Modern x360 system design uses two hall sensors for clamshell(CS) & x360 tablet detection. This design leaves a
vulnerability to users if they are unintentionally approaching CS hall sensor with some magnetic components, touch pen
for this example, users might experience panel off or flicker when they are operating system in tablet mode. Problem to
this is due to panel backlight controlled by CS hall sensor directly as illustrated in Fig. 1 below. Fig. 2 shows the circuitry
on current x360 hall sensors design and highlighted in yellow for control pins: LID_SW_3 for CS lid output and
BLON_CON for panel backlight control.
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INC, HP, "AVOID LID SWITCH (HALL SENSOR) TIGGERED BY X360 TABLET MODE CAUSING PANEL OFF", Technical Disclosure Commons, (September 12, 2018)