With its advanced features, it provides reliable solutions for utility operators, extending the lifespan of smart meters, optimizing operational efficiency, and minimizing maintenance costs.
Smart water, gas, and heat meters are evolving rapidly, adding new features and capabilities while still needing to operate for at least 10 years. This long operational life increases the demand on battery performance. System malfunctions, whether caused by hardware or software issues, can negatively affect battery life, reducing the overall lifespan of the meter. To address these challenges, this reference design integrates advanced battery and system monitoring solutions, providing service operators with critical insights into product life expectancy. These insights enable operators to optimize meter replacement schedules, reduce downtime, and minimize service costs.
The design TIDA-01546 by Texas Instruments (TI) focuses on innovative monitoring systems for battery-powered smart flow meters, ensuring both battery and system health throughout the meter’s lifespan. The battery monitoring subsystem delivers precise energy measurements and accurate projections of the battery’s State of Health (SOH), allowing operators to predict when a battery will need replacement. In addition, the system monitoring subsystem protects against overcurrent conditions, which can significantly reduce battery life. These techniques help extend the effective life of smart meters and improve the total cost of ownership for utility operators.
This design includes several key features to optimize performance. It provides real-time SOH monitoring for non-rechargeable lithium batteries, along with accurate end-of-service predictions to prevent unexpected failures. Low-power system monitoring is achieved using the ADS7142 SAR ADC and the LPV521 op-amp, ensuring minimal power consumption. The design also incorporates a single-channel load switch to manage system load efficiently, reducing unnecessary power drain. It supports multiple battery chemistries, including Lithium Thionyl Chloride (LiSOCl₂) and Lithium Manganese Dioxide (LiMnO₂), ensuring flexibility in different applications. The system’s ultra-low standby power consumption, as low as 1 µA for both battery and system health monitoring, further enhances energy efficiency.
The solution leverages several advanced components to ensure optimal functionality. The bq35100 battery fuel gauge and EOS monitor provide configurable fuel gauging for non-rechargeable lithium batteries without requiring forced discharge. The ADS7142 is a dual-channel, nanopower sensor monitor that consumes only 900 nW and includes programmable high/low thresholds for generating alerts. The LPV521 nanopower amplifier, consuming just 351 nA, is ideal for ultra-long battery life applications with an operating range between 1.6 V and 5.5 V. The TPS22860 load switch offers ultra-low leakage and supports continuous currents up to 200 mA, providing flexible load management across a wide voltage range. This enhanced reference design ensures adaptability for various applications, making it suitable for smart gas, water, and heat meters.
TI has tested this reference design. It comes with a bill of materials (BOM), schematics, assembly drawing, printed circuit board (PCB) layout, and more. The company’s website has additional data about the reference design. To read more about this reference design, click here.
