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THE FEUTEX TOOLKIT

RC Threshold Crossing

Calculate charging time to a specified comparator threshold.

Electronics workspace● Runs in your browser
01 Your input
02 Your result
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Formulat=−RC ln[(Vs−Vth)/(Vs−V0)]
Sources and model references

Worked example

Inputs

Resistance
1000 ohm
Capacitance
0.001 F
Initial voltage
0 V
Source voltage
10 V
Threshold
5 V

Expected results

Threshold time
0.6931471806 s
Slope at threshold
5 V/s

Load the example in the workspace to reproduce these results. Display rounding does not change the underlying calculation.

How to use this tool

  1. Enter the labeled inputs in the indicated units.
  2. Calculate and compare every output against the stated model assumptions.

Try this example

{
  "r": 1000,
  "c": 0.001,
  "initial": 0,
  "final": 10,
  "threshold": 5
}

Accuracy and scope

Single passive RC, ideal voltage step, no leakage or loading. Simplified analytical model; not a design recommendation or safety certification.

Is my data uploaded?

This tool runs locally in your browser. Input and output are not sent to a processing server. Copy or download your result before leaving the page.