LTC2945 - Wide Range I2C Power Monitor
Features
- Rail-to-Rail Input Range: 0V to 80V
- Wide Input Supply Range: 2.7V to 80V
- Shunt Regulator for Supplies >80V
- Δ∑ 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
- Additional ADC Input Monitors an External Voltage
- Internal Digital Multiplier Calculates Power
- 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
Typical Application
Description
The LTC2945 is a rail-to-rail system monitor that mea- sures 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 program- mable 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.
Packaging
For complete and up to date package information and drawings, please refer to our packaging page
QFN-12, MS-12
Order Info
- Part numbers ending in PBF are lead free. Please contact LTC marketing for information on lead based finish parts.
- Part numbers containing TR or TRM are shipped in tape and reel or 500 unit mini tape and reel, respectively
- Please refer to our general ordering information or the product datasheet for more details
Package Variations and Pricing
| Part Number | Package | Pins | Temp | Price (1-99) | Price (1k)* | RoHS Data |
|---|---|---|---|---|---|---|
| LTC2945CMS#PBF | MSOP | 12 | C | $5.10 | $3.57 | View |
| LTC2945CMS#TRPBF | MSOP | 12 | C | $3.63 | View | |
| LTC2945CMS-1#PBF | MSOP | 12 | C | $5.10 | $3.57 | View |
| LTC2945CMS-1#TRPBF | MSOP | 12 | C | $3.63 | View | |
| LTC2945CUD#PBF | QFN | 12 | C | $5.10 | $3.57 | View |
| LTC2945CUD#TRPBF | QFN | 12 | C | $3.63 | View | |
| LTC2945CUD-1#PBF | QFN | 12 | C | $5.10 | $3.57 | View |
| LTC2945CUD-1#TRPBF | QFN | 12 | C | $3.63 | View | |
| LTC2945IMS#PBF | MSOP | 12 | I | $5.87 | $4.11 | View |
| LTC2945IMS#TRPBF | MSOP | 12 | I | $4.17 | View | |
| LTC2945IMS-1#PBF | MSOP | 12 | I | $5.87 | $4.11 | View |
| LTC2945IMS-1#TRPBF | MSOP | 12 | I | $4.17 | View | |
| LTC2945IUD#PBF | QFN | 12 | I | $5.87 | $4.11 | View |
| LTC2945IUD#TRPBF | QFN | 12 | I | $4.17 | View | |
| LTC2945IUD-1#PBF | QFN | 12 | I | $5.87 | $4.11 | View |
| LTC2945IUD-1#TRPBF | QFN | 12 | I | $4.17 | View | |
| Buy Now • Request Samples | ||||||
Demo Boards
Linear Technology offers many demo boards free of charge to qualified customers. Contact your local sales office or distributor to inquire about a demo board. Certain demo boards are also available for sale via credit card on this website. Demo boards are for evaluation purposes only. It remains the customer’s responsibility to verify proper and reliable operation in the actual end application.| Part Number | Description | Price | Documentation |
|---|---|---|---|
| DC1697A | LTC2945: Wide Range I2C Power Monitor (requires DC590) | $75.00 | |
| Buy Now | |||
Companion Boards
| Part Number | Description | Price | Documentation |
|---|---|---|---|
| DC590B | USB Serial Controller for Linear Technology QuikEval Demo Boards | $50.00 | |
| Buy Now | |||
Applications
- Telecom Infrastructure
- Industrial
- Automotive
- Consumer
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Technical Support
- For immediate technical assistance, contact your local sales office or distributor or call 1-800-4-LINEAR (US customers only) or 408-432-1900.
- For less urgent requests, please complete our Technical Support Request Form. Please allow 2-3 business days for reply.