1/9 LIS2L02AQ november 2004 1 features 2.4v to 5.25v single supply operation 0.5mg resolution over 100hz bw 2g/6g user selectable full-scale output voltage, offset and sensitivity ratiometric to the supply voltage factory trimmed device sensitivity and offset embedded self test high shock survivability 2description the LIS2L02AQ is a dual-axis linear accelerometer that includes a sensing element and an ic interface able to take the information from the sensing element and to provide an analog signal to the external world. the sensing element, capable to detect the acceler- ation, is manufactured using a dedicated process called thelma (thick epi-poly layer for microactu- ators and accelerometers) developed by st to pro- duce inertial sensors and actuators in silicon. the ic interface instead is manufactured using a cmos process that allows high level of integration to design a dedicated circuit which is trimmed to better match the sensing element characteristics. the LIS2L02AQ has a user selectable full scale of 2g, 6g and it is capable of measuring accelerations over a maximum bandwidth of 4.0 khz for both the x and y axis. the device bandwidth may be reduced by using external capacitances. a self-test capability al- lows the user to check the functioning of the system. the LIS2L02AQ is available in plastic smd package and it is specified over a temperature range extend- ing from -40c to +85c. the LIS2L02AQ belongs to a family of products suit- able for a variety of applications: ? motion activated functions in mobile terminals ? gaming and virtual reality input devices ? virtual reality input devices ? antitheft systems and inertial navigation ? appliance control and robotics inertial sensor: 2axis - 2g/6g linear accelerometer figure 2. block diagram demux s/h charge amplifier s/h mux s1x s1y s2x s2y voutx vouty routx routy rot voltage & current reference trimming circuit & clock & phase generator test interface fi gure 1. p ac k age table 1. order codes part number package LIS2L02AQ qfn-44 qfn-44 rev. 3 obsolete product(s) - obsolete product(s)
LIS2L02AQ 2/9 figure 3. pin description figure 4. pin connection (top view ) n pin function 1 to 3 nc internally not connected 4 gnd 0v supply 5 vdd power supply 6 vouty output voltage 7 st self test (logic 0: normal mode; logic 1: self-test) 8 voutx output voltage 9-13 nc internally not connected 14 pd power down (logic 0: normal mode; logic 1: power-down mode) 15 nc internally not connected 16 fs full scale selection (logic 0: 2g full-scale; logic 1: 6g full-scale) 17-18 reserved leave unconnected 19 nc internally not connected 20 reserved leave unconnected 21 nc internally not connected 22-23 reserved leave unconnected 24-25 nc internally not connected 26 reserved connect to vdd or gnd 27 reserved leave unconnected or connect to vdd 28 reserved leave unconnected or connect to gnd 29-44 nc internally not connected direction of the detectable accelerations y 1 x nc nc nc gnd vdd vouty st voutx nc nc nc nc nc nc nc nc reserved reserved reserved nc nc reserved nc nc pd nc fs reserved reserved reserved reserved nc reserved nc nc nc nc nc nc nc nc nc nc nc LIS2L02AQ obsolete product(s) - obsolete product(s)
3/9 LIS2L02AQ table 2. electrical characteristics (temperature range -40c to +85c) all the para meters are specified @ vdd =3.3v, t=25c unless otherwise noted symbol parameter test condition min. typ. 1 max. unit vdd supply voltage 2.4 3.3 5.25 v idd supply current mean value pd pin connected to gnd 0.85 1.5 ma iddpdn supply current in power down mode rms value pd pin connected to vdd 25 a voff zero-g level 2 t = 25c vdd/2-10% vdd/2 vdd/2+10% v offdr zero-g level vs temperature delta from +25c 1.5 mg/c ar acceleration range 3 fs pin connected to gnd 1.8 2.0 g fs pin connected to vdd 5.4 6.0 g so sensitivity 2 full-scale = 2g vdd/5?10% vdd/5 vdd/5+10% v/g full-scale = 6g vdd/15?10% vdd/15 vdd/15+10% v/g sodr sensitivity drift vs temperature delta from +25c 0.01 %/c nl non linearity 4 best fit straight line full-scale = 2g x, y axis 0.3 1.5 % fs crossax cross-axis 5 2 4% fuc sensing element resonant frequency 6 x, y axis 3.2 4.0 4.8 khz an acceleration noise density vdd=3.3v; full-scale = 2g 50 g/ vt self test output voltage delta change 7,8,9 t = 25c vdd=3.3v full-scale = 2g x axis -20 40 mv t = 25c vdd=3.3v full-scale = 2g y axis 20 -40 mv vst self test input logic 0 level 0 0.8 v logic 1 level 2.2 vdd v rout output impedance 80 110 140 k ? hz obsolete product(s) - obsolete product(s)
LIS2L02AQ 4/9 notes: 1. typical specifications are not guaranteed 2. offset and sensitivity are essentially ratiometric to supply voltage 3. guaranteed by wafer level test and measurement of initial offset and sensitivity 4. guaranteed by design through measurements done up to 1g 5. contribution to the measuring output of the inclination/acceleration along the perpendicular axis 6. guaranteed by design 7. self test ?output voltage delta change? is defined as vout (vst=logic1) -vout (vst=logic0) 8. self test ?output voltage delta change? varies cubically with supply voltage 9. when full-scale is set to 6g, self-test ?output delta change? is one third of the specified value 10.bandwidth=1/(2* *110k ? *cload) absolute maximum rating stresses above those listed as ?absolute maximum ratings? may cause permanent damage to the device. this is a stress rating only and functional operation of the device under these conditions is not implied. exposure to maximum rating conditions for extended periods may affect device reliability. table 3. absolute maximum rating cload capacitive load drive 10 320 pf ton turn-on time at exit from power down mode cload in f 550*cload +0.3 ms symbol ratings maximum value unit vdd supply voltage -0.3 to 7 v vin input voltage on any control pin (fs, pd, st) -0.3 to vdd +0.3 v a pow acceleration (any axis, powered, vdd=3.3v) 3000g for 0.5 ms 10000g for 0.1 ms a unp acceleration (any axis, unpowered) 3000g for 0.5 ms 10000g for 0.1 ms t op operating temperature range -40 to +85 c t stg storage temperature range -40 to +105 c esd electrostatic discharge protection 2kv hbm table 2. electrical characteristics (continued) (temperature range -40c to +85c) all the para meters are specified @ vdd =3.3v, t=25c unless otherwise noted symbol parameter test condition min. typ. 1 max. unit obsolete product(s) - obsolete product(s)
5/9 LIS2L02AQ 3 functionality the LIS2L02AQ is a low-cost, low-power, analog output dual-axis linear accelerometer packaged in qfn pack- age. the complete device includes a sensing element and an ic interface able to take the information from the sensing element and to provide an analog signal to the external world. 3.1 sensing element the thelma process is utilized to create a surface micro-machined accelerometer. the technology allows to carry out suspended silicon structures which are attached to the substrate in a few points called anchors and free to move on a plane parallel to the substrate itself. to be compatible with the traditional packaging tech- niques a cap is placed on top of the sensing element to avoid blocking the moving parts during the molding phase. the equivalent circuit for the sensing element is shown in the figure below; when a linear acceleration is applied, the proof mass displaces from its nominal position, causing an imbalance in the capacitive half-bridge. this im- balance is measured using charge integration in response to a voltage pulse applied to the sense capacitor. figure 5. equivalent electrical circuit rot c s1y c s2y c ps1 c ps2 c pr r s2 r s1 r r s1x s2x c s1z c s2z c ps1 c ps2 c pr r s2 r s1 r r s1y s2y obsolete product(s) - obsolete product(s)
LIS2L02AQ 6/9 the nominal value of the capacitors, at steady state, is few pf and when an acceleration is applied the maximum variation of the capacitive load is few hundredths of pf. 3.2 ic interface the complete signal processing uses a fully differential structure, while the final stage converts the differential signal into a single-ended one to be compatible with the external world. 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 produced signal is then sent to two different s&hs, one for each channel, and made available to the outside. the low noise input amplifier operates at 200 khz while the two s&hs operate at a sampling frequency of 66 khz. this allows a large oversampling ratio, which leads to in-band noise reduction and to an accurate output waveform. all the analog parameters (output offset voltage and sensitivity) are ratiometric to the voltage supply. increasing or decreasing the voltage supply, the sensitivity and the offset will increase or decrease linearly. the feature provides the cancellation of the error related to the voltage supply along an analog to digital conversion chain. 3.3 factory calibration the ic interface is factory calibrated to provide to the final user a device ready to operate. the trimming values are stored inside the device by a non volatile structure. any time the device is turned on, the trimming parameters are downloaded into the regist ers to be employed during the normal operation thus allowing the final user to utilize the device without any need for further calibration. obsolete product(s) - obsolete product(s)
7/9 LIS2L02AQ 4 package information figure 6. qfn-44 mechanical data & package dimensions outline and mechanical data dim. mm inch min. typ. max. min. typ. max. a 1.70 1.80 1.90 0.067 0.071 0.075 a1 0.19 0.21 0.007 0.008 b 0.20 0.25 0.30 0.008 0.01 0.012 d 7.0 0.276 e 7.0 0.276 e 0.50 0.020 j 5.04 5.24 0.198 0.206 k 5.04 5.24 0.198 0.206 l 0.38 0.48 0.58 0.015 0.019 0.023 p 45 ref 45 ref qfn-44 (7x7x1.8mm) q uad f lat p ackage n o lead g m m detail "n" 34 44 11 1 n 22 12 23 33 44 1 detail g seating plane obsolete product(s) - obsolete product(s)
LIS2L02AQ 8/9 table 4. revision history date revision description of changes january 2004 1 first issue february 2004 2 values of some parameters have been changed in electrical characteristics table. november 2004 3 changed the maturity from product preview to final. modified/added some values in the table 2 electrical characteristics. obsolete product(s) - obsolete product(s)
information furnished is believed to be accurate and reliable. however, stmicroelectronics assumes no responsibility for the co nsequences of use of such information nor for any infringement of patents or other rights of third parties which may result from its use. no license is granted by implication or otherwise under any patent or patent rights of st microelectronics. specifications mentioned in this publicati on are subject to change without notice. this publication supersedes and replaces all information previously supplied. stmicroelectronics prod ucts are not authorized for use as critical components in life support devices or systems without express written approval of stmicroelectro nics. the st logo is a registered trademark of stmicroelectronics. all other names are the property of their respective owners ? 2004 stmicroelectronics - all rights reserved stmicroelectronics group of companies australia - belgium - brazil - canada - china - czech republic - finland - france - germany - hong kong - india - israel - ital y - japan - malaysia - malta - morocco - singapore - spain - sweden - switzerland - united kingdom - united states of america www.st.com 9/9 LIS2L02AQ obsolete product(s) - obsolete product(s)
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