This is my first post, thanks in advance any and all answers.
I'm making 10 test units which need to be field proved. The design parameters are:
1) High input impedance (at least on par with a Fluke 87, or better) input measuring from 1 to 51 milli Volts DC--accurate to within 1 millivolt. (the range might ultimately be extended to 100 milli-Volts)
2) The above, at a set value (say, 50 milli Volts) switches a D.C. inductive load up to approx. 1 Amp. (basically, one or more Bosch style relays, probably either resister or diode suppressed at the input coil) NOW.
3) A timer/delay circuit involved in, or attached to, the above which can be adjusted from approx. .5 to 3 seconds--this part so the above won't continuously cycle.
4) All the above mess powered from approx. 12-48 Volts D.C. of nasty vehicle power.
5) Polarity protection to approx. 100 amps D.C. (this last part I was thinking of simply using a big diode, easy-peasy)
I'm hoping for some industry-level, non-microprocessor prioritized chips as I want to avoid any reseting inevitabilities.
In the above, simplicity and robustness greatly trump cost. This circuit will be used in the vehicle industry, by less than careful hands.
Thanks again for all input.