Quick question while I'm waiting on parts, what are you all using for insulation between the hockey puck and the heatsink?
Fellow Ohioan 🙂
I didn't use anything to insulate the hockey puck, it's isolated. I used thermal goop for the thermal interface.
I didn't use anything to insulate the hockey puck, it's isolated. I used thermal goop for the thermal interface.
Cat Skin Mk III
I have taken Generg's idea of biasing up the bottom mosfet using voltage taken from the drain of bottom mosfet, and taken it one step further and added a modulated regulated supply.
R12 is a 5k trimpot which turns on bottom mosfet.
Just throwing out ideas here. Quite a few different ways to do this.
I have a stack of bipolar transistors that will never be used in an amp circuit so I'm probably going to use them to make a regulated supply.
I have taken Generg's idea of biasing up the bottom mosfet using voltage taken from the drain of bottom mosfet, and taken it one step further and added a modulated regulated supply.
R12 is a 5k trimpot which turns on bottom mosfet.
Just throwing out ideas here. Quite a few different ways to do this.
I have a stack of bipolar transistors that will never be used in an amp circuit so I'm probably going to use them to make a regulated supply.
@ 2pico - very nice circuit.
Very interested in this thread. I could not bias past 1A with my P to P. I think everything was too spread out. I'm guessing that everything has to be very tight.
Board looks interesting.
Best to everybody
Bob
Very interested in this thread. I could not bias past 1A with my P to P. I think everything was too spread out. I'm guessing that everything has to be very tight.
Board looks interesting.
Best to everybody
Bob
I am using 160N20P, which in the grand scheme of things is virtually the same, maybe 15% different. Certainly good enough.
Best bang for the buck. Antek AS 400VA series. You'll need 2 of them.
26V secondaries would be in the ball park for a regulated supply
I have taken Generg's idea of biasing up the bottom mosfet using voltage taken from the drain of bottom mosfet, and taken it one step further and added a modulated regulated supply.
R12 is a 5k trimpot which turns on bottom mosfet.
Just throwing out ideas here. Quite a few different ways to do this.
I have a stack of bipolar transistors that will never be used in an amp circuit so I'm probably going to use them to make a regulated supply.
Hi Pico,
I would not bias the bottom MOSFET in this way with these parts having such a great transconductance.
I did it only to show how smallest Vgs changes have big effects.
The only thing I would trust is Zen Mods servo solution!
He was so friendly to develop it for me, but I am afraid It will be autumn since I start the BAF2025 amp.
Hello Brother
Yes I understand the issues with the devices, I've had a chance to play with them, however I'm starting to think your original idea may actually work, since the more the bottom mosfet turns on the lower the voltage at the drain becomes which in turn lowers Vgs which stops it running away.
It has some level of self biasing.
Subconciously you were a genius you just didn't know it yet.
😀
Anyway I will test it out point to point first.
Yes I understand the issues with the devices, I've had a chance to play with them, however I'm starting to think your original idea may actually work, since the more the bottom mosfet turns on the lower the voltage at the drain becomes which in turn lowers Vgs which stops it running away.
It has some level of self biasing.
Subconciously you were a genius you just didn't know it yet.
😀
Anyway I will test it out point to point first.
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