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5 0/s yaw rate g yro ADXRS624 rev. 0 information furnished by analog devices is believed to be accurate and reliable. however, no responsibility is assumed by analog devices for its use, nor for any infringements of patents or other rights of third parties that may result from its use. specifications subject to change without notice. no lice nse is granted by implication or otherwise under any patent or patent rights of analog devices. trademarks and registered trademarks are the property of their respective owners. one technology way, p.o. box 9106, norwood, ma 02062 - 9106, u.s.a. tel: 781. 329.4700 www.analog.com fax: 781.461.3113 ? 2010 analog devices, inc. all rights reserved. f eatures complete rate gyroscope on a single chip z- axis (yaw rate) response high vibration rejection over wide frequency 2000 g powered shock survivability ratiometric to referenced supply 5 v single - supply operation 105 c operation self - test on digital c ommand ultrasmall and light (<0.15 cc, <0.5 gram) temperature sensor output rohs c ompliant qualified for automotive applications a pplications navigation systems inertial measurement units platform stabilization robotics g eneral d escription t he adxrs 624 is a complete angular rate sensor (gyr oscope) that uses the analog devices, inc. , surface - micromachining process to create a functionally complete and low cost angular rate se nsor integrated with all required electronics on one chip. the manufacturing technique for this device is the same high vo l ume bi mos process used for high reliability automotive airbag accelerometers. the output signal, rateout (1b, 2a), is a voltage proportional to angular rate about the axis normal to t he top surface of the package. t he output is ratiometric with respect to a provided reference supply. a single external resistor between sumj and rateout can be used to lower the scale factor. an external capacitor set s the bandwidth. other external capacitors are required for operation. a temperature output is pr o vided for compensation techniques. two digital self - test inputs electromechanically excite the sensor to test proper operation of both the sensor and the signal conditioning circuits. the adxrs 624 is available in a 7 mm 7 mm 3 mm bga c hip scale package. f unctional b lock d iagram v dd agnd pgnd av cc st2 st1 temp v ratio cp1 cp2 cp3 cp4 cp5 sumj rateout demod 200k ? 5% 22nf 100nf 22nf 100nf 100nf 100nf drive amp mechanical sensor charge pump and voltage regulator c out +5v +5v +5v (adc ref) ac amp vga 25k? at 25c ADXRS624 25k? self-test 08999-001 figure 1 . adxrs 624 block diagram ADXRS624
ADXRS624 rev. 0 | page 2 of 12 table of contents features .............................................................................................. 1 applications ....................................................................................... 1 general description ......................................................................... 1 functional block diagram .............................................................. 1 revision history ............................................................................... 2 specifications ..................................................................................... 3 absolute maximum ratings ............................................................ 4 rate - sensitive axis ....................................................................... 4 esd caution .................................................................................. 4 pin configuration and function descriptions ............................. 5 typical performance characteristics ............................................. 6 theory of operation .........................................................................9 setting bandwidth .........................................................................9 temperature output and calibration .........................................9 calibrated performance ................................................................9 ADXRS624 and sup ply ratiometricity ......................................9 null adjustment ......................................................................... 10 self - test function ...................................................................... 10 co ntinuous self - te st .................................................................. 10 outline dimensions ....................................................................... 11 ordering guide .......................................................................... 11 au tomotive products ................................................................. 11 r evision h istory 4/10 revision 0: initial version
ADXRS624 rev. 0 | page 3 of 12 specifications all minimum and maximu m specifications are guaranteed; t ypical specifications are not guaranteed. at t a = ? 40 c to +105 c, v s = av cc = v dd = 5 v, v ratio = av cc , a ngular r ate = 0/s, b andwidth = 80 hz (c out = 0.01 f), i out = 100 a, 1 g , unless otherwise noted. table 1. parameter conditions adxrs 624bbg z unit min typ max sensitivity (ratiometric ) 1 clockwise rotation is positive output measurement range 2 full - scale range over specifications range 50 75 /s ec initial and over t emperature 22.5 25 27.5 mv//s ec temperature drift 3 3 % nonlinearity best fit straight line 0.1 % of fs null (r atiome tric ) 1 null ? 40c to +105c 2.5 v linear acceleration effect any axis 0.1 /s ec/ g noise performance rate noise density t a = 25 c 0.04 /s ec/ hz frequency response bandwidth 4 1 1000 hz sensor resonant frequency 14.5 khz self - test (r atiometri c) 1 st1 r ate - out response st1 pin from logic 0 to logic 1 ?1.9 v st2 r ate - out response st2 pin from logic 0 to logic 1 1.9 v logic 1 input voltage 0.8 v ratio v logic 0 input voltage 0.2 v ratio v i nput impedance to common 50 k? temperature sensor (r atiometric ) 1 v out at 25c load = 10 0 m? 2.35 2.5 2.65 v scale factor 5 at 25c, v ratio = 5 v 9 mv/ c load to v s 25 k load to common 25 k turn- on ti me power on to ?/s ec of final 50 ms output drive capability current drive for rated specifications 200 a capacitive load drive 1000 pf power supply operating voltage (v s ) 4.75 5.00 5.25 v v ratio input 3 v s v supply current 3.5 5.0 ma temperature range specified performance C40 +105 c 1 parameter is linearly ratio metric with v rat io . 2 the maximum range possible, including output swing range, initial offset, sensitivity, offset drift, and sensitivity drift at 5 v supplies. 3 from + 25c to ?40c or from + 25c to + 105c. 4 adjusted by the external c apacitor , cout. 5 for a change in temperature from 25 c to 26c. v temp is ratiometric to v ratio . see the temperature output and calibration section for more details.
ADXRS624 rev. 0 | page 4 of 12 absolute maximum rat ings table 2. parameter rating acceleration (any axis, 0.5 ms) unpowered 2000 g powered 2000 g v dd, av cc C0.3 v to +6.0 v v ratio av cc output short - circuit duration (any pin to common) indefinite operating temperature range C 55c to +125c storage temperature C 65c to +150c stresses above those listed under the absolute maximum ra t ings may cause permanent damage to the device. this is a stress rating only; functional operation of the device at these or any other conditions above those indicated in the operational sec tion of this specification is not implied. exposure to absolute maximum rating conditions for extended periods may affect device reliability. drops onto hard surfaces can cause shocks of greater than 2000 g and can exceed the absolute maximum rating of the device. exercise care during handling to avoid damage. rate - sensitive axis th e adxrs 624 is a z - axis rate - sensin g d evice (also called a yaw rate - sensing device). it produces a positive going output voltage for clockwise rotation about the axis normal to the package top, that is , clockwise when looking down at the package lid. rate axis longitudinal axis lateral axis + a b c d g 1 7 e f a1 rate out rate in 4.75v 0.25v v cc = 5v v ratio /2 gnd 08999-002 figure 2 . rat eout signal increases with clockwise rotation esd caution
ADXRS624 rev. 0 | page 5 of 12 pin configuration and function descripti ons ` pgnd st1 st2 temp agnd v ratio nc sumj rateout av cc cp2 cp1 cp4 cp3 cp5 v dd g f e d c b a 7 6 5 4 3 2 1 08999-003 figure 3 . pin configuration table 3. pin function descriptions pin no. mnemonic description 6d, 7d cp5 hv filter capacitor (0.1 f). 6a, 7b cp4 charge pump capacitor (22 nf). 6c, 7c cp3 charge pump capacitor (22 nf). 5a, 5b cp1 charge pump capacitor (22 nf). 4a, 4b cp2 charge pump capacitor (22 nf). 3a, 3b av cc positive analog supply. 1b, 2a rateout rate signal output. 1c, 2c sumj output amp summing junction. 1d, 2d nc no connect. 1e, 2e v ratio reference supply for ratiometric output. 1f, 2g agnd analog supply return. 3f, 3g temp temperature voltage output. 4f, 4g st2 self - test for sensor 2. 5f, 5g st1 self - test for sen sor 1. 6g, 7f pgnd charge pump supply return. 6e, 7e v dd positive charge pump supply.
ADXRS624 rev. 0 | page 6 of 12 typical performance characteristics n > 1000 for all typical performance plots, unless otherwise noted . rateout (v) percent of population (%) 35 30 25 20 15 10 5 0 1.6 1.7 1.8 1.9 2.0 2.1 2.2 2.3 2.4 2.5 2.6 2.7 2.8 2.9 3.0 3.1 3.2 3.3 3.4 08999-004 figure 4 . null output at 25c ( v r atio = 5 v) 0 5 10 15 20 25 30 35 ?0.30 ?0.25 ?0.20 ?0.15 ?0.10 ?0.05 0 0.05 0.10 0.15 0.20 0.25 0.30 percent of popul a tion (%) ra teout tempco (/sec/c) 08999-005 figure 5. null drift o ver temperature ( v ratio = 5 v) 0 5 10 15 20 25 30 24.00 24.25 24.50 24.75 25.00 25.25 25.50 25.75 26.00 26.25 26.50 26.75 27.00 27.25 27.50 percent of popul a tion (%) sensitivity (mv//sec) 08999-006 figure 6. sensitivity at 25c (v ratio = 5 v) 0 5 10 15 20 25 30 35 40 45 ?10 ?8 ?6 ?4 ?2 0 2 4 6 8 10 percent of popul a tion (%) sensitivity drift (%) 08999-007 figure 7. sensitivity drift o ver t emperature 0 5 10 15 20 25 30 35 40 ?2.10 ?2.05 ?2.00 ?1.95 ?1.90 ?1.85 ?1.80 ?1.75 ?1.70 ?1.65 ?1.60 ?1.55 ?1.50 ?1.45 ?1.40 ?1.35 ?1.30 percent of popul a tion (%) st1 (v) 08999-008 figure 8. st1 output c hange at 25c (v ratio = 5 v) 0 5 10 15 20 25 30 35 40 1.30 1.35 1.40 1.45 1.50 1.55 1.60 1.65 1.70 1.75 1.80 1.85 1.90 1.95 2.00 2.05 2.10 percent of popul a tion (%) st2 (v) 08999-009 figure 9. st2 output c hange at 25c (v ratio = 5 v)
ADXRS624 rev. 0 | page 7 of 12 0 5 10 15 20 25 30 50 54 58 62 66 70 74 78 82 86 90 94 98 per c ent of popul a tion (%) measurement range (/sec) 08999-010 figure 10 . measurement range 2.5 ?2.5 ?40 120 temperature (oc) self-test (v) 2.0 1.5 1.0 0.5 0 ?0.5 ?1.0 ?1.5 ?2.0 ?20 0 20 40 60 80 100 08999-011 figure 11 . typical self - test change o ver temperature 30 0 (ma) percent of population (%) 25 20 15 10 5 3.7 3.8 3.9 4.0 4.1 4.2 4.3 4.4 4.5 2.5 2.6 2.7 2.8 2.9 3.0 3.1 3.2 3. 3 3.4 3.5 3.6 08999-012 figure 12 . current consumption at 25c (v ratio = 5 v) 40 35 30 25 0 5 10 15 20 2.40 2.42 2.44 2.46 2.48 2.50 2.54 2.56 2.58 2.60 2.52 percent of population (%) v temp output (v) 08999-013 figure 13 . v temp output at 25c (v ratio = 5 v) 3.3 3.1 2.9 2.7 1.5 2.1 1.9 1.7 2.3 2.5 ?40 ?20 0 20 40 60 100 120 80 v temp output (v) temperature (c) 256 parts 08999-014 figure 14 . v temp output o ver temperatu re (v ratio = 5 v) 60 50 30 40 10 20 ?20 ?10 0 750 770 810 830 850 790 g or /s time (ms) y ref x +45 ?45 08999-015 figure 15 . g and g g sensitivity for a 50 g , 10 ms pulse
ADXRS624 rev. 0 | page 8 of 12 0 0. 2 0. 4 0. 6 0. 8 1.0 1. 2 1. 6 2.0 1. 4 1. 8 10 0 1k 10k peak rateout ( /s) frequency (hz) la titude longitude ra te 08999-016 figure 16 . typical response to 10 g sinusoidal vibration (sensor bandwidth = 2 khz) 400 300 200 100 0 ?100 ?200 ?300 ?400 0 250 150 100 200 50 (ms) (/s) dut1 offset by +200/s dut2 offset by ?200/s 08999-017 figure 17 . typical high g (2500 g ) shock response (sensor bandwidth = 40 hz) 1 0.1 0.01 0.001 0.01 0.1 100k 10k 1k 100 10 1 average time (seconds) (/s rms) 08999-018 figure 18 . typical root allan deviation at 25c vs. averaging time 0.10 ?0.05 0 0.05 ?0.10 0 140 120 100 80 60 40 20 time (hours) (/s) 08999-019 figure 19 . typical shift in 90 s ec null averages accumulated o ver 140 h ours 0.10 0.05 0 ?0.05 ?0.10 0 3600 1800 1200 3000 2400 600 time (seconds) (/s) 08999-020 figure 20 . typical shift in short term null (bandwidth = 1 hz) 0.1 0.001 0.01 0.0001 10 100k 1k 100 (hz) (/s/ hz rms) 10k 08999-021 figure 21 . typical noise spectral density (bandwidth = 40 hz)
ADXRS624 rev. 0 | page 9 of 12 theory of operation the adxrs 624 operates on the principle of a resonator gyro. two polysilicon sensing structures each contain a dither fra me that is electrostatically driven to resonance , producing the necessary velocity element to produce a coriolis force during angular rate. at two of the outer extremes of each frame, or thogonal to the dither motion, are movable fingers that are placed between fixed pickoff fingers to form a capacitive pickoff structure that senses coriolis motion. the resulting signal is fed to a series of gain and demodulation stages tha t produce the electrical rate signal output. the dual - sensor design rejects external g forces and vibration. fabricating the sensor with the signal conditioning electronics preserves signal integrity in noisy env i ronments. the electrostatic resonator requires 18 v to 20 v for operation. because only 5 v are typically available in most applications, a charge pump is included on - chip. if an external 18 v to 20 v supply is avail able, the two capacitors on cp1 through cp4 can be omi t ted , and this supply can be connected to cp5 (pin 6d, pin 7d). note that cp5 should not be grounded when power is applied to the adxrs 624. although no damage occur s, under certain conditions the charge pump may fail to start up after the ground is removed without first removing power from the adxrs 624 . setting bandwidth external c apacitor c out is used in combination with the on - chip r out resistor to create a low - pass filter to limit the bandwidth of the adxrs 624 rate response. the C 3 db fr e quency set by r out and c out is ( ) out out out cr f = 2 1 and can be well controlled because r out is trimmed du r ing manufacture to be 200 k ? 1%. any external resistor applied be tween the rateout pin (1b, 2a) and sumj pin (1c, 2c) result s in ( ) ( ) ext ext out r r r + = k 200 k 200 in general, an additional hardware o r software filter is added to attenuate high frequency noise arising from demodulation spikes at the gyros 14 khz resonant frequency (the noise spikes at 14 khz can be clearly seen in the power spectral density curve shown in fi gure 21 ). typically, this additional filters corner fre quency is set to greater than 5 the required band - width to preserve good phase response. figure 22 shows the effect of adding a 250 hz filter to the output of an adxrs 62 4 set to 40 hz bandwidth (as shown in figure 21 ). high frequency demodulation artifacts are attenuated by approximately 18 db . 0.1 0.01 0.000001 0.00001 0.0001 0.001 10 100k 1k 100 (hz) (/s/ hz rms) 10k 08999-022 figure 22 . noise spectral density with additional 250 hz filter temperature output and calibration it is common practice to temperature - calibrate gyros to improve their overall accuracy. the adxrs 624 has a temper a ture proportional voltage output that provides input to such a cal i bration method. the temperature sensor structure is shown in figure 23 . the temperature o utput is characteristically non linear, and any load resistance connected to the temp output results in decreasing the temp output and temperature coef ficient. therefore, b uffering the outp ut i s recommended. the voltage at the temp pin (3f, 3g) is nominally 2.5 v at 25c and v ratio = 5 v. t h e temperature coefficient is ~9 mv/c at 25c. although the temp output is highly repeatable, it has only modest absolute accuracy. v ratio r temp r fixed v temp 08999-023 figure 23 . adxrs 624 temperature sensor structure calibrated performan ce using a three - point calibration technique, it is possible to calibrate the null and sensitivity drift of the adxrs 624 to an overall accuracy of nearly 200/hour. an overall accu racy of 40/hour or better is possible using more points. limiting the bandwidth of the device reduces the flat - band noise during the calibration process, improving the measure - ment accuracy at each calibr a tion point. adxrs 624 and supply ratiometr icity th e adxrs 624 rateout and temp signals are ratiometric to the v ratio voltage; that is , the null voltage, rate sensitivity, and temperature outputs are proportional to v ratio . thus, the adxrs 624 is most easily used with a supply - ratiometric adc that results in self - cancellation of errors due to minor supply vari a tions. there is some small error due to non ratiometric
ADXRS624 rev. 0 | page 10 of 12 behavior. typical ratiome t ricity error for null, sensitivity, self - test, and temperature output is o utlined in tabl e 4 . note that v ratio must never be greater than av cc . table 4 . ratiometricity error for various parameters parameter v s = v r atio = 4.75 v v s = v r atio = 5.25 v st1 mean ?0.4% ?0.3% sigma 0.6% 0.6% st2 mean ?0.4% ?0.3% sigma 0.6% 0.6% null mean ?0.04% ?0.02% sigma 0.3% 0.2% sensitivity mean 0.03% 0.1% sigma 0.1% 0.1% v temp mean ?0.3% ?0.5% sigma 0.1% 0.1% null adjustment the nom i nal 2.5 v null is for a symmetrical swing range at rateout (1b, 2a). however, a nonsy mmetrical output swing may be sui t able in some applications. null adjustment is possible by injecting a suitable current to sumj (1c, 2c). note that supply distu r bances may reflect some null instability. digital supply noise should be avoided partic u larly in this case. self - test function the adxrs 624 includes a self - test feature that actuates each of the sensing structures and associated electronics as if subjected to angular rate. the self - test feature is activated by standard logic high levels applied to input st1 (5f, 5g), input st2 (4f, 4g), or both. st1 causes the voltage at rateout to change about ?1.9 v, and st2 causes an opposite change of +1.9 v. t h e self - test response follows the viscosity temperature depen d ence of the package atmosphere, approxima tely 0.25%/c. activating both st1 and st2 simultaneously is not damaging. st1 and st2 are fairly closely matched (5%), but actua t ing both s i multaneously may result in a small apparent null bias shift pro portional to the degree of self - test mismatch. st1 and st2 are activated by applying a voltage of greater than 0.8 v ratio to the st1 and st2 pins. st1 and st2 are deactivated by applying a voltage of less than 0.2 v ratio to the st1 and st2 pin s. the voltage applied to st1 and st2 must never be greater than av cc . continuous self - test the one - chip integration of the adxrs 624 gives it higher reliability than is obtainable with any other high volume manufa c turing method. in addition , it is manufactured under a mature b i mos process with field - proven reliab ility. as an additional failure detection measure, a power - on self - test can be performed. ho w ever, some applications may warrant continuous self - test while sensing rate. details outlining continuous self - test techniques are also available in the an - 768 a pplication n ote.
ADXRS624 rev. 0 | page 11 of 12 outline dimensions a b c d e f g 7 6 5 4 3 top view detail a ball diameter 0.60 0.55 0 .50 0.60 max 0.25 min coplanarity 0.15 2 1 * a1 corner index area 3.20 max 2.50 min * ball a1 identifier is gold p lated and connected to the d/a pad internally via holes. 10-26-2009-b 7.05 6.85 sq 6.70 a1 ball corner bottom view detail a 0.80 bsc 4.80 bsc sq seating plane 3.80 max figure 24 . 32- lead ceramic ball grid array [cbga] (bg- 32 -3 ) dimensions shown in millimeters ordering guide model 1, 2 temperature range package description package o ption adxrs 624w bbg z C 40c to +105c 32- lead ceramic ball grid array (c bga ) bg -32-3 adxrs 624w bbg z- rl C 40c to +105c 32- lead ceramic ball grid array (cbga) bg -32-3 eval -ADXRS624z evaluation board 1 z = rohs compliant part. 2 w = q ualified for a utomotive a pplications. automotive products the ADXRS624wbbgz models are available with controlled manufacturing to support the quality and reliability requirements of automotive applications. note that these automotive models may have specifications that differ from the commercial models; th erefore , designers should review the specifications section of this data sheet carefully. only the automotive grade products shown are available for use in automotive applications. contact your local analog devices accoun t representative for specific product ordering information and to obtain the specific automotive reliability reports for these models.
ADXRS624 rev. 0 | page 12 of 12 notes ? 2010 analog devices, inc. all rights reserved. trademarks and registered trademarks are the property of their respective owners. d08999 -0- 4/10(0)

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