noise_integral
Integrate a noise spectral density trace (V/√Hz or A/√Hz) to total RMS noise over a specified frequency band from LTspice or ngspice .noise results, reporting the integrated band and sample count.
Instructions
Integrate a .noise spectral density to a total RMS noise over a band. SPICE stores amplitude density (V/√Hz or A/√Hz) for both LTspice and ngspice, so total = sqrt(∫ density² df) — the same value LTspice shows when you Ctrl-click a V(onoise) label. Reports the band actually integrated and the sample count. Noise figure / SNR are left to you (they need the source resistance and a reference level).
Input Schema
| Name | Required | Description | Default |
|---|---|---|---|
| step | No | Step index for .step sweeps | |
| f_end | No | Band end (e.g. '20k'); default = sweep end. | |
| format | No | 'json' or 'text' | |
| job_id | No | Integrate a run of a completed sweep/MC (or single) job instead of a raw_file path; pair with ``run_index``. | |
| signal | No | Noise-density trace to integrate: 'V(onoise)'/'V(inoise)' (LTspice) or 'onoise_spectrum'/'inoise_spectrum' (ngspice). Default integrates the output noise (onoise). | |
| f_start | No | Band start in SPICE notation (e.g. '20'); default = sweep start. | |
| raw_file | No | Path to .raw .noise result. Pass this OR ``job_id`` (a job run), not both. | |
| run_index | No | 0-based run to read when ``job_id`` is given (default 0). |
Output Schema
| Name | Required | Description | Default |
|---|---|---|---|
| unit | No | ||
| signal | No | ||
| n_points | No | ||
| warnings | No | ||
| total_rms | No | ||
| f_end_used | No | ||
| density_unit | No | ||
| f_start_used | No |