neazoi
Advanced Member level 6
Hi I am thinking of a timer that uses an R/C to drive the base of a BJT, so as to create a 5 minutes delay.
How accurate this RC can be made when placed in a clock circuit with 5 minutes step (i.e clock minutes needle changes every 5 minutes)
I am thinking of using an NP0 capacitor (so it has to be small) and a very large 0.1ppm resistor. How accurate can it be in a 24 hour period?
Or another example, according to this calculator for example https://www.digikey.com/en/resources/conversion-calculators/conversion-calculator-time-constant a 50nf and 20Mohms will give a 1pps. How accurate this can be if using 0.1ppm resistors and NP0 capacitors?
How accurate this RC can be made when placed in a clock circuit with 5 minutes step (i.e clock minutes needle changes every 5 minutes)
I am thinking of using an NP0 capacitor (so it has to be small) and a very large 0.1ppm resistor. How accurate can it be in a 24 hour period?
Or another example, according to this calculator for example https://www.digikey.com/en/resources/conversion-calculators/conversion-calculator-time-constant a 50nf and 20Mohms will give a 1pps. How accurate this can be if using 0.1ppm resistors and NP0 capacitors?
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