If anyone know how to do it as properly work version in EveryCircuit please HELP ME.
Simple circuit for inductance meassure. But I can't setting this for properly work of relaxation oscillator like in the HC14 datasheet. How to do emulate of Schmitt trigger... Also I see RC filter doesn't work properly (all the time voltage going UP !(???)
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Normal it work: about 260 kHZ signal from relaxation oscillator separated and formed by second gate. Sawtooth signal going on the 3rd gate and otput 3rd gate forming square (from possitive peak of coil) with over 90% plus duty. Last gate reverse phase signal from 3rd gate we have square with less than 10% duty. At the end RC fiter get the average voltage from square vawe of 4th gate and precission is here 10mV/1uH. Voltage level is proportional to inductance. Range from 500 nH to 50uH
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THANKS TO GREAT hurz HELP who helped build the schmitt trigger and explaining the rules he wrote:
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Schmitt trigger gate model surrounded by switches 3 gates and some resistors to emulate a single 74HC14 gate
Hysteresis is about 1V like the original on according to Philips spec. This is to any timing/frequency calculation very important.
Input resistance is 10MOhm which should be for most cases high enough.
Since EC and its propagation delay, keep an eye on delay parameter to get it right for your simulation speed!
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