/diy/ - Do It Yourself

>>1218648
Found it, 3.8..3.9V @ 35mA, 25°C and -2mV/K. Worst case at -20°C in winter: 3.9+45*2mV=4V, harmless.
Erm.. I would use resistors.
The six 20mA as three groups of two in series, the two 30mA in parallel or single and the 35mA alone. Since you have constant 5V there's nothing to gain, neither from regulation nor energy-wise.

>does it not rely on the beta?
It does, but very little. You don't need to drive it down to B=10 or 20 like you would for Uce = 50mV (I use the BC337-40 in such cases, pic). What's really annoying is the 0.6V loss for the current sense resistor. There must be a solution and there is a solution. I need a coffee..