The total ccs current taxes the 9610 times the input-output voltage difference. If you got individual sink for that Mosfet, make it bigger. If a common sink and still too hot, enlarge it too.
That means 3.5W dissipation on 9610 for 7V & 0.5A. Not terrible. Maybe your DAC uses less than 450mA and the output contributes more than 50mA difference. Look in the bib builds thread, they have measured those DACs real consumption in a couple of posts. Anyway will not make too much heat at 5V. Just make your sink larger.
the 9610 is hot.not the 9540.
i left it working for 1 hour and i still could touch the heatsink even it was very hot.
for is ok but in the summer i worry i little.
it`s not easy to find bigger heatsink to fit but i will try.
i have this now
Heat Sink FHS129/50,8STS :: Heat Sinks :: Electromechanical :: Electronic Parts :: Banzai Music
if somebody can recomend one i am listening.
thx.
i left it working for 1 hour and i still could touch the heatsink even it was very hot.
for is ok but in the summer i worry i little.
it`s not easy to find bigger heatsink to fit but i will try.
i have this now
Heat Sink FHS129/50,8STS :: Heat Sinks :: Electromechanical :: Electronic Parts :: Banzai Music
if somebody can recomend one i am listening.
thx.
Back, will be better if you read the Salas BiB manual to know how calculate about power disippation.
thanks i read that info some time ago and i couldn`t remember where it was.
now i found it.🙂
back,
but you can barely touch it by hand. ....the heatsink is 4k/C
As you have allowed 500mA total on your CCS with 450 of that running your dac, then only 50mA thru the shunt means it's pretty much operating at, or over, it's reasonable operating conditions with the "can't touch it " heatsink temperature.
Is 4k/C = 4 degrees Centigrade/Watt of the heatsink's rating? (ie 4*C/Watt)
As Andrew has mentioned, how much voltage drop across the regulator? (to determine the power dissipation)
but you can barely touch it by hand. ....the heatsink is 4k/C
As you have allowed 500mA total on your CCS with 450 of that running your dac, then only 50mA thru the shunt means it's pretty much operating at, or over, it's reasonable operating conditions with the "can't touch it " heatsink temperature.
Is 4k/C = 4 degrees Centigrade/Watt of the heatsink's rating? (ie 4*C/Watt)
As Andrew has mentioned, how much voltage drop across the regulator? (to determine the power dissipation)
i can`t find 2.7C/WATT heatsink so i will the case as heatsink.
i think it will do the trick.
i think it will do the trick.
You can give it 30V absolute max raw DC input and 24V out. The stop is the top cascode Jfet that has 25V max. By the time the input Mosfet drops there is about Vin-5V potential for the top Jfet. If you watch that or you got a higher max device it can go higher, no problemo. If you can find BF245C which is 30V device you could be safer for input max due to mains and trafo uncertainties regarding max raw dc input and distance to output for solid regulation.
Hi Salas,
I will keep to the 22v max then. Will build another one using bjt cascode for higher Vout.
Thanks.
I will keep to the 22v max then. Will build another one using bjt cascode for higher Vout.
Thanks.
Remember, only the top one to change. It should be twice the Vgs spec of K170 at least and give higher free IDSS than the K170 under it so to best cascode.
I don't know if it can bring problems due to much larger Cob (output capacitance). Try it until having a fast low noise high hfe TO-92 to restore.
Salas, what is the reason why you propose a 100R between output of the reg and an IC?
Why 100R?
Why 100R?
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