05-01-2026, 09:58 PM
Ron
I put the calculation in another thread here just a week ago for that very circuit.
The 150F is the op temp, but that without a heatsink will be quickly exceeded even at 25C ambient at 62.5C/W with 2W dissipation.
The current could be way more as long as the voltage drop is way less.
At 70mA you will dissipate 1W at 14V dropout and 2W at 28V dropout.
So, I understand, the dropout is really small, like 10V or so?
I put the calculation in another thread here just a week ago for that very circuit.
The 150F is the op temp, but that without a heatsink will be quickly exceeded even at 25C ambient at 62.5C/W with 2W dissipation.
The current could be way more as long as the voltage drop is way less.
At 70mA you will dissipate 1W at 14V dropout and 2W at 28V dropout.
So, I understand, the dropout is really small, like 10V or so?
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
![[-]](https://philcoradio.com/phorum/images/bootbb/collapse.png "[-]")
