Device physicsMVP
Interconnect RC delay
First-order RC delay of an interconnect: τ = R·C, with a 50% delay of about 0.69·R·C.
Inputs
Result
Enter values and calculate to see the result.
Interpretation
Enter the interconnect resistance and capacitance.
Formula
τ = R · C ; t₅₀ ≈ 0.69 · R · C
Lumped single-stage RC.
Variables
| Symbol | Variable | Unit |
|---|---|---|
| τ | Time constant | s (shown as ps) |
| R | Resistance | Ω |
| C | Capacitance | F |
| t₅₀ | 50% propagation delay | s |
Assumptions & validity
This tool assumes:
- Single lumped R and C (one stage).
- A distributed wire differs (Elmore ≈ 0.38·R·C for a uniform line); first-order estimate only.
Worked example
R = 1 kΩ, C = 1 pF.
τ = 1 ns; 50% delay ≈ 0.69 ns