I have a timing circuit application that depends on the intervals with duration determined by an RC circuit. When a capacitor is [dis]charged through such a circuit, a voltage level across the capacitor between the levels at the beginning and the destination is visited only once for a single time interval. Can you explain why?
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4\$\begingroup\$ A very warm welcome to the site. With so little detail in it, you can see that this reads like a homework question. People will help you take the next step if your question shows you've already done as much as you possibly could on your own - which yours doesn't, I'm afraid. Please edit your question and greatly improve it. Show your own work and own findings in considerable detail with any schematic. The schematic tool here is easy to use. The better the quality of your question, the better the quality of the answers it will attract. Again, welcome. \$\endgroup\$– TonyMOct 20, 2020 at 7:57
1 Answer
If that "timing interval" places a fixed voltage across the charging R+C circuit, with the R in series to set current by { (Vin - Vcapacitor) / Rvalue }, then the capacitor voltage rises rapidly at first (the slewrate is exactly {Vin/ (R * C)} ) but the charging rate exponentially becomes slower as the Vcapacitor gets closer and closer to the final value.