Dual sensor breakout

BME280 + MPU6050 Dual Sensor Breakout Board — IoT PCB Design

A compact dual-sensor breakout board combining the BME280 environmental sensor (temperature, humidity, pressure) and MPU6050 IMU (accelerometer + gyroscope) on a single 2-layer PCB. I2C interface, 3.3V regulated, with proper decoupling and logic-level compatibility — Gerber-ready.

Overview

This project is a dual-sensor breakout board combining two of the most widely used sensors in IoT and robotics applications onto a single compact PCB. The BME280 provides environmental data — temperature, humidity, and barometric pressure — while the MPU6050 provides 6-axis inertial measurement — 3-axis accelerometer and 3-axis gyroscope.

Both sensors share the I2C bus with separate configurable addresses. The board includes onboard 3.3V regulation, I2C pull-up resistors, and full decoupling — so it connects directly to any microcontroller (Arduino, ESP32, STM32) without additional components.

This breakout demonstrates the ability to design compact sensor hardware for IoT products: proper I2C bus design, mixed-signal layout awareness, and careful decoupling on noise-sensitive sensor circuits.

Specifications

Design Highlights

Shared I2C Bus with Address Flexibility

Both sensors share the same SDA/SCL lines. Address select pads (SDO for BME280, AD0 for MPU6050) are exposed as solder jumpers, allowing the I2C address of each sensor to be configured — useful when running multiple boards on the same bus.

Onboard 3.3V Regulation

The AMS1117-3.3 LDO accepts 3.3V–5V input and regulates down to a clean 3.3V for both sensors. Input and output bulk capacitors ensure stability. Allows the board to be powered directly from a 5V Arduino without any external regulation.

Proper I2C Pull-Up Resistors

4.7kΩ pull-up resistors on SDA and SCL ensure correct I2C bus voltage levels. Values selected for reliable communication up to 400 kHz (Fast Mode) across the expected trace lengths and capacitance.

Sensor Decoupling

Each sensor has dedicated 100nF ceramic decoupling capacitors placed as close as possible to the VCC and VDDIO pins — minimising supply noise coupling into the sensitive analog and MEMS measurement circuits.

Compact Layout

Both ICs, regulation circuitry, decoupling, and pull-ups are placed within a compact footprint suitable for embedding in drone flight controllers, weather stations, wearables, and IoT sensor nodes.

Repository Structure

project4-dual-sensor-breakout/
├── schematic/
│   └── dual_sensor_breakout.kicad_sch
├── pcb/
│   └── dual_sensor_breakout.kicad_pcb
├── gerbers/
│   ├── dual_sensor_breakout.GTL
│   ├── dual_sensor_breakout.GBL
│   ├── dual_sensor_breakout.GTO
│   ├── dual_sensor_breakout.GTS
│   ├── dual_sensor_breakout.GBS
│   └── dual_sensor_breakout.DRL
├── bom/
│   └── bom.csv
└── README.md

Bill of Materials

Pin Header Pinout

Skills Demonstrated

• I2C bus design with multi-device address management
• MEMS sensor layout (BME280, MPU6050) and decoupling strategy
• LDO regulator circuit design
• Solder jumper address select implementation
• Compact mixed-signal PCB layout on 2 layers
• KiCad DRC and Gerber export

Use Cases

• IoT weather stations
• Drone / quadcopter flight controller peripherals
• Wearable motion and environment tracking
• Robot orientation sensing
• Industrial condition monitoring

Project Status

About the Designer

Self-taught PCB designer specializing in KiCad — IoT, embedded systems, and industrial control boards. Available for freelance PCB design work: schematic capture, layout, DRC review, and Gerber preparation.

🔗 GitHub: [Abhi90808] 📧 [kvabhishek908@gmail.com]