Arc Skills / Interfaces
Review an electrical interface specification
One passing logic threshold does not prove an entire link is compatible. Arc Skills takes pin maps and endpoint ratings and returns a path review that separates supported checks from missing evidence.
Use this skill
Use Arc Skills to review my electrical Interface between two configured Systems.
Inputs:
- Connector and pin definitions with revision and viewing orientation
- Guaranteed source/output and receiver/input operating ranges, rails and modes
- Return, isolation, fault, transient, inrush and harness evidence where applicable
Return a pin/path review with each supported calculation, open check and owner action. Keep a passing local threshold comparison separate from whole-link compatibility.What you provide and what you get
| What you have | How it is used | What you get |
|---|---|---|
| Connector and harness definitions | Maps actual source and load pins | Pin/path trace |
| Electrical ratings | Compares guarantees against acceptance thresholds | Supported envelope calculations |
| Ground and fault details | Tests reference and protection assumptions | Open checks and owner actions |
Logic-high threshold passes one check
Illustrative engineering example.
In this fictional digital link, the controller guarantees at least 3.3 V high at its output pin and the receiver recognizes high at 2.0 V or above at its input pin. The common-reference connection and permissible receiver input overshoot are absent from the supplied snippets.
Controller J1-3 → receiver J2-7: data high ≥3.3 V guaranteed at controller pin
Receiver VIH threshold: 2.0 V at receiver pin
Return pin and allowable overshoot: TBD| Path or check | Source claim | Load need | Finding |
|---|---|---|---|
| Data-high voltage | Guaranteed high ≥3.3 V at source pin | VIH threshold 2.0 V at receiver pin | Source-pin-to-threshold difference ≥1.3 V; cable/return losses TBD |
| Common return | Return path not documented | Shared reference needed for threshold meaning | Open; map ground pins and isolation |
| Input overshoot | Transient output not supplied | Maximum input transient not supplied | Open; cannot assess transient compatibility |
| Drive current | Output capability not supplied | Input current not supplied | Open; request load/drive envelope |
The 1.3 V difference is a source-pin-to-receiver-threshold comparison under the stated values, not a verified input-pin voltage. Cable drop, ground offset and noise can consume that difference; none is quantified here. The receiver input must still exceed 2.0 V under worst relevant conditions. A receiver threshold is meaningful only relative to a defined return, so missing grounding prevents a whole-link pass.
Connector pin numbering also depends on whether each drawing is viewed from the mating face or wire side. The review should fix that orientation before a build or continuity check. A data-high match must not mask unknown overshoot, drive current, protection or startup states.
Trace every electrical path
- Pin both endpoint revisions and connector viewpoints.
- Trace source pin, harness, load pin and return for each power or signal path.
- Compare guaranteed operating envelopes, thresholds and fault limits under matching conditions.
- Report local passes and unknowns separately, with the exact source needed to close each.
Questions about this task
Does 3.3 V above 2.0 V prove a working link?
Only the stated static high-threshold comparison. Ground reference, noise, timing, current and transients remain separate checks.
Can absolute-maximum ratings replace normal operating limits?
No. Survival limits are not operating guarantees and should not be used as ordinary compatibility bounds.
Sources and further reading
- NASA Systems Engineering Handbook: product realization: Interface definition, integration sequence and verification context.
- NASA Systems Engineering Handbook: system design processes: Stakeholder expectations, logical decomposition, functional allocation and design decisions.