LM25066A

The LM25066A combines a high-performance hot-swap controller with a PMBus™ compliant SMBus/I²C interface to accurately measure, protect and control the electrical operating conditions of computing and storage blades connected to a backplane power bus. The LM25066A continuously supplies real-time power, voltage, current, temperature and fault data to the system management host via the SMBus interface.

The LM25066A control block includes a unique hot-swap architecture that provides current and power limiting to protect sensitive circuitry during insertion of boards into a live system backplane, or any other power source. A fast acting circuit breaker prevents damage in the event of a short circuit on the output. The input undervoltage and overvoltage levels and hysteresis are configurable, as well as the insertion delay time and fault detection time. A temperature monitoring block on the LM25066A interfaces with a low-cost external diode for monitoring the temperature of the external MOSFET or other thermally sensitive components. The POWER GOOD output provides a fast indicator when the input and/or output voltages are outside their programmed range. LM25066A current measurement accuracy is ±1% over temperature.

The LM25066A monitoring block computes both the real-time and average values of subsystem operating parameters (V_IN, I_IN, P_IN, V_OUT) as well as the peak power. Accurate power averaging is accomplished by averaging the product of the input voltage and current. A black box (Telemetry/Fault Snapshot) function captures and stores telemetry data and device status in the event of a warning or a fault.