LIS352AXTR STMicroelectronics, LIS352AXTR Datasheet - Page 9

• Manufacturer Part Number: LIS352AXTR
• Description: IC ACCELEROMETER 3AXIS 2G 14-LGA
• Manufacturer: STMicroelectronics

Specifications of LIS352AXTR

• Featured Product: STM32 Cortex-M3 Companion Products
• Axis: X, Y, Z
• Acceleration Range: ±2g
• Sensitivity: 0.363 V/g
• Voltage - Supply: 2.16 V ~ 3.6 V
• Output Type: Analog
• Bandwidth: 2kHz
• Interface: IC
• Mounting Type: Surface Mount
• Package / Case: 14-LGA
• Package Type: LGA
• Operating Supply Voltage (min): 2.16V
• Operating Supply Voltage (typ): 3.3V
• Operating Supply Voltage (max): 3.6V
• Operating Temperature (min): -40C
• Operating Temperature (max): 85C
• Operating Temperature Classification: Industrial
• Product Depth (mm): 3mm
• Product Height (mm): 0.92mm
• Product Length (mm): 5mm
• Mounting: Surface Mount
• Pin Count: 14
• Sensing Axis: X, Y, Z
• Acceleration: 2 g
• Supply Voltage (max): 3.6 V
• Supply Voltage (min): 2.16 V
• Supply Current: 0.3 mA
• Maximum Operating Temperature: + 85 C
• Minimum Operating Temperature: - 40 C
• Mounting Style: SMD/SMT
• Shutdown: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 497-8979-2

LIS352AX
4
4.1
4.2
4.3
Functionality
The LIS352AX is a 3-axis ultracompact low-power, analog output linear accelerometer
packaged in a LGA package. The complete device includes a sensing element and an IC
interface capable of taking information from the sensing element providing an analog signal
to the external world.
Sensing element
A proprietary process is used to create a surface micro-machined accelerometer. The
technology allows the creation of suspended silicon structures which are attached to the
substrate at several points called “anchors” and are free to move in the direction of the
sensed acceleration. To be compatible with traditional packaging techniques, a cap is
placed on top of the sensing element to prevent blocking of the moving parts during the
moulding phase of plastic encapsulation.
When an acceleration is applied to the sensor, the proof mass shifts from its nominal
position, causing an imbalance in the capacitive half-bridge. This imbalance is measured
using charge integration in response to a voltage pulse applied to the sense capacitor.
At steady state, the nominal value of the capacitors are a few pF, and when an acceleration
is applied the maximum variation of the capacitive load is in the fF range.
IC interface
The complete signal processing utilizes a fully differential structure, while the final stage
converts the differential signal into a single-ended signal to be compatible with external
applications.
The first stage is a low-noise capacitive amplifier that implements a correlated double
sampling (CDS) at its output to cancel the offset and the 1/f noise. The signal produced is
then sent to three different S&Hs, one for each channel, and made available to the outside.
The device provides an embedded multiplexer to allow the redirection of either the analog
output signals Voutx, Vouty, and Voutz, or of an auxiliary input signal onto a single pin for
operation with a single-channel A/D converter.
All the analog parameters (output offset voltage and sensitivity) are absolute with respect to
the voltage supply. Increasing or decreasing the voltage supply will not cause a change in
the sensitivity and the offset. The feature allows the coupling of the sensor with an ADC,
having a fixed voltage reference independent from Vdd.
Factory calibration
The IC interface is factory calibrated for sensitivity (So) and zero-g level (Voff).
The trimming values are stored inside the device in a non volatile structure. Any time the
device is turned on, the trimming parameters are downloaded into the registers to be
employed during the normal operation. This allows the user to employ the device without
further calibration.
Doc ID 15530 Rev 2
Functionality
9/15