I have been experimenting with an LM3914. I'd like to use this to detect the voltage across the 1/2 ohm resistor in the attached schematic. This resistor is used to bias the transistor that actuates current limiting in this power supply when current exceeds 1 Amp, that is, when the voltage drop becomes .5V or greater. Unfortunately, the resistor is not in the ground side of the circuit where I can "measure" it easily with the LM3914(by connecting it directly to pin 5). I'm considering putting another resistor in the ground side for this measurement. Is there another way to do this? I've looked through the archives and for other circuits on the 'net without finding anything similar.
Can someone explain the use of pin 8 when not grounded - as in most circuits?
Can someone explain the use of pin 8 when not grounded - as in most circuits?