📉 PDN Impedance Calculator

Optimize decoupling capacitor network & PCB plane capacitance for target impedance

Complies with IPC-2221 / TI PDN guidelines
Maximum allowable PDN impedance at target frequency
Typical switching frequency or critical harmonic
Comma-separated list (e.g., 47uF, 4.7uF, 0.1uF). First value used for parallel count estimation.
Equivalent series inductance (0603 ~ 800pF, 0402 ~ 400pH)
Equivalent series resistance (ceramic: 1-20mΩ)
📖 Model: Single capacitor impedance |Z| = √(ESR² + (2πf·ESL - 1/(2πf·C))²). Parallel n identical caps reduce ESL and ESR by n, increase C by n. Plane capacitance C = ε₀·εr·A/d. The total PDN impedance is the parallel combination of all capacitors and plane.
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