XRP7725 Datasheet, PDF (27/34 Pages) Exar Corporation – Power Management System

XRP7725
Intel Node Manager Compatible Programmable
Power Management System
• Order – position of a channel to come-up
within the group
• Wait PGOOD? – selecting this option for
a channel means the next channel in the
order will not start ramping-up until this
channel reaches the target level and its
Power Good flag is asserted
• Delay – an additional time delay a user
can specify to postpone a channel start-up
with respect to the previous channel in the
order. The delay is expressed in
milliseconds with a range of 0msec to
255msec
Shut-down
INSTANTANEOUS CURRENT MONITORING
XRP7725 will capture V_IL readings every
1msec on all channels until a user defined
sample threshold is reached. Then, the sum is
latched into a separate register to be read
from an I²C command.
For each channel within a group a user can
specify
the
following
shut-down
characteristics:
• Ramp Rate – expressed in milliseconds
per volt. It does not apply to LDO3.3
• Order – position of a channel to come-
down within the group
• Wait Stop Thresh? – selecting this
option for a channel means the next
channel in the order will not start
ramping-down until this channel reaches
the Stop Threshold level. The stop
threshold level is fixed at 600mV
• Delay – additional time delay a user can
specify to postpone a channel shut-down
with respect to the previous channel in the
order. The delay is expressed in
milliseconds with a range of 0msec to
255msec
MONITORING V_CC AND TEMPERATURE
Through I²C commands, the host can read
back the voltage applied to the V_CC pin and
the die temperature respectively. The V_CC
read back resolution is 200mV per LSB; the
die temperature read back resolution is 5C°
per LSB. For more on I²C commands please
refer to ANP-38.
The sample size is selected in Power Architect
5.1 (PA 5.1). The recommended maximum
sample size is 512. Going over this limit could
potentially cause overflow. In certain designs
it would be possible to increase sample size
above this limit without problems, but this will
depend on the design parameters. If there is
such a need please contact Exar
representatives who will determine if your
design is suitable.
© 2014 Exar Corporation
27/34
Rev. 1.0.0