QST102 STMicroelectronics, QST102 Datasheet
QST102
Related parts for QST102
QST102 Summary of contents
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... Package February 2008 Capacitive touch sensor device 2 keys with individual key state outputs Description The QST102 is the ideal solution for the design of capacitive touch sensing user interfaces. Touch-sensitive controls are increasingly replacing electromechanical switches in home appliances, consumer and mobile electronics, and in computers and peripherals. Capacitive ...
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... Device operating mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 4.1 Main features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 4.2 Power- 4.3 KOUT output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 4.4 Adjacent key suppression (AKS™ 4.5 Max on-duration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 4.6 Serial validation interface (SVI Design guidelines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 5.1 C sense capacitor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 S 5.2 Sensitivity tuning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 5.2.1 5.2.2 5.2.3 5.3 Power supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 5.4 ESD protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 5.5 Crosstalk precautions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 2/29 Increasing sensitivity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 Decreasing sensitivity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 Key balance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 QST102 ...
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... QST102 5.6 PCB layout and construction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 6 Electrical characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 6.1 Parameter conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 6.1.1 6.1.2 6.1.3 6.1.4 6.1.5 6.2 Absolute maximum ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 6.2.1 6.2.2 6.2.3 6.3 EMC characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 6.3.1 6.3.2 6.3.3 6.4 Operating conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 6.5 Supply current characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 6.6 Capacitive sensing characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 6.7 KOUT pin characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 6.7.1 6.7.2 7 Package mechanical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 7.1 Soldering information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 8 Part numbering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 9 Device revision information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 9.1 Device identification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 9 ...
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... Device overview 1 Device overview The QST102 capacitive touch sensor pure digital solution based on Quantum's patented charge-transfer (QProx™) capacitive technology. This technology allows users to create simple touch panel sensing electrode interfaces for conventional or flexible printed circuit boards (PCB/FPCB). Sensing electrodes are part of the PCB layout (copper pattern or printed conductive ink) and may be used in various shapes (circle, rectangular, etc ...
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... S: supply pin, PP: Output push-pull pin and SNS: Capacitive sensing pin 2. To ensure correct reset of device, a 1nF capacitor must be connected to this pin. During reset phase, this pin must not be driven. 3. During the reset phase, this pin is floating and its state depends on the option resistor. VDD 1 SNSK_SCK2 2 QST102AU6 SNS_SCK2 (1) Type S ...
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... C X can thus be increased to allow larger values and C , and changes in either can result in substantial X S Sense resistor R (10 kΩ) S Sense capacitor C (a few nF) S QST102 , which rise more S reduce the rise tolerated (~5 pF) T Earth C (~20 pF) x ...
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... QST102 3.3 Faulty and unused keys Any sensing channel that does not have its sense capacitor (C either faulty or unused. This channel takes no further part in operation unless a Master- commanded recalibration operation shows it to have an in-range burst count again. Faulty, unused or disabled keys are still bursted but not processed to avoid modifying the sensitivity of active keys ...
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... After recalibration, the key will continue to operate normally, even if partially or fully obstructed. Max On-Duration works independently per channel: a timeout on one channel has no effect on another channel. 8/29 Time = 8 * Burst_Period. The methodology used to measure the CAL Section 6.6: Capacitive sensing characteristics on page QST102 Reference count Reference + EofDeTh Reference + DeTh Key Detection signal 19. ...
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... QST102 3.9 Drift compensation Signal drift can occur because of changes type and quality, the signal may vary substantially with temperature and veiling. If keys S are subject to extremes of temperature or humidity, the signal can also drift crucial that drift be compensated, otherwise false detections, non detections, and sensitivity shifts will follow ...
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... Pins KOUT1 and KOUT2 directly reflect the state of keys ● Selectable locking adjacent key suppression (AKS™) ● Max On-Duration feature ● Serial validation interface (SVI) Figure 5. QST102 schematic diagram V UNREG Keep these parts close to IC Key 1 10kΩ Key 2 10kΩ ...
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... QST102 4.4 Adjacent key suppression (AKS™) The adjacent key suppression (AKS™) function is enabled using the AKS option resistor (pin KOUT1/AKS) as described in Table 3. AKS truth table KOUT1/AKS 4.5 Max on-duration The Max On-Duration time is set to 30 seconds. This means that a continuous “touched” ...
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... S can differ for each channel, permitting differences in sensitivity from key to yields higher sensitivity. Each channel has its own C S capacitors S S for that key will compensate S value and can S capacitors to achieve equilibrium. The R QST102 S S ...
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... QST102 5.3 Power supply If the power supply fluctuates slowly with temperature, the QST device compensates automatically for these changes with only minor changes in sensitivity. However, if the supply voltage drifts or shifts quickly, the drift compensation mechanism is not able to keep up, causing sensitivity anomalies or false detections. ...
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... For additional information on PCB layout and construction, please contact your local ST Sales Office for a list of available application notes. 14/29 loading of one key, cross coupling to another key’s trace can X QST102 ...
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... QST102 6 Electrical characteristics 6.1 Parameter conditions Unless otherwise specified, all voltages are referred to V 6.1.1 Minimum and maximum values Unless otherwise specified the minimum and maximum values are guaranteed in the worst conditions of ambient temperature, supply voltage and frequencies by tests in production on 100% of the devices with an ambient temperature at T the selected temperature range) ...
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... Ratings (1) Ratings (1)( could damage the device if an unintentional internal reset >V while a negative injection is induced Figure 7. Value −65 to +150 150 Maximum value 7.0 −0 +0 maximum is respected maximum IN IN value. A positive INJ(PIN) < QST102 Unit °C Unit V ...
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... QST102 6.2.3 Current characteristics Table 6. Current characteristics Symbol I Total current into V VDD I Total current out of V VSS Output current sunk by KOUT pins I IO Output current source by KOUT pins (2)(3) I Injected current on KOUT pins INJ(PIN) (2) ΣI Total injected current (sum of all I/O and control pins) INJ(PIN) 1 ...
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... Frequency Band 0.1 MHz to 30 MHz =5V, T =+25° MHz to 130 MHz DD A complies with SAE J 130 MHz to 1 GHz 1752/3 SAE EMI Level Ratings Conditions =+25° =+25° QST102 ( MHz Unit DEVICE 20 20 dBμV 13 2.5 - (1) Maximum value Unit 4000 V 500 V ...
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... QST102 Table 10. Electrical sensitivities Symbol LU Static latch-up class DLU Dynamic latch-up class 1. Class description: A Class is an STMicroelectronics internal specification. All its limits are higher than the JEDEC specifications, that means when a device belongs to Class A it exceeds the JEDEC standard. B Class strictly covers all the JEDEC criteria (international standard). ...
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... Between 10% and 90% Min. Default Max. 100 2000 unless otherwise specified. A Min. Typ. Max. ≤ V ± QST102 Unit ms ms Counts Counts Counts Counts Counts Counts s s/level s/level Counts Unit μ ...
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... QST102 6.7.2 Output pin characteristics Subject to general operating conditions for V Table 16. Output pin current (V Symbol Output low level voltage for pin KOUT1 ( Output low level voltage for pin KOUT2 (1) V Output high level voltage for pins KOUTn OH 1. Not tested in production, based on characterization results. ...
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... Iol [mA (KOUT1 pin) -45°C 900 25°C 800 90°C 130°C 700 600 500 400 300 200 100 Iol [mA] QST102 ...
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... QST102 Figure 17. Typical V 100 2.4 2.6 2.8 3 3.2 3.4 3.6 3.8 Figure 18. Typical V 200 180 160 140 120 100 2.4 2.6 2.8 3 3.2 3.4 3.6 3.8 vs. V (KOUT1 pin 500 450 -45°C 400 25°C 90°C 350 130°C 300 250 200 150 100 4 4.2 4.4 4.6 4.8 5 5.2 5.4 5.6 5.8 6 Vdd [V] 900 800 700 600 ...
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... Min. Typ. Max. 0.80 0.90 1.00 0.00 0.02 0.05 0.20 0.25 0.30 0.35 4.35 4.50 4.65 3.50 3.65 3.75 3.35 3.50 3.65 1.96 2.11 2.21 0.80 0.30 0.40 0.50 0.08 Exposed Pad (1) inches Min. Typ. 0.0315 0.0354 0.0000 0.0008 0.0079 0.0098 0.01181 0.1713 0.1771 0.1378 0.1437 0.1319 0.1378 0.0772 0.0831 0.0315 0.01181 0.0157 QST102 EF_ME Max. 0.0394 0.0020 0.0138 0.1831 0.1476 0.1437 0.0870 0.0197 0.0031 ...
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... QST102 7.1 Soldering information In accordance with the RoHS European directive, all STMicroelectronics packages have been converted to lead-free technology, named ECOPACK™. ● ECOPACK™ packages are qualified according to the JEDEC STD-020C compliant soldering profile. ● Detailed information on the STMicroelectronics ECOPACK™ transition program is available on www ...
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... ST Sales Office. The category of second Level Interconnect is marked on the package and on the inner box label, in compliance with JEDEC Standard JESD97. The maximum ratings related to soldering conditions are also marked on the inner box label. 26/29 QST QST102 6 ...
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... QST102 9 Device revision information 9.1 Device identification Figure 20. Device revision identification Table 22. Device revision identification 9.2 Device revision identification The marking on the first line of the package top face identifies the device revision. 9.2.1 Revision 1.0 First device revision. VFQFPN8 Package 102 V10 Marking V10 Device revision information ...
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... Revision history 10 Revision history Table 23. Document revision history Date 20-Feb-2008 28/29 Revision 1 First release. QST102 Changes ...
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... QST102 Information in this document is provided solely in connection with ST products. STMicroelectronics NV and its subsidiaries (“ST”) reserve the right to make changes, corrections, modifications or improvements, to this document, and the products and services described herein at any time, without notice. All ST products are sold pursuant to ST’s terms and conditions of sale. ...