Precision Voltage Meter

About this project

VoltEdge interfaces the ADS1115 16-bit ADC to an ESP32 using raw I2C register programming — no library. The ADS1115 offers 65536 discrete voltage steps where Arduino's built-in ADC offers only 1024, making it 64× more precise. The project configures the chip's 16-bit config register to scan all four AIN channels in sequence using single-shot conversion mode, automatically selects the most precise Programmable Gain Amplifier (PGA) range for each reading (auto-ranging from ±6.144V down to ±0.256V), and measures the differential voltage between AIN0 and AIN1 — demonstrating bridge-sensor technique. The onboard comparator is configured with a programmable threshold on AIN0: exceeding it asserts the ALERT pin and triggers an LED alarm. All four channel voltages, the differential reading, and gain levels stream to an SSD1306 OLED and a live ESP32 Wi-Fi AP web dashboard at 192.168.4.1.

What you get

• Complete, commented source code
• Full components list with quantities
• Pin-by-pin wiring guide and connection table
• Step-by-step upload and testing guide
• Project report (.docx, IEEE style)
• Presentation slides (.pptx)