1.75A bias at 24Vdc rails means ~40W dissipation for each of the output devices.
Assuming a heatsink that's large enough to be at 50C ;
-with kerafol red insulators, lower than 90C die temperature.
-with mica insulators, around 95C
Both work, around 87.5C die temperature is the optimum for Class A devices.
Assuming a heatsink that's large enough to be at 50C ;
-with kerafol red insulators, lower than 90C die temperature.
-with mica insulators, around 95C
Both work, around 87.5C die temperature is the optimum for Class A devices.
Well I was thinking of plain F5, so 18V rails
For 24v rails on the Turbo article (pre-v1), Papa specifies 5W resistors and cascoding the input stage to protect it from overvoltage.
Anyway, It s summer here in Greece, so keeping the sinks @50 celcius is going to be really tough...
At least without kicking the A/C into high gear...
For 24v rails on the Turbo article (pre-v1), Papa specifies 5W resistors and cascoding the input stage to protect it from overvoltage.
Anyway, It s summer here in Greece, so keeping the sinks @50 celcius is going to be really tough...
At least without kicking the A/C into high gear...
Smarter choice in countries as Greece is to go forced convection with fans, or much better, water cooled.
A 80x400mm heat exchanger costs € 50-60.
At 0.1m/s water velocity, heatsink temperature would be less than 5C higher than ambient.
(the smallest aquarium pump would be more than sufficient, €10-15)
A 80x400mm heat exchanger costs € 50-60.
At 0.1m/s water velocity, heatsink temperature would be less than 5C higher than ambient.
(the smallest aquarium pump would be more than sufficient, €10-15)
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24V rails is standard on F5. F5turbo V1 and V2 is 32V
you don't need to cascode the input with rails under 30V🙂
Ah yeah... I was thinking 18V transformers... pfff.... I really need a break from work to dedicate myself to DIY 😀 😛
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