avr_fred:
Nothing to do with a Darlington. It's just two switches, an inverter (npn) driving a high side switch (pnp) for the relay. Nothing more, nothing less.
i see.
and to think i'm attempting to understand the myriad of op-amp configs, i haven't even fully grasped transistors yet !!
ChrisTenone:
For a darlington, imagine two npn transistors, where the emitter of the first feeds into the base of the second, and the collectors both go to the supply.
ahh yes - that's the difference... i was just going by the 'base' connected to the other.
Thanks ! 