The LM25066 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 LM25066 continuously supplies real-time power, voltage, current, temperature and fault data to
the system management host via the SMBus interface.
The LM25066 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 hot 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 LM25066 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. LM25066 current measurement accuracy is ±2.4% over temperature.
The LM25066 monitoring block computes both the real-time and average values of subsystem
operating parameters (VIN, IIN,
PIN, VOUT) 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.