typical value. I don't see anything I could use for Kn, which is in A/(V^2). Where do I get useful information for the equation,
Vgs = Kn/2(Vgs-Vtn)^2
Or should I use some other equations?
I'd like to know how to apply my worthless book knowledge to real-world situations like this. I'm really curious and I think it will help me in the future.
P.S. I got a weird feeling of deja-vu that I asked this before, but nothing turned up in a search on here or HeadWize.
To do this, I figured I could dust off the circuits book I never thought I'd use and plug in some values for the DC analysis equations. However, all the equations I have in this book require Vgs, which usually requires some information about the transconductance and threshold voltage of the MOSFET. I looked at a data sheet for the IRF513, but didn't find exactly what I needed. The threshold voltage Vtn (listed as Vgs(th)) is a range and doesn't list a typical value. I don't see anything I could use for Kn, which is in A/(V^2). Where do I get useful information for the equation,
Vgs = Kn/2(Vgs-Vtn)^2
Or should I use some other equations?
I'd like to know how to apply my worthless book knowledge to real-world situations like this. I'm really curious and I think it will help me in the future.
P.S. I got a weird feeling of deja-vu that I asked this before, but nothing turned up in a search on here or HeadWize.