Features and Benefits
- Indicates Accumulated Battery Charge and Discharge
- High Accuracy Analog Integration
- ADC Measures Battery Voltage and Temperature
- Integrated Temperature Sensor
- High Side Sense
- 1% Voltage and Charge Accuracy
- ±50mV Sense Voltage Range
- SMBus/I2C Interface
- Configurable Alert Output/Charge Complete Input
- 2.7V to 5.5V Operating Range
- Quiescent Current Less than 100μA
- Small 6-Pin 2mm × 3mm DFN package
The LTC2942 measures battery charge state, battery voltage and chip temperature in handheld PC and portable product applications. Its operating range is perfectly suited for single-cell Li-Ion batteries. A precision coulomb counter integrates current through a sense resistor between the battery’s positive terminal and the load or charger. Battery voltage and on-chip temperature are measured with an internal 14-bit No Latency ΔΣ™ ADC. The three measured quantities (charge, voltage and temperature) are stored in internal registers accessible via the on-board SMBus/I2C interface.
The LTC2942 features programmable high and low thresholds for all three measured quantities. If a programmed threshold is exceeded, the device communicates an alert using either the SMBus alert protocol or by setting a flag in the internal status register.
The LTC2942 requires only a single low value sense resistor to set the measured current range.
|Integrated Sense Resistor|
- Low Power Handheld Products
- Cellular Phones
- MP3 Players
Product Lifecycle Production
At least one model within this product family is in production and available for purchase. The product is appropriate for new designs but newer alternatives may exist.
Evaluation Kits (1)
Demonstration circuit 1496C-B features the LTC2942, a battery gas gauge that measures battery charge and discharge, battery voltage and chip temperature. The demo board includes an external 100mΩ (default) sense resistor for a maximum current measurement of 500mA (±50mV current sense voltage range). The sense resistor can be changed; however the software only accepts sense resistors between 0.1mΩ to 5Ω. The 2.7V to 5.5V operating range is perfectly suited for single cell Li-Ion batteries.
A precision analog coulomb counter integrates current through the sense resistor between the battery’s positive terminal and the load or charger. The LTC2942 adds battery voltage and on-chip temperature measurement with an internal 14-bit No Latency ΔΣ™ ADC. The three measured quantities (charge, voltage and temperature) are stored in internal registers accessible via the on-board SMBus/I2C interface.
Tools & Simulations
LTspice® is a powerful, fast and free simulation software, schematic capture and waveform viewer with enhancements and models for improving the simulation of analog circuits.
Models for the following parts are available in LTspice:
Linduino is Analog Devices’ Arduino compatible system for developing and distributing firmware libraries and example code for our integrated circuits. Each Linduino-supported product includes an example main program, defined in the LTSketchbook/Part Number folder and driver code, defined in the LTSketchbook/libraries folder.
Technical Articles (2)
ADI has always placed the highest emphasis on delivering products that meet the maximum levels of quality and reliability. We achieve this by incorporating quality and reliability checks in every scope of product and process design, and in the manufacturing process as well. "Zero defects" for shipped products is always our goal.
Sample & Buy
The USA list pricing shown is for BUDGETARY USE ONLY, shown in United States dollars (FOB USA per unit for the stated volume), and is subject to change. International prices may differ due to local duties, taxes, fees and exchange rates. For volume-specific price or delivery quotes, please contact your local Analog Devices, Inc. sales office or authorized distributor. Pricing displayed for Evaluation Boards and Kits is based on 1-piece pricing.