ir3725 International Rectifier Corp., ir3725 Datasheet
ir3725
Related parts for ir3725
ir3725 Summary of contents
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... 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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... TEST CONDITION R = 25.5 kΩ T Config Reg enable bit d4 25.5 kΩ 25.5 kΩ T Driven from internal clock Driven from external clock Config Reg [d3..d0] = b‘0000 Config Reg [d3..d0] = b‘1000 www.irf.com IR3725 Data Sheet 150 )..........................1.6 °C/W JC )...........................30 °C/W JA NOTE MIN TYP MAX 3.1 2.4 75 700 1000 ...
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... VO=12V, DCR voltage = 75 mV, R =25.5kΩ, RCS1=RCS2=1.5kΩ °C j VO=12 V, DCR voltage = 75mV, RT=25.5kΩ, RCS1=RCS2=1.5kΩ – 85 °C VO=12V, DCR voltage = 75 mV, R =25.5kΩ, RCS1=RCS2=1.5kΩ – 85 °C www.irf.com IR3725 Data Sheet NOTE MIN TYP MAX 1.5 1 1.3 1 1.0 2008_12_09 ...
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... IC PIN FUNCTIONS VDD PIN This pin provides operational bias current to circuits internal to the IR3725. Bypass it with a high quality ceramic capacitor to the GND pin. GND PIN This pin returns operational bias current to its source also the reference to which the voltage VO is ...
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... This device is considered a slave, and therefore uses the SCL as an input only. SDA SDA is monitored as data input during master to slave transactions, and is driven as data output during slave to master transactions as indicated in the Packet Protocol section to follow. www.irf.com IR3725 Data Sheet 2008_12_09 ...
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... CS1 CS2 full scale) IR3725 PowerMode - Error [%] ( DCR 20% 18% 16% 14% 12% 10 0.00 0.06 0.08 IR3725 PowerMode - Error [%] ( full scale) DCR 20% 18% 16% 14% 12% 10 0.020 0.025 0.000 0.001 0.002 0.003 0.004 0.005 0.006 0.007 0.008 www.irf.com IR3725 Data Sheet = 25.5 k Ω ...
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... IR3725 CurrentMode - Error [%] ( 20% 18 12% 10 0.00 0.02 0.04 V [V] DCR IR3725 CurrentMode - Error [% ] ( 20% 18% 16% 14% 12% 10 0.000 0.002 0.004 V [V] DCR Page IR3725 CurrentMode - Error [%] ( full scale) DCR 20% ...
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... I L 12V in L DCR R CS1A C R CS1 CS2A C CS2 VCS1 VDD IR3725 VT GND R th Figure 1 Functional Description Diagram www.irf.com IR3725 Data Sheet . V is defined where I equals V *(Rcs1 *DCR). The full scale power P is the CS1B R CS2B VCS2 ...
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... CS2 ceramic dielectric with a value between 0.1 μF and 10 μF. SHUNT R CS1 C CS2 VDD VCS1 IR3725 VT GND Figure 2 Resistor Sensing Circuit www.irf.com IR3725 Data Sheet and R such that this current through CS2 R CS2 VCS2 VO SDA SCL ALERT# ADDR 2008_12_09 ...
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... CS1 order to minimize ripple current in C CS1 1 = ⋅ CS1 SUM = ⋅ CS2 SUM www.irf.com IR3725 Data Sheet ) + R CS2 . Let and solve for Rsum. sum that is larger than CS1 . The next CS1 CS2 into the R equation the following ...
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... Equation 4 may be written as a function of temperature using equations 1 and 3 as follows: I With Rs and Rp as additional free variables, use a spreadsheet to solve equation 4 for the desired full scale current while minimizing the I over temperature. www.irf.com IR3725 Data Sheet ⎛ ⎞ ⎛ ⎞ ⎜ ...
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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 DCR ( CS1 CS2 well as parameters internal to the IR3725. The tolerance of these components increases the total power or current error ...
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... Averaging interval (MSB) d4 Shutdown d5 External clock d6 OUTPUT config (LSB) d7 OUTPUT config (MSB) d8 ALERT# configuration d9 ALERT# threshold (LSB + 2) d10 ALERT# threshold d11 ALERT# threshold d12 ALERT# threshold d13 ALERT# threshold d14 ALERT# threshold d15 ALERT# threshold (MSB) www.irf.com IR3725 Data Sheet 2008_12_09 ...
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... RESERVED COMMAND (decimal) CODES 256 0 Command codes D2h through D5h, D7h, and D8h 256 are reserved for manufacturing use only and could -256 lead to undesirable device behavior. 256 -256 yields the www.irf.com IR3725 Data Sheet OUTPUT REGISTER Output variable LSB 2008_12_09 ...
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... Table 1 Slave R A Data Byte Low Address See Table 1 www.irf.com IR3725 Data Sheet Data Byte High d14 d13 d12 d11 d10 Data Byte High d15 d14 d13 d12 d11 d10 ...
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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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... Data and specifications subject to change without notice. This product has been designed and qualified for the Consumer market. Qualification Standards can be found on IR’s Web site. Visit us at www.irf.com for sales contact information . www.irf.com IR3725 Data Sheet TAC Fax: (310) 252-7903 2008_12_09 ...