at42qt113b ATMEL Corporation, at42qt113b Datasheet
at42qt113b
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at42qt113b Summary of contents
Page 1
... Self-calibration, auto drift compensation, noise filtering • Applications: – Light switches – Proximity sensors – Appliance control – Security systems – Access systems – Pointing devices – Elevator buttons – Consumer devices ™ QProx Charge-transfer Touch Sensor AT42QT113B 9525B–AT42–09/10 ...
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... OUT O 3 OPT1 I 4 OPT2 I 5 GAIN I 6 SNS1 I/O 7 SNS2 I/O 8 Vss AT42QT113B 2 Vdd 1 8 OUT 2 7 OPT1 3 6 OPT2 4 5 Comments Power Output state inverse – 0 when touched Option pin 1 Option pin 2 Gain setting Sense pin Sense pin Supply ground ...
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... Figure 1-1 on page 3 • Section 4.1 on page • Section 5.2 on page 2. Overview of the AT42QT113B 2.1 Introduction The QT113B charge-transfer (QT detecting near-proximity or touch. It will project a proximity sense field through air, and any dielectric like glass, plastic, stone, ceramic, and most kinds of wood. It can also turn small metal-bearing objects into intrinsic sensors, making them responsive to proximity or touch ...
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... The IC is responsive to both Cx and Cs, and changes in Cs can result in substantial changes in sensor gain. Option pins allow the selection or alteration of several special features and sensitivity. Figure 2-1. Result Start AT42QT113B 4 4). A 14-bit single-slope switched capacitor analog-to-digital converter Appendix A on page Internal Switching and Timing Done ...
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... Even when battery powered, just the physical size of the PCB and the object into which the electronics is embedded will generally be enough to couple a few picofarads back to local earth. 9525B–AT42–09/10 2-2) having lower Cx than a solid plane. Sensitivity may even remain the same, as the AT42QT113B Figure 2- ...
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... To stop field spreading only necessary to surround the touch electrode on all sides with a ring of metal connected to circuit ground; the ring can be on the same or opposite side from the electrode. The ring will kill field spreading from that point outwards. AT42QT113B 6 Kirchoff’s Current Law C ...
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... Keep ground away from the electrodes and traces. 9525B–AT42–09/10 Shielding Against Fringe Fields Sense Sense wire wire U nshielded Shielded Electrode E lectrode AT42QT113B Table 3-1 on page Appendix A on page 20). The value of Cs 9). 7 ...
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... With large values of Cs and small values of Cx, drift compensation will appear to operate more slowly than with the converse. Note that the positive and negative drift compensation rates are different. AT42QT113B 8 Figure 3-1 on page Drift Compensation ...
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... CMOS buffering. 74HC or 74AC series gates can directly power the QT113B, as can most other microcontrollers. 9525B–AT42–09/10 Gain Setting Strap Options Gain Tie Pin 5 To... Vdd Vss (Gnd) Table 3-2 on page Figure 3-2) will serve as both power and forced recalibration. The AT42QT113B Table 3-1. These 10). 9 ...
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... On-Duration expires (if not infinite), whichever occurs first max on-duration timeout occurs first, the sensor performs a full recalibration and the output becomes inactive until the next detection. In this mode, three Max On-Duration timeouts are available: 10 seconds, 60 seconds, and infinite. AT42QT113B 10 Powering From a CMOS Port Pin PORT X.m CMOS microcontroller PORT X ...
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... Getting HeartBeat Pulses With a Pull-down Resistor Vdd HeartBeat™ Pulses Vdd OUT SNS2 OPT1 GAIN 4 6 OPT2 SNS1 Vss 8 Using a Micro to Obtain HeartBeat Pulses In Either Output State 2 PORT_M Microcontroller 4 PORT_M.y AT42QT113B Figure 3-3 on Figure 3-4, the microcontroller can 7 OUT SNS2 5 OPT1 GAIN 6 OPT2 SNS1 11 ...
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... Charge sampler Cs can be virtually any plastic film or medium-K ceramic capacitor. The acceptable Cs range is from 500 nF depending on the sensitivity required; larger values of Cs demand higher stability to ensure reliable sensing. Acceptable capacitor types include PPS film, polypropylene film, NPO/C0G ceramic, and X7R ceramic. AT42QT113B 12 Eliminating HB Pulses G ATE OR ...
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... Vdd and Vss; the bypass capacitor should be placed very close to the device’s power pins. 9525B–AT42–09/10 and Table 3-2 on page 10 show the option strap configurations available. for the power supply range volts current drain averages less Section 3.2.5 on page 12). 3) should be placed as close to the body of the chip as possible so that AT42QT113B 13 ...
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... However, Rseries and Cs must both be placed very close to the body of the IC so that the lead lengths between them and the IC do not form an unfiltered antenna at very high frequencies. AT42QT113B 14 14. The Cs capacitor and Rseries (see ...
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... Minimum Typical Maximum 1,000 2,500 100 0.2Vdd 0.9Vdd 0.6 Vdd-0.7 ± 1,000 10 AT42QT113B o C Units Notes µA V/s Required for proper startup V OPT1, OPT2 V OPT1, OPT2 V OUT, 4mA sink V OUT, 1mA source µA OPT1, OPT2 ...
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... Response time R T Heartbeat pulse width HB F Burst frequency Q 5.4.1 Signal Processing Description Threshold differential Hysteresis Consensus filter length Positive drift compensation rate Negative drift compensation rate Post-detection recalibration timer duration AT42QT113B 16 Minimum Typical Maximum 330 1.95 2.9 4.9 3.1 30 310 172 Min Typ Max ...
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... E. Cheyenne Mtn. Blvd. Colorado Springs, CO 80906 R 9525B–AT42–09/ Top View TITLE 8S1, 8-lead (0.150" Wide Body), Plastic Gull Wing Small Outline (JEDEC SOIC) AT42QT113B ∅ End View COMMON DIMENSIONS (Unit of Measure = mm) MIN MAX SYMBOL NOM A 1.35 – ...
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... Marking Either part marking is used. AT42QT113B 18 Abbreviation of 113B Part number: 113B AT42QT 1R0 Code Revision 1.0, Released Pin 1 ID Date Code W=Week code W week code number 1-52 where: A=1 B=2 .... Z=26 then using the underscore A=27...Z=52 Abbreviation of QT113B Part number: QT113B AT42 1R0 Code Revision 1.0, Released YYWW ...
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... Part Number Part Number AT42QT113B-ISG 5.8 Moisture Sensitivity Level (MSL) 9525B–AT42–09/10 Description 8-pin SOIC RoHS compliant MSL Rating Peak Body Temperature MSL3 AT42QT113B Specifications o 260 C IPC/JEDEC J-STD-020 19 ...
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... Appendix A. Figure A-1. Figure A-2. Figure A-3. AT42QT113B 20 Typical threshold Sensitivity vs Cx, High Gain, At Selected Values of Cs; Vdd = 3.0V Figure 4-1 - Typical ThresholdS ensitivityvs. Cx, HighGain electedValuesof Cs; Vdd 0.001 0pF 10pF 20pF CxLoad Load, pF Typical threshold Sensitivity vs Cx, Low Gain, At Selected Values of Cs ...
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... Revision History Revision Number Revision A – February 2009 Revision B – September 2010 9525B–AT42–09/10 History Initial release for chip revision 1.0. Address information on back page updated. Regulator information removed. AT42QT113B 21 ...
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... Atmel Corporation. All rights reserved. Atmel ™ ™ HeartBeat , QProx and others are trademarks of Atmel Corporation or its subsidiaries. Other terms and product names may be registered trademarks or trademarks of others. International Atmel Asia Atmel Munich GmbH Unit 01-05 & 16, 19F ...