Using red LEDs with ignition voltages of the order of 1.5 V we can make a multiple voltage reference. Current is low.
This circuit that has excellent linearity using an NTC as a sensor was found in a European...
This frequency division multiplexing signal decoding circuit is from a 1980s documentation. The integrated...
This circuit is from an old publication of 1972 but can be mounted with BC548 transistors for 12 V...