UC3902D

The UC3902D from Texas Instruments is a specialized integrated circuit designed to balance current draw from independent, paralleled power supplies. This 8-pin device facilitates load sharing by adjusting each supply's output current proportionally to a shared voltage bus.

Key electrical specifications include an operating voltage range of 2.7V to 20V and a typical current consumption of 4mA. The device supports features such as load sharing, programmable loop compensation, remote sense, and undervoltage lockout (UVLO) protection. It is compatible with both Buck and Flyback topologies.

Packaged in an 8-SOIC surface mount configuration, the UC3902D is suitable for applications requiring reliable current distribution across multiple power sources. Its design minimizes the need for external components, simplifying integration into existing power supply designs. The controller automatically designates the master supply based on the highest regulated voltage, driving the share bus and trimming other supplies accordingly.

This IC is particularly useful in systems where multiple power supplies are paralleled to increase current capability or provide redundancy. The UC3902D ensures that each supply contributes proportionally to the total load, enhancing system stability and efficiency.