IR3725MTRPBF International Rectifier, IR3725MTRPBF Datasheet
IR3725MTRPBF
Specifications of IR3725MTRPBF
Related parts for IR3725MTRPBF
IR3725MTRPBF Summary of contents
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... L DCR C CS1 C CS2 +12V Return ORDERING INFORMATION Device IR3725MTRPBF IR3725MPBF Page INPUT POWER MONITOR WITH DIGITAL INTERFACE DESCRIPTION The IR3725 is a highly configurable power monitor IC that uses proprietary digital technology to measure a 12V rail current, its voltage, or its average power over a user specified time interval. Configuration and result reporting are managed through a serial digital interface ...
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ABSOLUTE MAXIMUM RATINGS All voltages referenced to GND VDD: ................................................................3.9V ALERT#:...........................................................3.9V ALERT#............................................. < VDD + 0.3V VCS1, VCS2, VO ...........................................25.0V All other Analog and Digital pins ......................3.9V Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to ...
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PARAMETER ACCURACY Power measurement error Voltage measurement error Current measurement error NOTES: 1. Guaranteed by design, not tested in production 2. Assumes no error contributed by external components BLOCK DIAGRAM Page TEST CONDITION VO=12V, DCR voltage = ...
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PIN DESCRIPTION NAME NUMBER I/O LEVEL VCS1 1 Analog 12V VCS2 2 Analog 12V VO 3 Analog 12V VT 4 Analog GND 5 0V VDD 6 3.3V EXTCLK 7 3.3V Digital ADDR 8 3.3V Digital SCL 9 3.3V Digital SDA ...
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ADDR PIN The ADDR pin is an input that establishes the serial bus address. Valid addresses are selected by grounding, floating, or wiring to VDD the ADDR pin. Table 1, “User Selectable Addresses”, provides a mapping of possible selections. Bypass ...
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TYPICAL PERFORMANCE CHARACTERISTICS (One device tested using “Resistor Sensing Circuit”, VDD = 3 uses 1.5 k Ω full scale uses R CS1 CS2 Each data point is average of eight samples.) IR3725 ...
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IR3725 CurrentMode - Error [%] ( 20% 18 12% 10 0.00 0.02 0.04 V [V] DCR IR3725 CurrentMode - ...
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FUNCTIONAL DESCRIPTION Please refer to the Functional Description Diagram below. Power flow through the inductor is the product of output voltage VO times the inductor current I average voltage V will be developed across the DCR inductor as a result ...
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RESISTOR CURRENT SENSING APPLICATION The voltage on the shunt resistor of the circuit below is directly proportional to the current from the source. Shunts developing used. Accuracy is enhanced at the higher voltage. ...
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INDUCTOR DCR CURRENT SENSING APPLICATION Referring to the Functional Description Diagram, it can be seen that the shunt function can be accomplished by the DC resistance of the inductor that is already present. Omitting the resistive shunt reduces BOM cost ...
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THERMAL COMPENSATION FOR INDUCTOR DCR CURRENT SENSING The positive temperature coefficient of the inductor DCR can be compensated if R varies inversely T proportional to the DCR. DCR of a copper coil function of temperature, is approximated by ...
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ERROR MANAGEMENT Component value errors external to the IR3725 contribute to power and current measurement error. The power reported by the IR3725 is a function not only of actual power or current, but also of products and quotients of R ...
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CONFIGURATION REGISTER A configuration register is maintained via the serial bus MFR_SPECIFIC_00 command, code # D0h. The low order nibble (d3, d2, d1, d0) contains a binary number N from zero to eight. The averaging interval milliseconds. ...
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OUTPUT REGISTER The output register is loaded with a two’s compliment factor of voltage, current, or power, depending on the last request loaded into the configuration register. Serial bus “Direct Data Format” is used. The value of the output register ...
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PACKET PROTOCOL S = Start Condition W = Bus write ( Bus read ( Acknowledge for ACK, =1 for NACK P = Stop Condition = master to slave = slave to master Bus Write ...
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PCB PAD AND COMPONENT PLACEMENT The figure below shows a suggested pad and component placement. Page www.irf.com IR3725 Data Sheet 2008_12_09 ...
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SOLDER RESIST The figure below shows a suggested solder resist placement. Page www.irf.com IR3725 Data Sheet 2008_12_09 ...
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STENCIL DESIGN The figure below shows a suggested solder stencil design. Page www.irf.com IR3725 Data Sheet 2008_12_09 ...
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PACKAGE INFORMATION 12L DFN LEAD FREE IR WORLD HEADQUARTERS: 233 Kansas St., El Segundo, California 90245, USA Tel: (310) 252-7105 Page Data and specifications subject to change without notice. This product has been ...