Toradex Verdin - Running to No VCC (Force Off)

Verdin Carrier Board Design Guide
Preliminary – Subject to Change
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3.3.7 “Running” to “No VCC” (force off)
Figure 54: “Running” to “No VCC” (force off) Power Sequence
The force OFF sequence is initiated by pressing the power button for more than 5 seconds. The
difference between the force OFF and a regular shutdown sequence is that the force OFF starts
without interaction with the operating system. This means, the operating system cannot prevent
corruptions by saving temporary data, flushing buffers, closing files or disconnecting services. On
the other hand, with force OFF the system can be shut down independently of the state of the
operating system or other software running on the module.
The force OFF sequence is identical to the shutdown sequence. This means that the PMIC first sets
the reset signals low and then removes the power rails in the required order. After all rails have
been removed, there is a delay after which the CTRL_FORCE_OFF_MOCI# goes low.
VCC_BACKUP
VCC
Early Module Rails
PWR_1V8_MOCI#
Carrier Board rails
Later Module Rails
Module Peripherals
CB Sleep Peripherals
CTRL_PWR_BTN_MICO#
CTRL_RESET_MICO#
CTRL_PWR_EN_MOCI
CTRL_SLEEP_MOCI#
CTRL_FORCE_OFF_MOCI#
CTRL_WAKE1_MICO#
SoC RESET
CTRL_RESET_MOCI#