@priyadarshini_m
Hello,
From i.MX 8M Mini LPDDR4 EVKB Board Hardware User's Guide( Rev. 0, February 18, 2021):
2.19 (User interface buttons)
There are two user interface buttons on the EVKB board.
2.19.1 [Power button (SW901)]
The i.MX 8M Mini Applications Processor supports the use of a button input signal to request main SoC power state changes (i.e. ON or OFF) from the PMU.
The ON/OFF button can be used for debounce, OFF-to-ON time, and max timeout. Debounce is used to generate the power-off interrupt. In the ON state, if the ON/OFF button is held longer than the debounce time, the power-off interrupt is generated. In the OFF state, if the ON/OFF button is held longer than the OFF-to-ON time, the state will transit from OFF to ON. Max timeout can also be the time for requesting physical power down after the ON/OFF button has been held for the defined time.
2.19.2 [Reset button (SW902)]
The RESET button (SW902) is directly connected to the PMIC PCA9450A. Holding the RESET button will force to reset the PMIC power outputs except NVCC_SNVS_1V8 and VDD_SNVS_0V8 on the EVKB board. The i.MX 8M Mini applications processor will be immediately turned off and reinitiate a boot cycle from the OFF state.
< https://www.nxp.com/docs/en/user-guide/IMX8MMEVKBHUG.pdf >
According to Hardware Development Guide for the i.MX8Mm:
For portable applications, the ONOFF pin may be connected to an ON/OFF SPST push-button switch to ground. An external pull-up resistor is required on this pin.
A brief connection to GND in OFF mode causes the internal power management state machine to change state to ON. In ON mode, a brief connection to GND generates an interrupt (intended to initiate a software-controllable power-down). The connection to GND for approximate 5 seconds or more causes a forced OFF.
< https://www.nxp.com/docs/en/user-guide/IMX8MMHDG.pdf >
Regards,
Yuri.