HMC5883 Magnetometer IC Pin Diagram, Circuit and Applications

The HMC5883 is a three axis digital magnetometer IC used to measure the Earth’s magnetic field for electronic compass and navigation applications. It communicates through an I�C interface and is widely used in drones, robotics, smartphones, wearable devices, and navigation systems. This article explains its pin diagram, working principle, circuit, features, and applications.

Key features of HMC5883

• Highly Integrated & Compact: Features 3-axis magnetoresistive (AMR) sensors and an ASIC in a tiny 3.0 x 3.0 x 0.9 mm LCC surface mount package.
• High Resolution & Accuracy: Includes a 12-bit ADC that provides 5 milli-Gauss resolution, enabling precise 1 to 2 degrees compass heading accuracy.
• Wide Magnetic Field Range: Capable of measuring magnetic fields from milli-gauss up to +/- 8 Gauss (Oe).
• Low Power/Voltage Operation: Operates on low voltage (1.6V to 3.3V) with multiple power management modes (Continuous, Single-Measurement, Idle, Sleep, and Off), making it ideal for battery-powered devices.
• Communication Interface: Standard I2C digital interface supporting up to 400 kHz fast mode for easy connection to microcontrollers.
• Built-in Support Circuits: Features automatic degaussing strap drivers (Set/Reset) and offset cancellation, plus a Built-In Self Test for low-cost production functionality testing.
• Algorithm Support: Compatible with software libraries for compassing heading, hard iron/soft iron calibration, and auto-calibration.

HMC5883 Pin Diagram

Here’s a look at the HMC5883 pin diagram:

Pin No.	Pin Name	Type	Function
1	SCL	Digital Input	I²C serial clock input used for communication with the host microcontroller.
2	AVDD	Power	Analog power supply input (typically 2.16 V to 3.6 V). Supplies the analog sensing circuitry.
3	NC	—	No internal connection. Leave unconnected.
4	NC	—	No internal connection.
5	NC	—	No internal connection.
6	NC	—	No internal connection.
7	NC	—	No internal connection.
8	SETP	Analog	Positive terminal for the internal set/reset strap capacitor (C2). Used for magnetic offset calibration and sensor reset.
9	GND	Ground	Ground connection for the analog circuitry.
10	C1	Analog	Reservoir capacitor connection. An external capacitor is connected to this pin for internal charge storage.
11	GND	Ground	Ground connection for the digital/analog circuitry. Connect to PCB ground.
12	SETC	Analog	Negative terminal (driver side) of the set/reset strap capacitor (C2). Used together with SETP.
13	DVDD	Power	Digital power supply input for the I²C interface and digital logic.
14	VREN	Digital Input	Voltage regulator enable. Connect to AVDD for single-supply operation or GND for dual-supply operation.
15	DRDY	Digital Output	Data Ready output. Indicates that new magnetic field measurement data is available in the output registers.
16	SDA	Bidirectional	I²C serial data line used for configuration and reading X, Y, and Z magnetic field data.

Example Use Case Smartphone Digital Compass & Pedestrian Navigation

The HMC5883 is integrated into a smartphone to provide map orientation and digital compass capabilities for pedestrian navigation.

The HMC5883 is connected to the smartphone’s host processor via the two-wire I2C interface. It is powered by the phone’s battery system using a nominal 1.8V digital supply and 2.5V analog supply. Two external capacitors (a 4.7 µF reservoir capacitor and a 0.22 µF set/reset capacitor) are added to the circuit to handle the brief, high-current pulses needed for the built-in sensor degaussing (Set/Reset) strap.

Applications of HMC5883

• Mobile Phones and Smartphones
• Netbooks and Laptops
• Consumer Electronics
• Auto Navigation Systems
• Personal Navigation Devices (PNDs)
• Low cost compassing and magnetometry

Summary

The HMC5883 provides accurate digital magnetic field measurements for orientation and navigation. Its low power consumption makes it suitable for portable embedded systems.