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  (title_block
    (title "Power Sequence")
    (date "2026-09-06")
    (rev "A draft")
    (company "Engineered Lighting")
    (comment 1 "ENGINEERING DRAFT - see release status before fabrication"))
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  (text "POWER SEQUENCE"
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  (text "SUPPLY QUALIFICATION / HARDWARE LIGHTING INHIBIT"
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  (text "U18 monitors +3V3: 3.07 V nominal falling threshold.\nCT intentionally open: 12-28 ms reset release delay.\nR42 limits discharge from existing MCU_EN capacitor C1.\nMCU_EN pullup R1, capacitor C1 and manual S1 are on controller."
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  (text "READY also feeds USB R41/R39; independent of ARM.\nPrototype timing and 0<V3V3<1.65 V behavior require measurement.\nAfter reset: initialize outputs OFF, verify PCA state, require fresh enable."
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