Lab Tests

Status: Draft Project: Enigma-NG Author: Izzyonstage & GitHub Copilot Version: v.0.1.0 Associated Hardware Revision: Rev A Last Updated: 2026-04-26

Overview

This document tracks all lab-bench tests required to confirm or finalise design parameters that cannot be resolved without physical prototypes. Tests are assigned IDs (LT-NNN) and cross-referenced from relevant design and software specification documents.

Tests must be executed on Rev A prototype hardware before those parameter values are considered finalised. Results should be recorded in this document and the relevant design files updated where necessary.

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Lab Test Register

ID	Title	Description	Purpose	Expected Result	Status
LT-001	FDC2114 IDRIVE Baseline Calibration	Apply baseline DRIVE_CURRENT_CHx = 0x7C00 (IDRIVE = 0b01111) to a populated Rotor board. Using an oscilloscope probe at the INxA/INxB pads, measure the peak-to-peak sensor drive voltage across the LC tank for each active channel. Adjust IDRIVE register field upward or downward until the measured drive is within the 1.2-1.8 Vpk target range documented in TI FDC2114 datasheet §8.4.3. Record the final IDRIVE value and update design/Software/CPLD_Logic/Rotor_Logic.md §2.1.	Confirm the baseline drive current produces adequate LC tank excitation without exceeding maximum sensor drive. Too low → poor sensitivity; too high → saturation or IC damage.	Sensor drive within 1.2-1.8 Vpk on all active channels at IDRIVE = 0b01111, or a revised IDRIVE value identified and documented.	Pending prototype
LT-002	fSENSOR Resonant Frequency Validation	With the LC tank assembled (18 µH + 33 pF in parallel between INxA/INxB), use a network analyser or FDC2114 data register read to confirm the measured resonant frequency of each channel. Verify the measured fRES is below 80% of the selected inductor's self-resonant frequency (SRF). Record measured fRES per channel and per board variant (N=26 and N=64 builds). Update design/Electronics/Rotor/Design_Spec.md §2.1 with final measured values.	Confirm the selected 18 µH part is suitable for ~6.5 MHz tank operation and that fRES < 0.8 x SRF to ensure valid inductance at operating frequency.	Measured fRES per channel ≈ 6.5 MHz (within ±10%), and fRES < 0.8 x inductor SRF for all channels on both board variants.	Pending prototype