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BLUESTREAK SERIES
INSTALLATION & OPERATING MANUAL
P O W E R I N G T E C H N O L O G Y
Document Number: BLUESTREAK-MAN Rev. 6
bluestreak-man-rev6-0719.indd
9.2.10
#FANOK
This signal provides an open drain output that indicates that the fans speeds are more than
80% of the required speed. The signal is normally low for the OK state but is programmable
to be normally high using the PMBus. The output is capable of supporting voltages of up
to 30V and will sink current up to 30mA. The return path for this signal is standby return.
The #FANOK signal is also available within the status bytes of the PMBus.
9.2.11
#Module Present
This signal can be used to detect if a module is present. It is connected to standby return
when the module is present. This signal can sink up to 30mA.
9.2.12
#Enable
This signal is used to enable the power supply. This pin engages after the power terminals
when plugging in the module and disengages before the power terminals when unplugging
the module. It is intended to control hot-plugging to avoid burning connector pins caused
by arcing of high currents. The return path for this signal is Sense –Ve. The #Enable pin
should be connected to Sense -Ve on the backplane for correct operation.
9.2.13
Control
This signal can be used to control the main output of the power supply in order to turn it
on and off. The default is that a low signal on this pin will turn the main output off. This
function can be changed using PMBus so that either a high signal will turn the main output
off or the pin is ignored altogether. This behaviour can allow a system to be setup so that
the main output will not come on until commanded by a supervisory circuit. The control pin
is returned to standby return. The driving circuit should be capable of sinking and sourcing
at least 0.5mA.
9.2.14
SCL, SDA
These are the serial data bus (PMBus) signals used for digital communication. This
communication bus is similar to the standard I²C bus but does vary in some ways. The
voltage levels and timing behaviour are consistent with the SMBus standard revision 1.0.
Please refer to this standard for details. For details of the PMBus protocol and commands
implemented, please refer to the PMBus standard revision 1.1 and the BLUEstreak software
manual respectively. The PMBus signals are returned to standby return. They require pull-
up resistors or active pull-up circuits to 3.3V or 5V.
9.2.15
#SMBAlert
This signal can be used in conjunction with the SCL and SDA serial bus signals to determine
when a fault or warning condition exists. The signal is latching so that if a warning or fault
condition disappears the signal will not be cleared. To clear the signal the PMBus master
must respond to the alert as detailed in the PMBus specification. Using this method provides
for a more efficient way of detecting faults than polling but polling the PMBus registers
can still be done. The #SMBAlert signal is returned to standby return. It requires pull-up
resistors or active pull-up circuits to 3.3V or 5V.
