View source for Mermaid:Mechanic L1 Pro Failure Sequence

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sequenceDiagram
    participant User
    participant PowerButton
    participant QX9920
    participant Q1
    participant LED

    User->>PowerButton: Turns lamp ON directly
    Note over PowerButton,QX9920: Timer bypassed -<br/>no auto cutoff<br/>scheduled
    PowerButton->>QX9920: VIN applied, EN held<br/>high continuously
    QX9920->>Q1: DRV switches gate<br/>at full duty
    Q1->>LED: Sustained drive<br/>current, no rest

    loop Extended runtime,<br/>no shutoff
        Q1->>Q1: Conduction + switching<br/>losses generate heat
        Note over Q1: Heat dissipation<br/>can't keep pace
    end

    Note over Q1: Junction temp exceeds<br/>rated max
    Q1-->>Q1: Thermal failure -<br/>commonly fails shorted D-S
    Q1->>LED: Uncontrolled current -<br/>CS feedback no longer limits
    Note over LED: LED experiences<br/>overcurrent stress