The UCC39002 device is an advanced, high-performance, and low-cost load share controller
that provides all necessary functions to parallel multiple independent power supplies or DC-to-DC
modules. Targeted for high-reliability applications in server, workstation, telecom, and other
distributed power systems, the controller is suitable for N+1 redundant systems or high current
applications where off-the-shelf power supplies must be paralleled.
The BiCMOS UCC39002 is based on the automatic master or slave architecture of the UC3902
and UC3907 load share controllers. The device provides better than 1% current share error between
modules at full load by using a very low offset post-package-trimmed current sense amplifier and a
high-gain negative feedback loop. And with the amplifier’s common-mode range of 0 V to the supply
rail, the current sense resistor, RSHUNT, can be placed in either the GND
return path or in the positive output rail of the power supply.