Tokin SIT low voltage high current curves

woofertester

Member
2011-06-25 10:31 pm
ItsAllInMyHead has been kind enough to loan me a pair of Tokin SITs to curve trace.

Here is the first installment. Current limit for this set of curves is 1.5A

Vgs for curves from left to right -1.5, -2.0, -2.5, -3.0, -3.5
 

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what's practical - 3 to 3A5 max and 35-40V

no more needed

I did play with M. Rothacher's model making thingy lately and I did pretty close looking/working model for 2SK77B

will do the same for THF51S and/or 2SK182ES , as soon you boys publish some curves

frankly , I didn't even though about doing them (curves) , even if I don't have a tracer ...... done that dozen times for toobz , so sorta used to make them old school way
 
whoa!

it seems you're versatile with that :)

see 2SK77B graph ... tnx to AnthonyA , shown here : Tokin 2SK77B datasheet | Zen Mod Blog

also attached ......

I know I'm Greedy and Naughty Boy ....... can you give me more ......... as much you're confident it's safe with your testing procedure

so , gate v. step 1V, starting from 0 , and V and A whatever you choose max

:clown:
 

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The family of curves that you posted is power limited to 300 watts and Vds extends to 100V. The equipment that produced these curves was a very expensive piece of equipment.

The equipment that I am using is limited to 40V Vds when testing high (above 1.5A) current. When testing above 40V, the current is limited to 1A.

I can go very much above 4A (up to 50A) when below 40V. How much current do you want to see below 40V? My thinking would be that you will be biasing these devices at at 2A to 3A maximum.


whoa!

it seems you're versatile with that :)

see 2SK77B graph ... tnx to AnthonyA , shown here : Tokin 2SK77B datasheet | Zen Mod Blog

also attached ......

I know I'm Greedy and Naughty Boy ....... can you give me more ......... as much you're confident it's safe with your testing procedure

so , gate v. step 1V, starting from 0 , and V and A whatever you choose max

:clown:
 
I have built an amplifier similar to the SIT-2 using Tokin 2SK182ES devices. With the particular FETs used I found it necessary to use Vds voltages greater than 50V in order to obtain a second harmonic sweet spot with a 6 Ohm load and 1.6A bias. The two SITs have rather different parameters, requiring different bias currents and idle Vds settings in order to get the THD vs. Watts curves shown below:
 

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I have built an amplifier similar to the SIT-2 using Tokin 2SK182ES devices. With the particular FETs used I found it necessary to use Vds voltages greater than 50V in order to obtain a second harmonic sweet spot with a 6 Ohm load and 1.6A bias. The two SITs have rather different parameters, requiring different bias currents and idle Vds settings in order to get the THD vs. Watts curves shown below:

What was your power supply voltage total at the top of the current source?

80 watts dissipation for the SIT? How hot does the SIT become?

You always have interesting projects.
 
I am using 94V power supplies (one per channel) and low-speed, low-noise fan cooling. The fans run at about 600RPM, with heatsink temperatures of less than 45C directly under the SITs. Below are some pictures:


What was your power supply voltage total at the top of the current source?

80 watts dissipation for the SIT? How hot does the SIT become?

You always have interesting projects.
 

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