PI2123 Datasheet, PDF (13/20 Pages) Vicor Corporation – 15 Volt, 15 Amp Full-Function Active ORing Solution

Figure 18: Plot of PI2123 response time to reverse current detection
Application Information
The PI2123 is designed to replace ORing diodes in
high current, low voltage redundant power
architectures. Replacing a traditional diode with a
PI2123 will result in significant power dissipation
reduction as well as board space reduction,
efficiency improvement and additional protection
features. This section describes in detail the
procedure to follow when designing with the PI2123
Active ORing solution.
Fault Indication:
The FT output pin is an open collector and should
be pulled up to the logic voltage or to the controller
VC via a resistor (10KΩ)
Blanking Timer:
Connect the blanking timer pin (BK) to GND to
program the device for the fastest reverse
comparator response time of 160ns typical. To
increase the blanking time, connect the BK pin to
GND via a resistor to avoid the fault response to
short reverse current pulses. Refer to the plot in the
reverse comparator functional description for
resistor values versus the reverse blanking time.
Auxiliary Power Supply (Vaux):
Vaux is an independent power source required to
supply power to the VC input. The Vaux voltage
should be 6V higher than Vin (redundant power
source output voltage) to fully enhance the internal
MOSFET.
A bias resistor (Rbias) is required if Vaux is higher
than 15V. Rbias should be connected between the
VC pin and Vaux.
Minimize the resistor value for low Vaux voltage
levels to avoid a voltage drop that may reduce the
Picor Corporation • picorpower.com
PI2123
Rev 1.0 Page 13 of 20