MCP9808 High Accuracy I2C Temperature Sensor Module

MCP9808 High-Accuracy I²C Temperature Sensor Module delivers precise and easy-to-integrate temperature sensing for embedded and IoT projects. Designers use this module for environmental monitoring, thermal management, and calibration tasks where sub-degree accuracy and simple I²C interfacing speed development.

Key Features:

• High Accuracy: Delivers sub-degree temperature accuracy suitable for calibration and control applications.
• I²C Interface: Communicates over the standard two-wire I²C bus with an easily selectable 7-bit address.
• Compact Module: Breakout-ready board exposes power, I²C, and alert pins for fast prototyping.
• High Resolution: Offers fine temperature resolution for precise monitoring and logging.
• Low Power: Operates with low quiescent current and supports shutdown modes to save battery life.
• Alert Output: Provides a programmable thermostat/alert output for interrupt-driven designs.

Technical Specifications:

• Supply Voltage (V_CC): Typically 2.7 V to 5.5 V (check module/supplier datasheet)
• Temperature Range: −40 °C to +125 °C (device-rated range; see datasheet for accuracy vs. temperature)
• Accuracy: ±0.25 °C (typical) in common ambient range; consult datasheet for full temperature-dependent specs
• Resolution: 0.0625 °C (4 fractional bits) selectable/readable via registers
• I²C Speed: Standard and fast-mode I²C compatible (refer to datasheet and module documentation for max clock)
• Addressing: Programmable 7-bit I²C address via module pads or jumpers to allow multiple sensors on one bus
• Alert/Interrupt: Open-drain alert output with programmable thresholds and hysteresis
• Operating Modes: Continuous conversion and low-power shutdown modes

Mechanical Specifications:

• Module Board: PCB breakout with the MCP9808 IC, pull-up resistor footprints, and address pads or jumpers
• Connector Type: 0.1″ (2.54 mm) header pins for VCC, GND, SDA, SCL, ALERT, and ADD (may be unpopulated on some sellers)
• Mounting: Two mounting holes or adhesive pad depending on supplier variant
• Components: On-board decoupling capacitor and optional pull-up resistors for I²C lines

Dimensions:

• Typical Module Size: ~17 mm × ~15 mm (module sizes vary by supplier; confirm mechanical drawing)
• Pin Pitch: 2.54 mm (standard 0.1″ header spacing)

Pinout and Wiring:

• VCC: Connect 2.7–5.5 V supply to this pin. Use stable supply and decoupling capacitor near module.
• GND: Connect to system ground.
• SDA: I²C data line. Use pull-up resistors if not present on the module.
• SCL: I²C clock line. Keep traces short for reliable communication at higher speeds.
• ALERT/INT: Open-drain alert output. Pull up to VCC and wire to MCU interrupt input for threshold-driven events.
• ADD / ADR: Address select pad or jumper. Configure to set the lower bits of the device I²C address when multiple sensors share the bus.
• Wiring note: Place pull-up resistors (typically 2.2k–10k) on SDA and SCL if the module does not include them. Route ground and power traces with adequate width for stable readings.

Datasheet Reference:

• Refer to the Microchip MCP9808 datasheet for full electrical characteristics, temperature accuracy curves, register map, and application circuits. Search the supplier site for “MCP9808 datasheet”.

Applications:

• Environmental Monitoring: Measure ambient temperature in weather stations, greenhouses, and HVAC sensors.
• Thermal Management: Use in power supplies, battery packs, and motor controllers to prevent overheating.
• IoT and Wearables: Provide precise local temperature feedback for connected devices and wearables.
• Calibration and Test: Use as a reference sensor in lab and production test setups.
• Consumer Electronics: Integrate into appliances and thermostats for accurate user-facing temperature control.

Equivalent Models:

• TMP102: Low-power I²C temperature sensor with good accuracy for many designs.
• LM75 / LM75A: Popular I²C temperature sensors with different accuracy and feature sets.
• ADT7420: High-accuracy digital temperature sensor alternative for precision applications.

Package Includes:

• 1 x MCP9808 High-Accuracy I²C Temperature Sensor Module (breakout board)
• Optional: 1 x 6-pin header (may ship unassembled depending on supplier)