LSM303DLHC Datasheet, PDF (15/43 Pages) STMicroelectronics – Ultra compact high performance e-compass 3D accelerometer and 3D magnetometer module

LSM303DLHC
3
Functionality
Functionality
The LSM303DLHC is a system-in-package featuring a 3D digital linear acceleration and 3D
digital magnetic field detection sensor.
The system includes specific sensing elements and an IC interface capable of measuring
both the linear acceleration and magnetic field applied on it and to provide a signal to the
external world through an I²C serial interface with separated digital output.
The sensing system is manufactured using specialized micromachining processes, while
the IC interfaces are realized using a CMOS technology that allows to design a dedicated
circuit which is trimmed to better match the sensing element characteristics.
The LSM303DLHC features two data-ready signals (RDY) which indicate when a new set of
measured acceleration data and magnetic data are available, therefore simplifying data
synchronization in the digital system that uses the device.
The LSM303DLHC may also be configured to generate a free-fall interrupt signal according
to a programmed acceleration event along the enabled axes.
Linear acceleration operating mode
LSM303DLHC provides two different acceleration operating modes, respectively reported
as “normal mode” and “low-power mode”. While normal mode guarantees high resolution,
low-power mode reduces further the current consumption.
Table 8 summarizes how to select the operating mode.
Table 8. Accelerometer operating mode selection
CTRL_REG1[3] CTRL_REG4[3]
Operating mode
(LPen bit)
(HR bit)
Low-power mode
1
0
Normal mode
0
1
BW
[Hz]
ODR/2
ODR/9
Turn-on time
[ms]
1
7/ODR
3.1
Factory calibration
The IC interface is factory calibrated for linear acceleration sensitivity (LA_So), and linear
acceleration Zero-g level (LA_TyOff).
The trimming values are stored inside the device by a non-volatile memory. Any time the
device is turned on, the trimming parameters are downloaded into the registers to be used
during the normal operation. This allows the user to use the device without further
calibration.
Doc ID 018771 Rev 1
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