QT140-DG Atmel, QT140-DG Datasheet
QT140-DG
Specifications of QT140-DG
Related parts for QT140-DG
QT140-DG Summary of contents
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... PC Peripherals Backlighted buttons QT140 / QT150 charge-transfer (“QT’”) QTouch ICs are self-contained digital controllers capable of detecting near-proximity or touch electrodes. They allow electrodes to project independent sense fields through any dielectric like glass, plastic, stone, ceramic, and wood. They can also turn metal-bearing objects into intrinsic sensors, making them responsive to proximity or touch ...
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... Channel 1 output, o-d or p-p Channel 2 output, o-d or p-p Channel 3 output, o-d or p-p Channel 4 output, o-d or p-p Channel 5 output, o-d or p-p (n/c on QT140) Synchronization pin (I/O pin - pull high with 10K) Option Mode (Input pin - see Table 2-1) Option Mode (Input pin - see Table 2-1) ...
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... The sensor’s PCB however may be physically small, so there may be little ‘free space’ coupling (Cx1 in Figure 1-2) between it and the environment to Figure 1-3 Mesh Electrode Geometry IZE AND OCATION K EYS G ROUNDS QT140/150 1.01/1102 ...
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... Decreasing Sensitivity In some cases the circuit may be too sensitive. Gain can be lowered further by a number of strategies: a) making the electrode smaller, b) making the electrode into a sparse mesh using a high space-to-conductor ratio (Figure 1-3 decreasing the Cs capacitors nse w ire QT140/150 1.01/1102 ...
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... Figure 1-6 Basic Circuit (QT140, SSOP Package) Figure 1-8 Synchronized QT140, QT150 Circuits Figure 1-7 Basic Circuit (QT150, SSOP Package) ...
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... QT140/QT150 SPECIFICS 2.1 SIGNAL PROCESSING These devices process all signals using 16 bit math, using a number of algorithms pioneered by Quantum. These algorithms are specifically designed to provide for high survivability in the face of adverse environmental changes. 2.1 RIFT OMPENSATION Signal drift can occur because of changes in Cx, Cs, and Vdd over time ...
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... Table 2-1 OPT Strap Options OPT1 OPT2 Max On-Duration Gnd Vdd Vdd Gnd Vdd Vdd Gnd Gnd AKS=0: Disabled; AKS=1: Enabled QT140/150 1.01/1102 10s 60s 10s infinite ...
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... All the chips in a system, whether 1 or 20, should connect to this common line with a single 10K pullup resistor. A single QT140 or QT150 must also use a pullup resistor. SYNC floats high during the Channel 1 sensing burst. When the IC completes Channel 1 sensing, it pulls down SYNC. ...
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... Ferrites over the power wiring may be required to attenuate line injected noise. Achieving RF immunity requires diligence and a good working knowledge of grounding, shielding, and layout techniques. Very few projects involving these devices will fail EMC tests once properly constructed. 9 QT140/150 1.01/1102 ...
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... DD Operating temperature range, 4.5V - 5.5V (QT140-AS, QT150-AS -40 - +105C Operating temperature range, 3.0V - 4.5V (QT140-AS, QT150-AS -40 - +85C Operating temperature range, all voltages (QT140-D, QT150-D) ...
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... Cs, nF Figure 4-3 11 Notes From signal reference From threshold Option pin selected Burst Duration v s. Cs, Cx 4000 3500 3000 2500 2000 1500 1000 500 Figure 4 5pF Cx = 10pF Cx = 15pF Cx = 22pF Cx = 33pF Cx = 47pF 200 250 QT140/150 1.01/1102 Cs = 47nF Cs = 39nF Cs = 22nF Cs = 10nF 50 ...
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... W e ø E Base level Inches Min Max 0.396 0.407 0.301 0.311 0.205 0.212 0.026 0.026 0.010 0.015 0.022 0.037 0.005 0.009 0º 8º 0.068 0.078 0.002 0.008 QT140/150 1.01/1102 Notes BSC 4 places Typical BSC Typical Notes ...
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... ORDERING INFORMATION PART QT140-D QT140-AS QT150-D QT150-AS lQ TEMP RANGE PACKAGE 0 - 70C PDIP-28 -40 - 105C SSOP- 70C PDIP-28 -40 - 105C SSOP-28 13 MARKING QT140 QT140-A QT150 QT150-A QT140/150 1.01/1102 ...
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The specifications set out in this document are subject to change without notice. All products sold and services supplied by QRG are subject to our Terms and Conditions of sale and supply of services which are available online at ...