XRP7725 Datasheet, PDF (26/34 Pages) Exar Corporation – Power Management System

XRP7725
Intel Node Manager Compatible Programmable
Power Management System
commands with resolution of 2.5mV, 5mV
and 10mV depending on the target voltage
range (in PWM mode only).
For more information on I²C commands
please refer to ANP-38 or contact Exar or
your local Exar representative.
POWER SEQUENCING
All four channels and LDO3.3 can be grouped
together and will start-up and shut-down in a
user defined sequence.
Selecting none means channel(s) will not be
assigned to any group and therefore will be
controlled independently.
Group Selection
There are three groups:
• Group 0 – is controlled by the chip
ENABLE or an I²C command. Channels
assigned to this group will come up with
the ENABLE signal being high (plus
additional delay needed to load
configuration from Flash to run-time
registers), and will go down with the
ENABLE signal being low. The control can
always be overridden with an I²C
command
Since it is recommended to leave the
ENABLE pin floating in the applications
when V_CC = LDO5 = 4.75V to 5.5V, please
contact Exar for how to configure the
channels to come up at the power up in
this scenario
• Group 1 – can be controlled by any
GPIO/PSIO or I²C command. Channels
assigned to this group will start-up or
shut-down following transitions of a signal
applied to the GPIO/PSIO set to control
the group. The control can always be
overridden with an I²C command
• Group 2 – can be controlled by any
GPIO/PSIO or I²C command. Channels
assigned to this group will start-up or
shut-down following transitions of a signal
applied to the GPIO/PSIO set to control
the group. The control can always be
overridden with an I²C command
Start-up
© 2014 Exar Corporation
For each channel within a group, a user can
specify the following start-up characteristics:
• Ramp Rate – expressed in milliseconds
per volt. It does not apply to LDO3.3
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