Quantity   Component name
1 × ESP32-S3 The ESP32 line was chosen for it's compatibility with open source software, WiFi capability and low cost. Using WiFi as the wireless protocol removes the need for a hub, which adds cost and complexity. However, this makes meeting battery life and range requirements more difficult vs a standard like LoRa.
1 × SLG47004V A low cost programmable mixed signal logic chip used for deep sleep logic like rotation counting, interrupt generation and sensor duty cycling to reduce power. Most of the logic will be designed using digital logic because it is significantly lower power than a CPU. For example, the ESP32-S3 ultra low processor consumers 300uA. Digital logic can do much better.
1 × ALT021-10E An ultra sensitive tunneling magnetoresistance (TMR) sensor. This is the only sensor I've found that is sensitive enough to measure the rotation of the water meter magnet without amplification. While this works in V2, the next design will include a small amplification stage to add room for margin.
1 × PCF8563 Clock and Timer ICs / A basic real-time clock for clock generation for the SLG47004V​ and time keeping. The ESP32-S3 RTC does not have an external clock output so this IC was used.Real-Time Clocks
1 × IN-PI22TAT5R5G5B An RGB LED for user feedback. Primarily chosen for it's low height to fit under the the LED lens.
1 × MB85RC64TA An FRAM memory chip for water usage storage. FRAM offers faster read and write speeds, higher endurance, lower power consumption, instantaneous writes, and bit-level addressability compared to EEPROM, making it well-suited for applications that require frequent data updates and low power consumption.
1 × Miscellaneous Accessories See the github for a complete BOM with things like resistors, antennas, PCB and more