Auto Power-On¶
To ensure the LattePanda Mu compute module boots up automatically when power is applied, an external hardware circuit is required on the carrier board.
- ✅ Hardware-based implementation is strongly recommended for reliability. This ensures consistent boot behavior even after abnormal power loss or rapid power cycling.
- ❌ Not Recommended: Relying solely on BIOS menu settings like "Restore AC Power Loss".
Reference Circuit¶
Circuit Principle¶
The purpose of this circuit is to electrically simulate the physical action of pressing the power button.
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Initialization: The circuit activates immediately when the carrier board receives power.
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Action: It pulls the
PWR_BTN#(Power Button) signal LOW for a specific duration (simulating a "Press"), triggering the compute module's boot sequence. -
Release: After the delay, it releases
PWR_BTN#back to HIGH (simulating a "Release").
JP1 is a jumper. When JP1 is ON, the automatic power-on function is enabled.
Power Requirement¶
The power supply for the auto power-on circuit MUST be 3.3V Standby. That is, this 3.3V power supply must be active as soon as the carrier board is plugged in the main power.
