Technical Product Specification

Power Sub-System Intel
®
Server System H2000WP Family TPS
AC Input
Vout
PWOK
12Vsb
PSON
T
sb_on_delay
T
AC_on_delay
T
pwok_on
T
vout_holdup
T
pwok_holdup
T
pson_on_delay
T
sb_on_delay
T
pwok_on
T
pwok_off
T
pwok_off
T
pson_pwok
T
pwok_low
T
sb_vout
AC turn on/off cycle
PSON turn on/off cycle
T
5Vsb _ holdup
Figure 15. Turn On/Off Timing (Power Supply Signals)
3.4 Power Supply Cold Redundancy Support
Power supplies that support cold redundancy can be enabled to go into a low-power state (that
is, cold redundant state) in order to provide increased power usage efficiency when system
loads are such that both power supplies are not needed. When the power subsystem is in Cold
Redundant mode, only the needed power supply to support the best power delivery efficiency is
ON. Any additional power supplies, including the redundant power supply, is in Cold
Standby state.
Each power supply has an additional signal that is dedicated to supporting Cold Redundancy;
CR_BUS. This signal is a common bus between all power supplies in the system. CR_BUS is
asserted when there is a fault in any power supply OR the power supplies output voltage falls
below the Vfault threshold. Asserting the CR_BUS signal causes all power supplies in Cold
Standby state to power ON.
Enabling power supplies to maintain best efficiency is achieved by looking at the Load Share
bus voltage and comparing it to a programmed voltage level through a PMBus* command.
Whenever there is no active power supply on the Cold Redundancy bus driving a HIGH level on
the bus all power supplies are ON no matter their defined Cold Redundant roll (active or Cold
Standby). This guarantees that incorrect programming of the Cold Redundancy states of the
power supply will never cause the power subsystem to shut down or become over loaded. The
default state of the power subsystem is all power supplies ON. There needs to be at least one
power supply in Cold Redundant Active state or Standard Redundant state to allow the Cold
Standby state power supplies to go into Cold Standby state.
Intel order number: G52418-006 Revision 1.6
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