LM25056_16 Datasheet, PDF (1/39 Pages) Texas Instruments – System Power Measurement IC

LM25056
www.ti.com
SNVS784A – JANUARY 2012 – REVISED APRIL 2013
LM25056 System Power Measurement IC with PMBus
Check for Samples: LM25056
FEATURES
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•234 Input Voltage Range: 3V to 17V
• I²C/SMBus Interface with PMBus Compliant
Command Structure
• Remote Temperature Sensing with
Programmable Warning and Shutdown
Thresholds
• Real Time Monitoring of V_IN, I_IN, P_IN, V_AUX with
12-bit Resolution and 1 kHz Sampling Rate
• 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_AUX Over
Programmable Interval Ranging from 0.001 to
4 Seconds
• User Programmable WARN and FAULT
Thresholds with SMBA Notification
• Black Box Capture of Telemetry
Measurements and Device Status Triggered by
WARN and FAULT Conditions
• Full Featured Application Development
Software
• WQFN-24 Package
APPLICATIONS
• Server Backplane Systems
• Base Station Power Distribution Systems
• Subsystem Power Measurement
DESCRIPTION
The LM25056 combines high performance analog
and digital technology with a PMBus™ compliant
SMBus™/I²C interface to accurately measure the
operating conditions of electrical systems including
computing and storage blades connected to a
backplane power bus. The LM25056 continuously
supplies real-time power, voltage, current, and
temperature data to the system management host via
the SMBus interface.
The LM25056 monitoring block captures both real-
time and average values of subsystem operating
parameters (V_IN, I_IN, P_IN, V_AUX) as well as peak
power. Accurate power measurement is
accomplished by measuring the product of the input
voltage and current through a shunt resistor.
LM25056 current measurement has a ±1.5%
accuracy over the temperature range of -40°C to
+85°C with operation from -40°C to +125°C. A black
box (Telemetry/Fault Snapshot) function captures and
stores telemetry data and device status in the event
of a warning or a fault.
Typical Application Schematic
+12V
RS
MMBT3904
VDD
NC
NC
SMBus
Interface
CIN
VIN
ADR2
ADR1
ADR0
ENABLE
VS+
VS- DIODE
VAUX
LM25056
VREF
SMBA
SDA
SCL
DGND AGND
VDD
VIN
VOUT
POL
REGULATOR
CVREF
CVDD
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Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
SMBus is a trademark of Intel Corporation.
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PMBus is a trademark of SMIF, Incorporated.
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All other trademarks are the property of their respective owners.
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PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
Copyright © 2012–2013, Texas Instruments Incorporated