| Circuit Diagram Completeness | Provide readable schematics covering power supply, main board, LED backlight, audio, interfaces, protection circuits, component references, and test points. | Sample PDF or CAD files, revision history, circuit block diagram, BOM cross-reference, and controlled-document procedure. | 20% | No critical block or reference-designation gaps |
| Technical Accuracy | Component values, pin assignments, polarity marks, connector definitions, voltage rails, and signal names must match the supplied hardware or reference sample. | Independent schematic review, continuity checks, voltage-rail comparison, and sample-board inspection. | 18% | Zero unresolved safety-critical errors |
| Reverse-Engineering and Test Capability | Maintain suitable tools for measurement and documentation, including a digital multimeter, oscilloscope, programmable power supply, electronic load, and continuity tester. | Equipment list, calibration records, test reports, engineering work instructions, and a live sample demonstration. | 15% | Current calibration records for measurement equipment |
| Safety and Compliance Awareness | Design documentation should identify hazardous voltage areas, protective earth, fuses, insulation barriers, creepage, clearance, and applicable product-safety requirements. | Risk assessment, insulation notes, safety-component list, and evidence of alignment with IEC 62368-1 where applicable. | 12% | All safety-critical items clearly identified |
| Document Control and Revision Management | Every file should include document number, revision, issue date, author or reviewer, change description, and approval status. | Controlled-document sample, revision log, file-naming rules, and change-approval workflow. | 10% | Traceable revision history for every deliverable |
| Confidentiality and Intellectual Property | Use a signed confidentiality agreement, define ownership of drawings and derivative work, and restrict access to project files. | Executed NDA, intellectual-property clauses, access-control policy, and data-retention procedure. | 10% | Signed agreement before technical disclosure |
| Quality Management | Use documented inspection, corrective-action, nonconformance, and customer-complaint processes. ISO 9001 certification is a useful supporting indicator. | Valid certificate where available, internal quality procedures, corrective-action records, and audit results. | 6% | Documented corrective action with closure evidence |
| Sample and Pilot Testing | Complete a small paid trial before a long-term agreement, using a defined acceptance checklist and one controlled sample revision. | Pilot schematic, test report, issue log, response records, and final corrected revision. | 5% | All major findings closed before approval |
| Delivery and Communication | Agree on milestones for requirements, preliminary drawing, review version, final files, and engineering-change response. | Project schedule, named technical contact, response-time commitment, and milestone records. | 4% | Milestones and escalation path documented |