45
OSD3358-SM-RED
– User Guide
Rev. 1.0 9/19/2017
Octavo Systems LLC
Copyright 2017
Figure 43: OSD3358-SM-RED power button
The OSD335x-SM-RED board also provides a power button S2 connected to the PMIC_PB_IN
(active low push button input of PMIC). PMIC_PB_IN has the following functions:
•
The PMIC will be powered up from OFF or SLEEP mode upon detecting a falling edge
on PWR_BUT signal (hold the power button, S2 down).
•
PMIC is power cycled/reset when PWR_BUT (Switch S2) is held low for more than 8 s.
All rails will be shut down by the sequencer and all register values are reset to their
default values. Rails not controlled by the sequencer are shut down immediately. After 1
sec of RESET state, the board powers up again.
•
If the PMIC_IN_PB_IN pin is kept low for an extended amount of time, the device will
continue to cycle between ACTIVE and RESET state, entering RESET every 8 seconds.
Figure 43 also shows a 2 pin header J2. Pin 1 of the jumper is connected to PMIC_NRESET
and pin 2 is connected to GND. The PMIC can be put in reset state by using a jumper to
connect the 2 pins of the header. The PMIC will remain in reset until the PMIC_NRESET input is
released from the pull down to GND and for a minimum of 1 sec.
NOTE:
Holding the power button low for 8 seconds on some boards will power off the
system instead of power cycling it depending on current draw.
