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== Reset scheme and control signals ==
The following picture shows the simplified block diagram of reset scheme and voltage monitoring.
[[File:MITO 8MMito8MMini-reset-scheme.png | 800px500x500px]]
=== NVCC_VSNVS NVCC_VSNVS_1V8 ===Some signals that are related to reset circuitry are pulled-up to NVCC_VSNVS (aka 3.3VIN)NVCC_VSNVS_1V8.
Hence '''it is recommended that system designer takes into account these factors in order to properly manage these signals at carrier board level'''.
=== EXT_RESET ===
EXT_RESET is internally pulled-up with a 90kΩ to NVCC_VSNVS. Connect EXT_RESET signal to GND (for example with a button or an open-collector circuit) causes the internal supervisor IC to assert its RESETn output.
This will power down the VDD_SOC_0V9 and make PMIC_ON pulled low by PG (Power Good) of VDD_SOC_0V9 regulator.
Since PMIC_ON serves as the enable signal of PMIC and other discrete power supply chips, all the power supplies except for the SNVS domain will be OFF.
The RESETn will keep asserted for 270 ms after EXT_RESET is released, thus providing enough time for the power supplies to be completely powered down. During this time, the POR_B driven by the PMIC will also keep asserted (low).
After RESETn is released, the power supplies will start to ramp up in defined sequence. When all the power supplies have reached their operating voltages, POR_B will be de-asserted, and the CPU may begin booting from reset.
=== CPU_PORn ===
PMIC can assert this active-low signal and it is internally pulled-up with a 100kΩ to NVCC_VSNVS_1V8.
PMIC can assert this active-low signal. Other internal IC, such as ethernet PHY or boot memory devices, could be connected to this signal. This guarantees it is in a known state when reset signal is released.=== PMIC_PWRON ===PMIC_PWRON is internally pulled-up with a 100kΩ to VIN and has a capacitor of 10nF to GND. This input signal is connected directly to the PWRON input of the PMIC.
=== CPU_ONOFF ===
CPU_ONOFF is internally pulled-up with a 100kΩ to NVCC_VSNVSNVCC_VSNVS_1V8. This input signal is connected directly to the ONOFF input of the CPU.
=== BOARD_PGOOD ===
