QST108KT6 STMicroelectronics, QST108KT6 Datasheet
QST108KT6
Specifications of QST108KT6
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QST108KT6 Summary of contents
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... QTouch™ and QProx™ are trademarks of the Quantum Research Group. Individual key state outputs or I Rev 5 QST108 Not For New Design LQFP32 (7x7 mm) Order codes QST108KT6 2 Interface -40° to +85° C LQFP32 (7x7 mm) 1/51 www.st.com 1 ...
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Contents Contents 1 Device overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...
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QST108 5 Design guidelines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...
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Contents 9.1 Device revision identification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47 ...
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QST108 1 Device overview The QST108 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 ...
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... GPO5/OPT5/KOUT5 PP (HS) PP/OD (2) 3 OPT6/KOUT6/IRQ (3) 4 KOUT7/I2C_SDA (3) 5 KOUT8/I2C_SCL 6/ (HS) 4 QST108KT6 1) (HS) 5 RESET DD_1 (1) Stand-alone mode function Key 4 output / BCD output 4 and MOD_0 option resistor Key 5 output and MOD_1 option resistor Key 6 output and (HS) OM_0 option resistor TOD Key 7 output ...
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QST108 Table 2. Device pin description (continued) Pin Pin name Type 6 RESET DD_1 9 V SS_1 10 V SS_2 11 V SS_3 12 V SS_4 13 V DD_2 14 SNS_SCK1 15 SNSK_SCK1 16 SNS_SCK2 17 ...
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QST touch sensing technology 3 QST touch sensing technology 3.1 Functional description QST devices employ bursts of charge-transfer cycles to acquire signals. Burst mode permits low power operation, dramatically reduces RF emissions, lowers susceptibility to RF fields, and yet permits ...
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QST108 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 ...
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QST touch sensing technology Figure 3 shows an example of detection with DI=2 and EDI=2 meaning 3 consecutive samples are necessary to trigger the key detection or end of detection Figure 3. Detection signals Hysteresis = Sampling point 3.6 Self-calibration ...
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QST108 3.9 Max On-Duration The device can time out and automatically recalibrate each key independently after a fixed duration of continuous touch detection. This prevents the keys from becoming ‘stuck on’ due to foreign objects or other sudden influences. This ...
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QST touch sensing technology Figure 4 illustrates an example of the drift compensation algorithm following a temperature change. Figure 4. Drift compensation example 3.11 Adjacent key suppression (AKS™) Adjacent key suppression (AKS™ Quantum-patented feature which prevents multiple keys ...
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QST108 4 Device operating modes 4.1 Reset and power-up At power-up, the device configures itself according to the pull-up or pull-down option resistors present on pins OPT1 to OPT6. The device start-up and configuration may take ...
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Device operating modes ● Free run in detect The behavior in this mode is the same as in the standard low power mode except that the sleep window insertion is always skipped if any of the active keys is detected ...
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QST108 4.5 Stand-alone mode This mode allows the user to simply replace existing mechanical switch interface with a capacitive sensing solution designed for maximum flexibility and can accommodate most popular sensing requirements via option resistors (see 4.5.1 Main ...
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Device operating modes Figure 5. Stand-alone mode typical schematic 2.4~5.5V V UNREG Volt. Reg. 4.7µF Keep these parts close Key8 10kΩ Key7 10kΩ Key6 10kΩ ...
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QST108 4.5.3 Option descriptions Adjacent key suppression (AKS™) The QST108 features an adjacent key suppression (AKS™) function. This function is enabled using the AKS option resistor (OPT2) in standard output mode as described in Table of the option resistor configuration. ...
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Device operating modes Output mode option The QST108 offers several outputs mode to fit any existing application. Table 7. Output mode (OM) truth table OPT6/OM V Individual key state output mode: One output per sensing channel SS V BCD output ...
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QST108 2 4 mode 2 The I C mode offers the largest configurability and functionality of the QST108. 4.6.1 Main features ● 5 general-purpose outputs ● Configuration AKS groups ● Additional low power modes ...
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Device operating modes 4.6.2 General-purpose outputs mode allows to drive general-purpose outputs. These output pins are configured in output push pull mode 0 by default. Their state can be changed using the SET_GPIO_STATE I ...
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QST108 2 4.6 address selection The QST108 slave address is programmable using the option resistors mapped on pins OPT2 to OPT4 (see Table 9. I²C address versus option resistor Option configuration OPT4 OPT3 ...
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Device operating modes Table 10. Supported commands (continued commands GET_DEVICE_INFO Write 0x85 0x15 MainVers SubVers NbSCkey NbMCkey Read ‘Q’ ’S’ ‘T’ ‘1’ ‘0’ ‘8’ Checksum GET_KEY_ERROR Write 0xC4 0x10 KeyError1 Read KeyError2 ... KeyError8 CheckSum GET_KEY_STATE Write ...
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QST108 Table 10. Supported commands (continued commands SET_KEY_ACTIVATION (see Note 4) 0x97 KeyActivation Write Checksum Read ErrCode SET_KEY_GROUP 0x00 0x09 AKSGrpMode Key1Grp Write Key2Grp ...Key8Grp CheckSum Read ErrCode SET_LOW_POWER_MODE 0x92 LowPowerMode Write Checksum Read ErrCode SET_MAX_ON_DURATION 0x8A ...
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Device operating modes Error codes Table 11 lists the I Table 11. ErrCode ErrCode 0x01 No Error 0x83 Command not supported 0x85 Parameter not supported 0xA1 Parity Error 0xA3 Checksum Error 0xE0 Initialization process (GET_FIRMWARE_INFO command not received) KeyError byte ...
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QST108 Key activation description Table 14. KeyActivation Bit 7 Bit 6 Key 0 Activation Key activation (Bit 7) 0: Key disabled 1: Key enabled Key identifier (Bits 3:0) 0000: All keys 0001: Key 1 0010: Key 2 0011: Key 3 ...
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Device operating modes GPO state description Table 16. GPOState Bit 7 Bit GPOState Defines the state of the selected general-purpose output pin. For more information, see Section 4.6.2: General-purpose outputs on page 0: GPO state is ‘0’ ...
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QST108 5 Design guidelines 5.1 C sense capacitor S The C sense capacitors accumulate the charge from the key electrodes and determine S sensitivity. Higher values of C The values of C can differ for each channel, permitting differences in ...
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Design guidelines 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 ...
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QST108 It is important to limit the amount of stray capacitance on the SNS terminals, for example by minimizing trace lengths and widths to allow for higher gain without requiring higher values Under heavy delta-C S cause ...
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Electrical characteristics 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 ...
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QST108 6.2 Absolute maximum ratings Stresses above those listed as “absolute maximum ratings” may cause permanent damage to the device. This is a stress rating only and functional operation of the device under these conditions is not implied. Exposure to ...
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Electrical characteristics 6.3 EMC characteristics Susceptibility tests are performed on a sample basis during product characterization. 6.3.1 Functional EMS (electro magnetic susceptibility) The product is stressed by two electro magnetic events until a failure occurs: ● ESD: Electro-Static Discharge (positive ...
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... 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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Electrical characteristics 6.4 Operating conditions Table 27. Operating conditions Symbol V Operating supply voltage DD T Operating temperature A 6.5 Supply current characteristics Table 28. Supply current characteristics Symbol Parameter Average suppy current I (FR) DD Free Run mode I ...
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QST108 6.6 Capacitive sensing characteristics Table 29. External sensing components Symbol C Sense capacitor S C Equivalent electrode capacitor X C Equivalent touch capacitor T R Serial resistor S Table 30. Capacitive sensing parameters Symbol t Calibration duration CAL t ...
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Electrical characteristics 6.7 KOUTn/OPTn/GPOn pin characteristics 6.7.1 General characteristics Subject to general operating conditions for V Table 31. General characteristics Symbol V Input low level voltage IL V Input high level voltage IH V Schmitt trigger voltage hysteresis Hys I ...
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QST108 Figure 11. Typical 2 pins OL load DD 1200 -40°C 25°C 1000 85°C 125°C 800 600 400 200 [mA] ...
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Electrical characteristics Figure 19. Typical Pins DD OH load DD 1800 -40°C 1600 25°C 1400 85°C 125°C 1200 1000 800 600 400 200 0 ...
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QST108 6.8 RESET pin T = -40°C to 125°C, unless otherwise specified. A Table 33. RESET pin characteristics Symbol Parameter V Input low level voltage IL V Input high level voltage IH Schmitt trigger voltage V hys hysteresis Output low ...
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Electrical characteristics control interface 6.9 Subject to general operating conditions for V 2 The QST108 I C interface meets the requirements of the Standard I protocol described in the following table with the restriction mentioned below: Refer ...
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QST108 Figure 22. Typical application with I 4.7kΩ BUS START SDA t t f(SDA) SCL t t h(STA) w(SCKH bus and timing diagram 4.7kΩ 100Ω SDA 100Ω SCL QST device r(SDA) ...
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Package mechanical data 7 Package mechanical data Figure 23. 32-pin low profile quad flat package (7x7) outline Seating plane Pin 1 identification 42/ ccc ...
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QST108 Table 36. 32-pin low profile quad flat package mechanical data Dim 0.050 A2 1.350 b 0.300 c 0.090 D 8.800 D1 6.800 D3 E 8.800 E1 6.800 0.450 L1 K ccc 1. Values in ...
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Package mechanical data Figure 24. 32-pin LQFP32 (7x7 mm) recommended footprint 6.10 9.70 All dimensions are in millimeters. 44/51 0. 0.30 7.30 7. 6.10 9.70 QST108 1.20 17 0.50 24 1.20 Ai15211 ...
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... QST108 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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Part numbering 8 Part numbering Table 38. Ordering information scheme Example: Device type QST = Capacitive touch sensor Device sub-family 1: QTouch ( QMatrix ( QSlide/QWheel ( 11: QTouch ...
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QST108 9 Device revision information 9.1 Device revision identification The marking on the right side of the second line (Line B) of the package top face identifies the device revision. Figure 25. Device revision identification (TQFP package) Table 39. Device ...
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Device revision information 9.2.2 Revision 2.3 ● When the device enters Low Power mode, an additional sleep time is inserted after each burst, instead of once after every complete burst cycle result, if only one burst is required, ...
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QST108 10 Revision history Table 40. Document revision history Date 8-Jun-2007 15-Jun-2007 26-Sep-2007 22-Nov-2007 Revision 1 Initial release. 2 Datasheet status changed to Preliminary Data. Removed Beeper function. Changed LED output pins to GPO pins. Updated pin names and functions ...
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Revision history Table 40. Document revision history (continued) Date 11-Jul-2008 50/51 Revision Changed datasheet status to Not for new design. Updated Figure 2: QTouch™ measuring circuitry resistor.* Updated Section 3.5: Detection integrator filter on page 9 Figure 3: Detection signals ...
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... QST108 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. ...