Features

2.4 V to 3.6 V single power supply operation

± 2 g/± 6 g users can choose a full marker

Low power consumption

[ 123] The proportion of output voltage, offset and sensitivity to the power supply voltage

Factory fine -tuning device sensitivity and offset

Embedded self -inspection

conforms to ROHS/ECOPACK #174; Standard

High impact survival ability (10000 g)

Instructions

LIS344ALH is a ultra -compact consumer low -power three -axis acceleration meter includes sensing elements and The IC interface can obtain information elements from the induction and to the outside world. Sensing components can detect acceleration, and use the production inertial craft silicon sensor and actuator developed by special ST companies. IC interface uses ST manufacturing patent CMOS process integration. Special circuit adjustment to better match the characteristics of sensor element. Lis344ALH has a dynamic user optional scale ± 2 g/± 6 g, which can measure the maximum bandwidth of all shafts of acceleration 1.8 kHz. This device bandwidth can be used by external capacitors. Self -test capabilities allow users to check the system. LIS344ALH can be used for land grid packaging (LGA). It guarantees that the extended temperature range is -40 ° C to+85 ° C. LIS344ALH belongs to the product series suitable for multiple applications:

- Mobile terminal

- Game and virtual reality input device

- Anti -theft system and inertia navigation

- Equipment and robot.

Mechanical and electrical specifications

Mechanical characteristics

Table 3. Mechanical characteristics@VDD u003d 3.3 V, T u003d 25 ° C, unless there is another instructions (1)

1. The product calibration of the product is 3.3V. The working power range is 2.4V to 3.6V. VOFF, SO, and VT parameters will change with the power supply voltage.

2. Do not guarantee typical specifications.

3. Merit measurement guarantee by chip -level testing and initial offset and sensitivity.

4. Zero level and sensitivity are basically proportional to the power supply voltage of the calibration level ± 8%.

5. Design guarantee.

6. Contribution to the output output of the inclination/acceleration of any vertical axis.

7. ""Self-check output voltage change"" is defined as VOUT (vst u003d logic1) -Vout (vst u003d logic0).

8. ""Self -check output voltage changes""The change of the power supply voltage changes.

9. When the full marker is set to ± 6 g, the"" self -inspection output voltage change ""is one -third of the specified value when ± 2 g. 123]

10. The minimum resonance frequency fres u003d 1.8 kHz. Sensor bandwidth u003d 1/(2*π*110k *CLOAD), CLOAD GT; 1 nf.

123] Table 4. vdd u003d 3.3V, T u003d 25 ° C's electrical characteristics, unless there is another instructions (1)

1. V.

2. Do not guarantee typical specifications.

3. Minimum resonance frequency fres u003d 1.8 kHz. Device bandwidth u003d 1/(2*π*110 k *CLOAD),*CLOAD),*CLOAD),*CLOAD),*CLOAD),*CLOAD),*CLOAD),*CLOAD), CLOAD GT; 1 NF.

Absolutely maximum rated value

The stress that is higher than ""absolute maximum rated value"" may cause permanent damage to the device. This is just a stress rated value and equipment in these pressures The functional operation conditions below are not implicit. Long -term exposure to the highest rating conditions may affect the reliability of the device

This is a mechanical impact sensitive device. Improper operation will cause the operation. Permanent damage parts damage. This is a static sensitive device. Improper operation will be part

terms

The sensitivity describes the gain of the sensor, which can be accelerated to it by applying 1G. Because the sensor can be accelerated. Because the sensor You can measure the DC acceleration, so you can write down the output value by pointing down the interested shaft to the center of the earth, the rotating sensor 180 degrees (pointing to the sky) and recording the output value again, so as to apply the ± 1G sensor acceleration. From a smaller output value Subtracting a large output value and dividing the result with 2 to get the actual sensitivity of the sensor. This value changes a large slight ultra -temperature (seeing sensitivity with temperature changes). Tolerance describes the sensitive range sensor of a large number of people. 0-G level description The actual output signal when there is no acceleration. In a stable state, the measured value of the X-axis and Y axis on the horizontal surface is 0G and 0GZ axis, respectively. The measurement value is 1G. Ideally, the output is suitable for 3.3V power supply VDD/2 u003d 1650 millivolt. . MEMS sensor with accurate displacement is the result of the pressure on the sensor to a certain extent. Therefore, the sensor may be installed on the printing circuit board or exposed, and the offset may change slightly. The offset changes with the temperature with the temperatureDuring the period, it was very stable. Zero G -Class tolerance describes the zero G -grade range of a set of sensors. Self -inspection allows the mechanical and electrical parts of the sensor to allow the earthquake to move the quality of the seismic through electrostatic test force. The self -inspection function is connected to the GND under the following cases. When the ST sales department is at VDD, the driving force will be applied to a certain input acceleration. In this case, the voltage changes of the DC level in the sensor output and the choice of the selected scale and the power supply voltage that depends on the sensitivity of the device. When ST activation, the acceleration is the acceleration level generated by the device and the sensor is used to pass the electrostatic test force. If the amplitude specified in the output signal in Table 3, the sensor works normally and the parameters of the interface chip are within the specified specification range. The output impedance describes the resistance within each channel output stage. This resistor is a part of the filter of at least 1NF external capacitors and internal capacitors. Due to the high resistance level, only small and cheap external capacitors need to generate low -rotation frequencies. In an ADC interface, it is important to use a high input impedance input circuit to avoid measurement errors. Note that the minimum load capacitor forms a close sensor. Generally speaking, the minimum bandwidth of specific applications should be selected to obtain the best result

function

LIS344ALH is a super small low -power analog output three -axis motor acceleration meter and encapsulated in LGA Packaging. The entire device includes an inductive device component and IC interface, which can obtain information from the sensing element and provide analog signal to the outside world.

Sensing components

Patent process is used to make surface micro -mechanical acceleration meters. This technology can realize several points on the suspended silicon structure substrate called anchor point and can move freely in the direction of sensing. In order to be compatible with traditional packaging technology, a lid is placed on the top of the sensor element to avoid packaging in plastic. When the acceleration is applied to the sensor, the verification quality is from its nominal mass displacement position, resulting in unbalanced capacitors. This imbalance is the measured veins that are measured using charge points to respond to applied to the sensor capacitor. In steady state, the nominal value of the capacitor is a small power factor. When the acceleration is applied, the maximum change of the capacitance load is within the FF range.

IC interface

The entire signal processing adopts a full differential structure, and the final level converts the differential signal to a single -end signal world compatible with external signals. The first level is a low -noise capacitor amplifier, which realizes a related dual -at its output sample (CDS) to eliminate offset and 1/F noise. The generated signal is then sent to three different S AMP; AMP; H, one each channel, open to the public. All analog parameters (output offset voltage and sensitivity) and voltage supply. Increase or reduce voltage supply, sensitivity and offset increase linearity linearia. This function can cancel the voltage supply with the modulus number conversion chain.

Factory calibration

IC interfaces have performed sensitivity (SO) and zero G level (VOFF) calibration in the factory. Millet value is stored inside the device through a non -easy -sex structure. After the device is turned on at any time, the fine -tuning parameter is downloaded to the register during the normal operation period. This allows users to calibrate without further calibration.

Power supply -coupled capacitor (100 NF ceramic or polyester+10 μF aluminum) should be as close to the device as possible (general design convention). LIS344ALH allows to use external capacitors. The proposed frequency range is from DC to 1.8 kilo. In particular, a capacitor is added at the output VOUTX, VOUTY, and VOUTZ pin to achieve low -pass filtering anti -aliasing and noise reduction. In this case, the filter is:

The equation of the external filter dead frequency can be simplified as follows:

The tolerance of the internal resistor usually changes in its standard value range ± 20%110 k ;;;; As a result, the deadline will change accordingly. The minimum capacitor is 1Nf requires CLOAD (x, y, z).