String Calculator

How many LEDs can one string drive?

Choose a part, power supply, series/parallel layout and wire to estimate max LED count, real power and string refresh rate — and check whether wire drop or signal distortion becomes the bottleneck.

Choose a part

Series

Part

Power supply

Voltage (V)

PSU rated current (A)

String structure

Series groups S

Parallel P (0 = auto max)

Feed

Bead spacing (cm) wire length between adjacent beads

Lead length (m)

Wire

Content and targets

Minimum refresh rate (Hz, 0 = none)

Advanced assumptions

Recommended Configuration

Item	Value	Notes

Last-bead voltage vs LED count

This is an engineering estimate: copper resistance at 20 °C, constant-current beads, diagonal feed per series-parallel group. Refresh rate is derived from each model’s data rate and calibrated against measurements (e.g. P9864S ≈ 25 Hz at 100 LEDs). Signal distortion uses a distributed-RC edge time and ignores wire-inductance ringing and crosstalk. Use the official datasheet and measurements for production designs.
Not included (specs unpublished or not two-wire carrier): P9865G, P9868I, P9835, P9032A, P9165A, P9825, P9779, P9828x — please contact sales.