View ADXRS623_6953103.PDF datasheet online --- IC-ON-LINE

Datasheet File OCR Text:

150/sec yaw rate gyroscope ADXRS623 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 license 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. features 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 C40c to +105c operation self-test on digital command ultrasmall and light (<0.15 cc, <0.5 gram) temperature sensor output rohs compliant applications inertial measurement units platform stabilization robotics general description the ADXRS623 is a complete angular rate sensor (gyroscope) that uses the analog devices, inc., surface-micromachining process to create a functionally complete and low cost angular rate sensor integrated with all required electronics on one chip. the manufacturing technique for this device is the same high volume bimos process used for high reliability automotive airbag accelerometers. the output signal, rateout (1b, 2a), is a voltage proportional to the angular rate about the axis that is normal to the top surface of the package. the output is ratiometric with respect to a pro- vided reference supply. an external capacitor sets the bandwidth. other external capacitors are required for operation. a temperature output is provided for compensation techniques. two digital self-test inputs electromechanically excite the sensor to test proper operation of both the sensor and the signal con- ditioning circuits. the ADXRS623 is available in a 7 mm 7 mm 3 mm ceramic ball grid array (cbga) package. functional block diagram v dd agnd pgnd av cc st2 st1 temp v ratio cp1 cp2 cp3 cp4 cp5 sumj rateout demod 180k ? 1% 22nf 100nf 22nf 100nf 100nf 100nf drive amp mechanical sensor charge pump and voltage regulator c out +5v +5v +5 v (adc ref) ac amp vga 25k? @ 25c ADXRS623 25k? self-test 08890-001 figure 1.
ADXRS623 rev. 0 | page 2 of 12 table of c ontents 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 ADXRS623 and supply ratiometricity ................................... 10 null adjustment ......................................................................... 10 self- test function ...................................................................... 10 continuous self - te st .................................................................. 10 outline dimensions ....................................................................... 11 ordering guide .......................................................................... 11 r evision h istory 3/10 revision 0: initial version
ADXRS623 rev. 0 | page 3 of 12 specifications all minimum and maximum specifications are guaranteed. typical specifications are not guarant eed. t a = ? 40 c to +105 c, v s = av cc = v dd = 5 v, v ratio = av cc , angular r ate = 0/s ec , b andwidth = 80 hz (c out = 0.01 f), i out = 100 a, 1 g , unless otherwise noted. table 1. parameter test conditions /comments min typ max unit s ensitivity ( ratiometric ) 1 clockwise rotation is positive output measurement range 2 full - scale range over specifications range 1 50 /s ec initial and o ver t emperature 11 .25 12.5 13.75 mv//s ec temperature drift 3 3 % nonlinearity best fit stra ight line 0.1 % of fs null ( ratiometric ) 1 null ? 40c to +105c 2.5 v null drift o ver temperature ?40c to +105c 250 mv linear acceleration effect any axis 0.1 /sec/ g noise performance rate noise density t a = 25c 0.04 /sec/ hz frequency response bandwidth 4 1 3000 hz senso r resonant frequency 14.5 khz self - test ( ratiometric ) 1 st1 rateout response st1 pin from logic 0 to logic 1 ? 500 ?1000 mv st2 rateout response st2 pin from logic 0 to logic 1 500 1000 mv log ic 1 input voltage 0.8 v ratio v logic 0 input voltage 0.2 v ratio v input impedance to common 50 k? temperature sensor ( ratiometric ) 1 v out at 25c load = 100 m ? 2.35 2.5 2.65 v scale f actor 5 at 25c, v ratio = 5 v 9.1 mv/ c load to v s 25 k ? load to common 25 k ? turn - on time power on to ?/sec of final 50 ms output drive capability current drive for rated specifications 200 a capacitive load drive 1000 pf powe r supply operating voltage (v s ) 4.75 5.00 5.25 v vratio input 3 v s v supply current 3.5 5.0 ma temperature range specified performance C 40 +105 c 1 parameter is linearly ratio metric with v ratio . 2 the maximum range possible, incl uding 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 external c apacitor , c out . 5 for a change in temperature from 25c to 26c. v temp is ra tiometric to v ratio . see the temperature output and calibration section for more details.
ADXRS623 rev. 0 | page 4 of 12 absolute maximum rat ings table 2 . parameter rating accel eration (any axis, 0.5 ms) unpowered 2000 g powered 2000 g v dd , av cc C 0.3 v to +6.0 v v ratio av cc output short - circuit duration (any pin to common) indefinite operating temperature range C 40 c to +125c storage temperature range C 65c to +150c s tresses 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 se c tion of th is 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 > 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 623 is a z - axis , rate - sensing device (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 a b c d e f g 1 a1 7 lateral axis longitudinal axis rate out rate in 4.75v 0.25v v cc = 5v v ratio /2 gnd 08890-002 figure 2 . rateout signal increases with clockwise rotation esd caution
ADXRS623 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 nc = no connect 08890-003 figure 3 . pin configurat ion table 3 . pin function descriptions pin no. mnemonic description 6d, 7d cp5 hv filter capacitor (100 n f). 6a, 7b cp4 charge pump capacitor (22 nf). 6c, 7c cp3 charge pump capacitor (22 nf). 5a, 5b cp1 charge pump capacitor (2 2 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 lifier summing junction. 1d, 2d nc no connect. 1e, 2e v ratio reference supply for ratiometric output. 1f, 2 g agnd analog supply return. 3f, 3g temp temperature voltage output. 4f, 4g st2 self- test for sensor 2. 5f, 5g st1 self- test for sensor 1. 6g, 7f pgnd charge pump supply return. 6e, 7e v dd positive charge pump supply.
ADXRS623 rev. 0 | page 6 of 12 typical performance characteris tics n > 1000 for all typical performance plots, unless otherwise noted . 0 2.0 rateout (v) percent of population (%) 25 20 15 10 5 2.1 2.2 2.3 2.4 2.5 2.7 2.9 2.6 2.8 3.0 08890-004 figure 4. null output at 25c ( v ratio = 5 v) 30 35 40 45 0 (/s/c) percent of population (%) 25 20 15 10 5 ?0.5 ?0.4 ?0.3 ?0.2 ?0.1 0 0.1 0.2 0.3 0.4 0.5 08890-005 figure 5. null drift o ver temperature ( v ratio = 5 v) 0 1 1.00 sensitivity (mv//s) percent of population (%) 35 30 25 20 15 10 5 11.50 12.00 12.50 13.00 13.50 1 1.25 11.75 12.25 12.75 13.25 13.75 14.00 08890-006 figure 6. sensitivity at 25c (v ratio = 5 v) 30 0 ?10 percent drift (%) percent of population (%) 25 20 15 10 5 ?8 ?6 ?4 ?2 0 2 4 6 8 10 08890-007 figure 7. sensitivity drift o ver t emperature 45 0 st1 (mv) percent of population (%) 40 35 30 25 20 15 10 5 08890-008 ?1400 ?1300 ?1200 ?1100 ?1000 ?900 ?800 ?700 ?600 ?500 figure 8. st1 output c hange at 25c (v ratio = 5 v) 45 0 st2 (mv) percent of population (%) 40 35 30 25 20 15 10 5 1400 1300 1200 1100 1000 900 800 700 600 500 08890-009 figure 9. st2 output c hang e at 25c (v ratio = 5 v)
ADXRS623 rev. 0 | page 7 of 12 30 0 125 measurement range (/s) percent of population (%) 25 20 15 10 5 135 145 155 165 175 185 195 08890-010 figure 10 . measurement range 1.5 ?1.5 ?40 120 temperature (c) voltage (v) 1.0 0.5 0 ?0.5 ?1.0 ?20 0 st1 st2 20 40 60 80 100 08890-011 figure 11 . typical self - test change o ver temperature 30 0 current consumption (ma) percent of population (%) 25 20 15 10 5 3.7 3.9 4.1 4.3 4.5 2.5 2.7 2.9 3.1 3.3 3.5 08890-012 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 (%) voltage (v) 08890-013 figu re 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 voltage (v) temperature (c) 256 parts 08890-014 figure 14 . v temp output o ver temperature (v ratio = 5 v) 60 50 30 40 10 20 ?20 ?10 0 750 770 810 830 850 790 (g or /s) time (ms) ref y x +45 ?45 08890-015 figure 15 . g and g g sensitivity for a 50 g , 10 ms pulse
ADXRS623 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 1.8 100 1k 10k peak rateout (/s) frequency (hz) latitude longitude rate 08890-016 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 08890-017 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) 08890-018 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) 08890-019 figure 19. typical shift in 90 sec null averages accumulated over 140 hours 0.10 0.05 0 ?0.05 ?0.10 03 6 0 0 1800 1200 3000 2400 600 time (seconds) (/s) 08890-020 figure 20. typical shift in short-term null (bandwidth = 1 hz) 0.1 0.001 0.01 0.0001 10 100k 1k 100 frequency (hz) (/s/ hz rms) 10k 08890-021 figure 21. typical noise spectral density (bandwidth = 40 hz)
ADXRS623 rev. 0 | page 9 of 12 theory of operation the adxrs 623 operates on the principle of a resonator gyro scope . 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 while rotating . 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 that produce the electrical rate signal output. the dual - sensor design rejects external g forces and vibration. fabricating the sensor with 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 application s, 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 the cp5 pin ( 6d, 7d). note that cp5 should not be grounded when power is applied to the adxrs 623. although no d amage 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 623 . setting bandwidth external c apacitor c out is used in combination with the on - chip r out resistor to cr eate a low - pass filter to limit the bandwidth of the adxrs 623 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 manufacturing to be 180 k ? 1%. any external resistor applied be tween the rateout pin (1b, 2a) and the sumj pin (1c, 2c) result s in ( ) ( ) ext ext out r r r + = k180 k180 in general, an additional hardware or software filter is added to attenuate high frequency noise arising from demodulatio n sp ikes at the gyroscope s 14 khz resonant frequency (the noise spikes at 14 khz can be clearly seen in the power spectral density curve shown in figure 21 ). typically, the corner frequency of this additional filter is set to greater than 5 the required bandwidth to preserve good phase response. figure 22 shows the effect of adding a 250 hz filter to the output of an adxrs 623 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 f re quency (hz) (/s/ hz rms) 10k 08890-022 figure 22 . noise spectral density with additional 250 hz filter temperature output a nd calibration it is common practice to temperature - calibrate g yro scope s to improve their overall accuracy. the adxrs 623 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 output 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 08890-023 figure 23 . adxrs 623 temperature sensor structure calibrated p erformance using a three - point calibration technique, it is possible to calibrate the null and sensitivity drift of the adxrs 623 to an overall accuracy of nearly 200/hour. an overall accuracy 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.
ADXRS623 rev. 0 | page 10 of 12 adxrs 623 and supply ratiometr icity the adxrs 623 rateout and temp signals are ratiometric to the v ratio v oltage; that is , the null voltage, rate sensitivity, and temperature outputs are proportional to v ratio . thus, the adxrs 623 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 behavior. typical ratiome t ricity error for null, sensitivity, self - test, and temperature output is o utlined in table 4 . note that v ratio must never be greater than av cc . table 4 . ratiometricity error for various parameters parameter v s = v ratio = 4.8 5 v v s = v ratio = 5. 1 5 v st1 mean 0.3 % 0.09 % sigma 0.21 % 0.19 % st2 mean ?0.15 % ?0.2 % sigma 0.22 % 0.2 % null mean ?0.3 % ?0.0 5% sigma 0.2 % 0.08 % sensitivit y mean 0.0 0 3% ?0.25 % sigma 0.06 % 0.06 % v temp mean ?0.2 % ?0.04 % sigma 0.05 % 0.06 % null adjustment the nom i nal 2.5 v null is for a symmetrical swing range at rateout (1b, 2a). however, a nonsymmetrical output swing may be sui t able in some applicati ons. 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 623 includes a self - test feature that actuates each of the sensing structures and associated electronics as if subjected to angular rate. it 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. 0 v, and st2 causes an opposite change of +1. 0 v. the self - test response follows the viscosity temperature depen d ence of the package atmosphere, approximately 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 t o the st1 and st2 pins. st1 and st2 are deacti - vated 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 623 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 reliability. as an additional failure detection measure, a power - on self - test ca n be performed. ho w ever, som e applications may warrant continu ous self - test while sensing rate. details about continuous self- test techniques are available in the an - 768 application note, using the adxrs150/adxrs300 in continuous self - test mode , avail - able at www.analog.com .
ADXRS623 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 temperature range pa ckage description package o ption adxrs 623 w bbg z C 40c to +105c 32- lead ceramic ball grid array (c bga ) bg -32 -3 adxrs 623 w bbg z- rl C 40c to +105c 32- lead ceramic ball grid array (cbga) bg -32 -3 eval - ADXRS623z evaluation board 1 z = rohs compliant part.
ADXRS623 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. d08890 -0- 3/10(0)

▲Up To Search▲

Price & Availability of ADXRS623

	To Download ADXRS623 Datasheet File
If you can't view the Datasheet, Please click here to try to view without PDF Reader .