Datasheet

HMC5883L
20 www.honeywell.com
SCALE FACTOR TEMPERATURE COMPENSATION
The built-in self test can also be used to periodically compensate the scaling errors due to temperature variations. A
compensation factor can be found by comparing the self test outputs with the ones obtained at a known temperature. For
example, if the self test output is 400 at room temperature and 300 at the current temperature then a compensation factor
of (400/300) should be applied to all current magnetic readings. A temperature sensor is not required using this method.
Below is an example of a temperature compensation process using positive self test method:
1. If self test measurement at a temperature “when the last magnetic calibration was done”:
X_STP = 400
Y_STP = 410
Z_STP = 420
2. If self test measurement at a different tmperature:
X_STP = 300 (Lower than before)
Y_STP = 310 (Lower than before)
Z_STP = 320 (Lower than before)
Then
X_TempComp = 400/300
Y_TempComp = 410/310
Z_TempComp = 420/320
3. Applying to all new measurements:
X = X * X_TempComp
Y = Y * Y_TempComp
Z = Z * Z_TempComp
Now all 3 axes are temperature compensated, i.e. sensitivity is same as “when the last magnetic calibration was
done”; therefore, the calibration coefficients can be applied without modification.
4. Repeat this process periodically or,for every Δt degrees of temperature change measured, if available.
ORDERING INFORMATION
Ordering Number
Product
HMC5883L-T
HMC5883L-TR
Cut Tape
Tape and Reel 4k pieces/reel
FIND OUT MORE
For more information on Honeywell’s Magnetic Sensors visit us online at www.magneticsensors.com or contact us at
1-800-323-8295 (763-954-2474 internationally).
The application circuits herein constitute typical usage and interface of Honeywell product. Honeywell does not warranty or assume liability of customer-
designed circuits derived from this description or depiction.
Honeywell reserves the right to make changes to improve reliability, function or design. Honeywell does not assume any liability arising out of the
application or use of any product or circuit described herein; neither does it convey any license under its patent rights nor the rights of others.
U.S. Patents 4,441,072, 4,533,872, 4,569,742, 4,681,812, 4,847,584 and 6,529,114 apply to the technology described
Honeywell
12001 Highway 55
Plymouth, MN 55441
Tel: [phone]
www.magneticsensors.com
Form # 900405 Rev E
February 2013
©2010 Honeywell International Inc.