Hitachi Laterals have a datasheet transconductance figure of 1-1.5 Sie(menot)
For the 8A max (they can do a whole lot more peak output, but that's another bedtime story) output current number they'd drop an extra ~5.3V to 8V between gate and source.
With additional Vgs losses of that magnitude, why bother with diodes ?
(plus, with reasonably matching Lateral output devices, there's no need for 0R47 source resistors, 8 amps across a 0R22 is a mere 1.76V droopy)
Hello
I plan to make a F5 turbo V1, on the plan the resistances of triggers mosfet (R13 to R16) are of values 47,5 ohms. In the series Dale RN60 1 / 4W 1 %, I have the choice between two values: 49,9 ohms or 44,2 ohms. Which of both values is the best adapted
Thank you for your help
Cordially
I plan to make a F5 turbo V1, on the plan the resistances of triggers mosfet (R13 to R16) are of values 47,5 ohms. In the series Dale RN60 1 / 4W 1 %, I have the choice between two values: 49,9 ohms or 44,2 ohms. Which of both values is the best adapted
Thank you for your help
Cordially
not realy. if you got +/-100V rails, then you want some higher then 10K.
100/(10K+4.75K)X4.75K=32.2V.
100/(47.5K+4.75K)x4.75K=9.1V
100/(10K+4.75K)X4.75K=32.2V.
100/(47.5K+4.75K)x4.75K=9.1V
Can you elaborate on what effect this has on cascade. I am still trying to figure this out. It's not symmetrical, so it's hard to figure.
One for 32v and 50v would be good examples.
If you go to this thread: http://www.diyaudio.com/forums/pass-labs/207103-f5-turbo-builders-thread-14.html#post2979218
And read before and after Jacco's post.
If the link doesn't take you, it is the "F5 Turbo Builders Thread" page 14 at 10 posts per page.
It is supposed to be symmetrical, Papa was probably showing the extreme values for high and low rail voltage, both R25 and R26 should be equal.
Rush
cascode referance voltage = rail voltage/(R25+R27)xR27
so for 50V rails it will be:
50/(10K+4.75K)x4.75K= 16.1V
for 32Vrails:
32/(10K+4.75K)x4.75K= 10.3V
so for 50V rails it will be:
50/(10K+4.75K)x4.75K= 16.1V
for 32Vrails:
32/(10K+4.75K)x4.75K= 10.3V
Guys any F5T topology suggestions for 1.7 maggies?
I m looking for a more educated opinion from people who are more experienced with how the F5T might actually perform with such difficult loads (math aside).
I m looking for a more educated opinion from people who are more experienced with how the F5T might actually perform with such difficult loads (math aside).
http://www.diyaudio.com/forums/pass-labs/182966-f5-low-z-loads.html
Might be some interesting stuff here. Predates the article a little but the same as Version 1 I guess. They;'ll be some updates in a week or two...
Sorry but I think no one has much experience with the Turbo.
My 2 cent with F5 on 4 homs PolkLSi15 (probably easier load)
Think about big heat sink and then duble that go for 4 or more mosfets on each suply rail crank up bias as much as sink can cope (top of head figure is no more than 50 W dissipation on each mosfet)
I have F5 running on twin whitout the current limiters and it works preaty well with polks
My 2 cent with F5 on 4 homs PolkLSi15 (probably easier load)
Think about big heat sink and then duble that go for 4 or more mosfets on each suply rail crank up bias as much as sink can cope (top of head figure is no more than 50 W dissipation on each mosfet)
I have F5 running on twin whitout the current limiters and it works preaty well with polks
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