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LTC2945: Wide Range I2C Power Monitor Data Sheet (Rev. C)9/17/2015PDF2 M
Overview
Features and Benefits
- Rail-to-Rail Input Range: 0V to 80V
- Wide Input Supply Range: 2.7V to 80V
- Shunt Regulator for Supplies >80V
- ΔΣ ADC with less than ±0.75% Total Unadjusted Error
- 12-Bit Resolution for Current and Voltages
- Internal Multiplier Calculates 24-Bit Power Value
- Stores Minimum and Maximum Values
- Alerts When Limits Exceeded
- Additional ADC Input Monitors an External Voltage
- Continuous Scan and Snapshot Modes
- Shutdown Mode with IQ < 80μA
- Split SDA for Opto-Isolation
- Available in 12-Lead 3mm × 3mm QFN and MSOP Packages
- AEC-Q100 Qualified for Automotive Applications
Product Details
The LTC2945 is a rail-to-rail system monitor that measures current, voltage, and power. It features an operating range of 2.7V to 80V and includes a shunt regulator for supplies above 80V to allow flexibility in the selection of input supply. The current measurement range of 0V to 80V is independent of the input supply. An onboard 0.75% accurate 12-bit ADC measures load current, input voltage and an auxiliary external voltage. A 24-bit power value is generated by digitally multiplying the measured 12-bit load current and input voltage data. Minimum and maximum values are stored and an overrange alert with programmable thresholds minimizes the need for software polling. Data is reported via a standard I2C interface. Shutdown mode reduces power consumption to 20μA.
The LTC2945 I2C interface includes separate data input and output pins for use with standard or opto-isolated I2C connections. The LTC2945-1 has an inverted data output for use with inverting opto-isolator configurations.
APPLICATIONS
- Telecom Infrastructure
- Industrial
- Automotive
- Consumer
Product Categories
Product Lifecycle
Recommended for New Designs
This product has been released to the market. The data sheet contains all final specifications and operating conditions. For new designs, ADI recommends utilization of these products.
Evaluation Kits (1)
Documentation & Resources
-
R567 Reliability Data3/23/2018PDF122K
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DC1697A - Demo Manual6/13/2016PDF470K
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Power System Manager and Super Sequencer Selection Guide2/23/2018PDF4M
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Power and Thermal Monitoring1/9/2017PDF1M
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Wide Range I2C Power Monitor10/22/2012PDF941K
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Reference Designs (1)
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PCN-PDN Information
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Pricing displayed is based on 1-piece. The USA list pricing shown is for budgetary use only, shown in United States dollars (FOB USA per unit), and is subject to change. International prices may vary due to local duties, taxes, fees and exchange rates.