Related MCP servers: scope and boundaries¶
mcp-ltspice-qucs is one piece of a larger ecosystem of
engineering-domain MCP servers. This document tells an LLM agent (or a
human reader) which tool to reach for when a question spans more
than one domain, and where this suite explicitly does not
duplicate work that another MCP already covers.
Some of the sister MCPs referenced below are public (linked); others are described by capability because the implementations are not yet public. The scope guidance applies regardless: don't reach for this suite to solve a problem that's outside its layer.
What this MCP suite covers¶
- Filter synthesis: LC ladders (Butterworth / Chebyshev / elliptic), active filters (Sallen-Key / MFB), transmission-zero placement, real- vendor part substitution, optimisation, Monte Carlo yield.
- Distributed-element synthesis (closed-form): microstrip lines, branch-line / rat-race / Lange / coupled-line couplers, Richards-Kuroda lumped-to-distributed conversion.
- SPICE simulation: LTspice (Wine) or ngspice;
.rawparser; S-parameter extraction. - SMPS sizing: buck / boost / LDO; type-II compensator; Bode + phase-margin analysis.
- SMPS EMC pre-compliance (circuit-level): Pi LC output filter, DM input filter with Middlebrook check, conducted-emissions prediction with CISPR 22/32 limit overlay, RC snubber, common-mode choke selection.
- Coexistence: multi-radio harmonic-victim lookup, desense matrix.
- Component catalogues: op-amp / MOSFET / BJT / diode / voltage reference datasheet metadata.
- Digital / mixed-signal helpers: setup/hold timing, propagation delay, digital-to-analog crosstalk, supply-noise injection.
What this MCP suite explicitly does not cover¶
| Domain | Reach for | Why we don't duplicate |
|---|---|---|
| Antenna design / radiation patterns | A NEC2 method-of-moments antenna MCP (closed-form + dipole, vertical, loop, Yagi, inverted-V) and/or an FDTD full-wave EM MCP (patch, monopole, helix, horn, microstrip antenna) | Antenna synthesis and radiation simulation are their own domain. We deliberately stop at the antenna port. |
| PCB-level EMC / SI / PI (impedance from layout, decoupling, return paths, crosstalk from geometry, stackup, copper pours, vias) | A PCB-layout-aware EMC MCP | We're circuit-level (schematic in, S-params / yield out). Layout-aware EMC is board-level (layout in, EMC margin out). Two sides of "I have a circuit, now lay it out". |
| Regulatory standards lookup (CISPR / FCC Part 15 / Part 18 / Part 95 / ETSI / 3GPP / IEC 61000 / ISO 11452 / CISPR 25) | [mcp-emc-regulations] |
Authoritative regulatory tables and cross-reference. Our band-list / CISPR-limit tools are filter-design helpers (subsets used internally by lookup_harmonic_victims etc.). Not the canonical reference. |
| RF testing of physical hardware (BLE / WiFi / HaLow on a real DUT) | A hardware-DUT RF test MCP | We're pre-silicon / pre-board simulation. Hardware testing drives an actual device. |
| Physical-layer SDR captures | An SDR capture MCP | Same. We're at design-time, SDR capture is at runtime. |
| 3D CAD / mechanical | [mcp-blender] |
Out of scope. |
| Drawio engineering diagrams | [drawio-engineering-mcp] |
Out of scope. |
Specific tool overlaps and recommendations¶
These tools in mcp-ltspice-qucs overlap functionally with capabilities
that exist elsewhere. We keep them because they integrate tightly with
our filter / SMPS workflows, but if you only need the standalone
capability, prefer the canonical source.
Microstrip impedance (analysis direction)¶
| This MCP | Canonical alternative | When to use which |
|---|---|---|
mcp-qucs-s.synthesize_microstrip_line (Z₀ → W, L) |
: (synthesis is unique) | This MCP: synthesis is unique |
mcp-qucs-s.analyze_microstrip_tool (W → Z₀) |
a PCB-layout-aware EMC MCP | Prefer the layout-aware tool for analysis if one is available. It integrates with the wider PCB workflow (CPW, stripline, differential, eye-diagram). Use ours when you're already mid-Richards-Kuroda flow. |
Frequency-band data (regulatory tables)¶
| This MCP (filter-design helper subset) | Canonical regulatory source |
|---|---|
list_lte_bands_tool |
mcp-emc-regulations.lte_bands_list |
list_5gnr_bands_tool |
mcp-emc-regulations.nr_bands_list |
list_ism_bands_tool |
mcp-emc-regulations.ism_bands_list |
list_gnss_bands_tool |
(broader regulatory in mcp-emc-regulations) |
list_fcc_restricted_bands_tool |
mcp-emc-regulations.fcc_restricted_bands_list |
For day-to-day filter design, the in-suite versions are convenient
because they feed directly into lookup_harmonic_victims and
check_coex_matrix. For authoritative regulatory queries (medical,
automotive, certification matrix, market requirements), use
[mcp-emc-regulations].
The reverse-lookup tool lookup_band_by_freq_tool (returns all band
categories matching a single frequency) is unique to this MCP.
HaLow channel grids¶
list_halow_channels_tool is unique to this MCP. No external
server (that we're aware of) carries the IEEE 802.11ah regional
channel sets (EU 863–870, US/AU/NZ 902–928, JP 916.5–927.5, KR
917.5–923.5, CN 755–787, etc.).
Conducted-emissions prediction¶
| This MCP | Canonical alternative | When to use which |
|---|---|---|
mcp-rf-analysis.predict_conducted_emissions |
a PCB-layout-aware EMC MCP | This MCP: post-circuit (you have an SMPS schematic; predict emissions from line-current spectrum + filter S-params). Layout-aware tool: pre-circuit / topology-level (you have an SMPS topology spec; predict emissions from switching parameters). |
mcp-ltspice.predict_conducted_emissions (in power.emc) |
a PCB-layout-aware EMC MCP | This MCP: trapezoidal-waveform harmonic decomposition with CISPR 22/32 limit overlay; couples directly into design_pi_output_filter / design_dm_input_filter results. Layout-aware tool: layout-aware analysis once the PCB exists. |
The in-suite tools couple cleanly to filter design (you predict emissions, then size the filter, then re-predict). A layout-aware tool takes over once the layout exists.
CISPR / FCC limit lookup (no overlap with bigger picture)¶
mcp-rf-analysis.cispr_limit_at and fcc_part15_radiated_limit_at
return narrow Class A/B values used inline by the filter / EMC
prediction tools. For the broader regulatory matrix
(certification timelines, market-by-market test requirements,
medical / automotive / IEC 61000 immunity levels), use
[mcp-emc-regulations].
Decision flow for an LLM agent¶
Are you designing an antenna?
→ use a NEC2-based or FDTD antenna MCP
Are you analysing an existing PCB layout?
→ use a PCB-layout-aware EMC MCP
Are you looking up a regulatory limit / certification requirement?
→ use mcp-emc-regulations
Are you designing a filter, SMPS, EMI filter, or coupler from spec?
Are you predicting conducted emissions from a switching converter?
Are you computing harmonic landings into LTE / GNSS bands?
Are you running an LTspice / ngspice / Qucs-S simulation?
→ use this MCP suite (mcp-ltspice / mcp-rf-analysis / mcp-qucs-s)
Are you testing a physical DUT or capturing IQ samples?
→ use a hardware-DUT RF test MCP / an SDR capture MCP
Cross-MCP workflow examples¶
Designing a DC/DC power rail to pass FCC Part 15 conducted emissions¶
mcp-ltspice.design_buck→ first-cut L, Coutmcp-ltspice.design_pi_output_filter→ ripple suppressionmcp-ltspice.design_dm_input_filter→ input EMI filter (Middlebrook stable)mcp-ltspice.design_cm_choke→ CM choke selectionmcp-ltspice.predict_conducted_emissions→ CISPR margin per harmonic- (optional) a PCB-layout-aware EMC tool → board-level cross-check after layout
mcp-emc-regulations.fcc_part15_limit→ confirm exact regulatory limitmcp-emc-regulations.test_plan_generator→ certification test plan
Designing a 2.4 GHz front-end with antenna + matching network + filter¶
- (antenna MCP: NEC2 closed-form or FDTD full-wave) → antenna design + radiation pattern
mcp-qucs-s.synthesize_coupler→ branch-line splitter if neededmcp-ltspice.synthesize_lc_filter(Chebyshev BPF) → harmonic / image filtermcp-rf-analysis.cascade_networks→ composite S-parametersmcp-rf-analysis.check_passband_compliance→ passband / RL marginsmcp-rf-analysis.lookup_harmonic_victims→ coex check vs LTE / GNSS- (PCB-layout-aware tool) → trace impedance for the matching network, return-current paths, ground stitching