ATS643lsh ? conceptual conceptual datasheet (subject to change without notice) true zero - speed, two - wire, miniature gear tooth sensor pin 1: supply/current output pin 2: nc pin 3: test pin pin 4: ground the ATS643lsh is an optimized hall - effect sensi ng integrated circuit and magnet combination that provides a user - friendly solution for true zero - speed digital gear - tooth sensing in two - wire applications. the sensor consists of a single - shot molded plastic package that includes a samarium cobalt magnet , a pole piece, and a hall effect ic that has been optimized to the magnetic circuit. this small package can be easily assembled and used in conjunction with a wide variety of gear shapes and sizes. the integrated circuit incorporates a dual element hall - effect sensor and signal processing circuitry that switches in response to differential magnetic signals created by ferrous targets. the device contains a sophisticated compensating circuit to eliminate magnet and system offsets. digital tracking of the analog signal is used to achieve true zero speed operation. a - d and d - a converters are used to adjust the device gain and offset at power up resulting in air gap independent switch - points, which greatly improves output accuracy. the regulated current ou tput is configured for two - wire operation. this sensor is ideal for obtaining speed and duty cycle information in gear - tooth - based applications such as transmission speed sensing. absolute maximum ratings supply voltage, v cc 26.5 v* reverse supply voltage, v r ? 18 v operating temperature range, t a ? 40 c to 150 c* storage temperature, t s 170 c package power rating, j ja 126 c/w maximum junction temperature, t j, continuous . . . . . . . . . . . . . . . . . . . . . 165 c * operation at increased supply voltages and temperatures is described in the applications information . benef its / features s fully optimized differential digital gear tooth sensor s single chip sensing ic for high reliability s internal current regulator for 2 - wire operation s vibration immunity s small mechanical size (8 mm dia x 5.5 mm length) s air gap independent switch - points s digital output representing gear profile s precise duty cycle over temperature s large operating air gaps s <2 ms power up time s agc and reference adjust circuit s true zero - speed operation s under - voltage lockout s wide operating voltage range s defined power - on state
ATS643lsh true zero - speed gear tooth sensor ? allegro confidential rev 2.1, mhn, 09.may.2003 page 2 of 9 115 northeast cutoff, box 1 5036 worcester, massachusetts 01615 - 0036 (508) 853 - 5000 copyright ? 1993, 1995 allegro microsystems, inc. operating characteristics: valid over operating temperature range unless otherwise noted. limits characteristics symbol test conditions min. typ. max. units electrical characteristics supply voltage v cc operating, t j < 165 c 4.0 24 v und er voltage lockout v cc(uv) v cc 0 ? 5 v - 3.5 vccATS643lsh ? i1 i cc high current state: icc high 12.0 14.0 16.0 ma low current state: icc low 5.9 7 8.4 ma supply current ATS643lsh ? i2 i cc high current state: icc high 11.8 14.0 16.8 ma supply current ratio icc high / icc low ratio o f high current to low current tbd - - power - on state characteristics power - on state s po v cc 0 ? 5 v - icc high - - power - on time 1 t on gear speed < 100 rpm - 1 2 ms output stage output slew rate t s r s = 100 w , c s = 10 pf - 7 - ma/ m s 1 power up time is the time requi red to complete the internal automatic offset adjust; the dac?s are then ready for peak acquisition.
ATS643lsh true zero - speed gear tooth sensor ? allegro confidential rev 2.1, mhn, 09.may.2003 page 3 of 9 115 northeast cutoff, box 1 5036 worcester, massachusetts 01615 - 0036 (508) 853 - 5000 copyright ? 1993, 1995 allegro microsystems, inc. operating cha racteristics: valid with reference target unless otherwise specified limits characteristics symbol test conditions min. typ. max. units switch point characteristics rotation speed s max reference target 0 12,000 rpm bandwidth f - 3db 25 40 - khz op erate point bop% % of peak to peak referenced from pdac to ndac, ag < agmax; +65 % release point brp% % of peak to peak referenced from pdac to ndac, ag < agmax; +35 % calibration initial calibration c i rising output edges for accurate edge det ection 3 edges agc disable c f rising output edges 3 edges dac characteristics dynamic offset cancellation 2 60 - g pdac / ndac number of bits for tracking both positive and negative signal peaks 9 bit 2 the device will compensate magnetic and installation offsets up to 80 gauss. offsets greater than 80 gauss may cause inaccuracies in the output.
ATS643lsh true zero - speed gear tooth sensor ? allegro confidential rev 2.1, mhn, 09.may.2003 page 4 of 9 115 northeast cutoff, box 1 5036 worcester, massachusetts 01615 - 0036 (508) 853 - 5000 copyright ? 1993, 1995 allegro microsystems, inc. limits characteristics symbol test cond itions min. typ. max. units operating characteristics: using reference target and valid over operating temperature range operational air gap range 3 op ag duty cycle within specification 0.5 2.5 mm maximum operational air gap range op maxag ou tput switching: duty cycle not within specifications tbd - - mm duty cycle variation dc wobble < 0.5mm valid over operating air gap range 10 %dc operating signal range sig duty cycle within specification tbd - 1400 g minimum operating signal sig min o utput switching: duty cycle not in specification tbd - - g + b (gauss) 100% brp% bop% brp% bop% ATS643 switchpoints valley tooth - b (gauss) 0 3 ope rating air gap is dependent on the available magnetic field. the available field is target geometry and materiel dependent and should be independently characterized. the field available from the reference target is given in the reference gear parameter se ction of the datasheet.
ATS643lsh true zero - speed gear tooth sensor ? allegro confidential rev 2.1, mhn, 09.may.2003 page 5 of 9 115 northeast cutoff, box 1 5036 worcester, massachusetts 01615 - 0036 (508) 853 - 5000 copyright ? 1993, 1995 allegro microsystems, inc. reference gear parameters limits characteristics symbol test conditions min. typ. max. units reference gear dimensions (60 - 0) diameter g d - 120 - mm thi ckness g t - 6 - mm tooth width t w - 3 - mm valley width v w - 3 - mm valley depth v d - 3 - mm material low carbon steel reference gear magnetic profile vs. position over air gap 2 tooth - valley transitions -700 -600 -500 -400 -300 -200 -100 0 100 200 300 400 500 600 700 0 1 2 3 4 5 6 7 8 9 10 11 12 position [] differential flux density [gauss] 0.50mm 0.75mm 1.00mm 1.25mm 1.50mm 1.75mm 2.00mm reference gear peak to peak field vs. air gap 0 200 400 600 800 1000 1200 1400 1600 1800 0 0.5 1 1.5 2 2.5 3 3.5 4 air gap (mm) p-p (g)
ATS643lsh true zero - speed gear tooth sensor ? allegro confidential rev 2.1, mhn, 09.may.2003 page 6 of 9 115 northeast cutoff, box 1 5036 worcester, massachusetts 01615 - 0036 (508) 853 - 5000 copyright ? 1993, 1995 allegro microsystems, inc. mechanical information component material function value sensor package material thermoset epoxy ma x. temperature 170c 1 leads copper, 0.016? dia, 0.050? spacing lead coating solder, tin / lead 90/10 2 1 temperature excursions of up to 225c for 2 minutes or less are permitted. 2 industry accepted soldering techniques are acceptable for this sub - assembly as long as the indicated maximum temperatures for each component are not exceeded. please see the allegro ( http://www.allegromicro.com/ ) website for soldering profile. device qualification program test name test conditions test length # of lots sample / lot comments pre/post test ta = room, hot, cold high temperature operating life (htol) ta = 150c, tj = 170c 408 hrs 1 77 jesd22 - a108 high temperature bake (htb) ta = 170c 1000 hrs 1 77 jesd22 - a103 pre conditioning (pc) 85c/85%rh 168 hrs 1 231 jesd22 - a112 & a113 temperature humidity bias (thb) or hast 85c/85%rh 130c/85%rh 1000 hrs 50 hrs 1 77 jesd2 2 - a101 jesd22 - a110 autoclave (ac) 121c/15 psig 96 hrs 1 77 jesd22 - a102 temperature cycle (tc) - 65c to +150c or - 50c to +150c 500 cycles 1000 cycles 1 77 jesd22 - a104 external visual (ev) physical dimensions (pd) 1 30 lead integrity 1 45 bond pull strength 1 30 esd hbm & mm 1 3 per model per v step jesd22 - a114 & a115,cdf - aec - q100 - 002, 003 & 011 solderability (sd) 1 15 jesd22 - b102 early life failure rate (elfr) 125c or 150c 48 hrs 24 hrs 1 800 jesd22 - a108 gate leakage (gl ) 1 6 cdf - aec - q100 - 006 electrical distributions (ed) ta = room, hot, cold 3 30
ATS643lsh true zero - speed gear tooth sensor ? allegro confidential rev 2.1, mhn, 09.may.2003 page 7 of 9 115 northeast cutoff, box 1 5036 worcester, massachusetts 01615 - 0036 (508) 853 - 5000 copyright ? 1993, 1995 allegro microsystems, inc. functional block dia gram typical applications configuration ATS643 2 wire ion/ioff battery + - 0.01uf 100 ohm sensor assembly out hall amp agc thresh logic threshp threshn pdac internal regurator vcc ndac v neg reference generator & updates offset adjust
ATS643lsh true zero - speed gear tooth sensor ? allegro confidential rev 2.1, mhn, 09.may.2003 page 8 of 9 115 northeast cutoff, box 1 5036 worcester, massachusetts 01615 - 0036 (508) 853 - 5000 copyright ? 1993, 1995 allegro microsystems, inc. sensor package lsh package reference dimensions only
ATS643lsh true zero-speed gear tooth sensor ? allegro confidential rev 2.1, mhn, 09.may.2003 page 9 of 9 115 northeast cutoff, box 1 5036 worcester, massachusetts 01615 - 0036 (508) 853 - 5000 copyright ? 1993, 1995 allegro microsystems, inc. allegro microsystems, inc. reserves the right to make, from time to time, such departures from the detail specifications as may be required to permit improvements in the design of its products. the information included h erein is believed to be accurate and reliable. however, allegro microsystems, inc. assumes no responsibility for its use; nor for any infringements of patents or other rights of third parties which may result from its use.
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