Fingerprint Sensor AS608 - A Beginner's Guide
One touch can replace keys. This project uses an optical fingerprint sensor to enroll users and then grant access with a quick scan.
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Coulomb Counter Breakout — LTC4150 Battery Charge Tracker
The LTC4150 Coulomb Counter Breakout precisely tracks how much charge (in coulombs) flows into and out of a battery, giving you an accurate picture of remaining battery capacity. Unlike simple voltage-based fuel gauges, coulomb counting works reliably under varying load conditions — making it the gold standard for battery state-of-charge estimation in portable projects.
Technical specifications
| Chip | LTC4150 (Analog Devices / Linear Tech) |
|---|---|
| Measurement | Charge flow (coulombs) |
| Output | Digital pulse (interrupt) per 0.1707 mAh |
| Polarity pin | Indicates charge vs discharge direction |
| Supply | 2.7–8.5V |
Frequently Asked Questions
How is this different from a voltage-based fuel gauge? Voltage readings fluctuate with load. Coulomb counting measures actual charge flow, so it's accurate regardless of current draw. For an I2C fuel gauge, see the DFRobot Fuel Gauge.
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Returns: 7-day inspection window for DOA units. Email proof of issue and we ship a replacement.
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