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Basic Explanation of my System: The proposed design is a battery-powered wearable device that integrates advanced sensing and power management features. The system operates primarily from a single...
#1: Initial revision
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newbie
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2025-12-16T16:10:59Z (9 months ago)
Wearable device Battery life calculation
Basic Explanation of my System: The proposed design is a battery-powered wearable device that integrates advanced sensing and power management features. The system operates primarily from a single-cell Li-ion battery (3.7 V nominal) and includes a USB Type-C interface for charging and external power supply. The device uses a battery charger with power-path management ( [BQ24075](https://www.ti.com/lit/ds/symlink/bq24075.pdf)) to ensure seamless operation: When USB power is connected, the system is powered directly from the USB input while simultaneously charging the battery. When USB is disconnected, the system automatically switches to battery power without interruption. A [fuel gauge IC](https://www.analog.com/media/en/technical-documentation/data-sheets/max17048-max17049.pdf) monitors battery health parameters such as voltage, state of charge (SOC), and remaining capacity, reporting these to the microcontroller via I²C. The system includes an electrochemical front end ([AD5941](https://www.analog.com/media/en/technical-documentation/data-sheets/ad5940-5941.pdf)) with a 16-bit ADC for high-precision sensor measurements. Sensor signals are routed through a multiplexer ([MUX](https://www.ti.com/lit/ds/symlink/tmux1108.pdf)) to the AD5941, which interfaces with an STM32 microcontroller development board for data acquisition and processing. The power delivery circuit consists of a [buck boost converter](https://www.analog.com/media/en/technical-documentation/data-sheets/3531fb.pdf) which will convert the battery voltage (3V to 3.7V) to 4V. The output of this buck-boost is connected to an [LDO](https://www.analog.com/media/en/technical-documentation/data-sheets/adp7118.pdf) which will generate the 3.3V required for the board. Below is my power tree and battery capacity calculation.May I know it is fine or not.  My power Delivery schematic is also given below. May I know your thoughts about this.Can I go ahead with this design. Mine is a 16bit ADC that is why I am going with this configuration.  