1 Features

• Input Voltage Range: 2.9 V to 17 V
• I²C/SMBus Interface and PMBus Compliant Command Structure
• Programmable 25-mV or 46-mV Current Limit Threshold
• Configurable Circuit Breaker Protection for Hard Shorts
• Configurable Undervoltage and Overvoltage Lockouts With Hysteresis
• Remote Temperature Sensing With Programmable Warning and Shutdown Thresholds
• Detection and Notification of Damaged MOSFET Condition
• Real Time Monitoring of V_IN, V_OUT, I_IN, P_IN, V_AUX With 12-Bit Resolution and 1-kHz Sampling Rate
• Current Measurement Accuracy: ±1% Over Temperature
• Power Measurement Accuracy: ±2% Over Temperature
• True Input Power Measurement Using Simultaneous Sampling of V_IN and I_IN Accurately Averages Dynamic Power Readings
• Averaging of V_IN, I_IN, P_IN, and V_OUT Over Programmable Interval Ranging from 0.001 to 4 Seconds
• Programmable WARN and FAULT Thresholds with SMBA Notification
• Black Box Capture of Telemetry Measurements and Device Status Triggered by WARN or FAULT Condition
• 24-Lead WQFN Package

2 Applications

• Server Backplane Systems
• Basestation Power Distribution Systems
• Solid State Circuit Breakers

3 Description

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 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 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.

1. For all available packages, see the orderable addendum at the end of the data sheet.

Typical Application Schematic