Intel SC5299WS User Manual

2.4.4.2 

Over-voltage Protection (OVP) 

Each DC/DC converter output on the cage has individual OVP circuits built in and is locally 
sensed. The PS+cage combo will shut down and latch off after an over-voltage condition 
occurs. This latch can be cleared by toggling the PSON

#

 signal or by an AC power interruption.  

The following table defines the over-voltage limits. The values are measured at the cage 
harness connectors. The voltage does not exceed the maximum levels when measured at the 
power pins of the output harness connector during any single point of fail. The voltage does not 
trip any lower than the minimum levels when measured at the power pins of the cage connector. 

Output Voltage 

OVP MIN (V) 

OVP MAX (V) 

+3.3V 3.9 

4.5 

+5V 5.7 

6.5 

-12V -13.3 

-14.5 

+12V1/2/3/4/5 See 

Power Supply specification 

+5vsb 

See Power Supply specification 

 

2.4.5 

Control and Indicator Functions (Hard-wired) 

The following sections define the input and output signals from the power distribution board. 

Signals that can be defined as low true use the following convention:   

#

 = low true 

 

2.4.5.1 

PSON

# 

Input and Output Signals 

The PSON

#

 signal is required to remotely turn on/off the power supply. PSON

#

 is an active low 

signal that turns on the +3.3V, +5V, +12V, and -12V power rails. When this signal is not pulled 
low by the system, or left open, the outputs (except for the +5VSB) turn off. This signal is pulled 
to a standby voltage by a pull-up resistor internal to the power supply.