QST104KT6 STMicroelectronics, QST104KT6 Datasheet
QST104KT6
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QST104KT6 Summary of contents
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... QTouch™ and QProx™ are trademarks of the Quantum Research Group. Table 1. Feature Operating supply voltage 2.4 to 5.5 V Supported interfaces Operating temperature Package Rev 2 QST104 LQFP32 (7x7 mm) Device summary Order code QST104KT6 Individual key state outputs Interface -40° to +85° C LQFP32 (7x7 mm) www.st.com 1/45 1 ...
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Contents Contents 1 Device overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...
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QST104 5 Design guidelines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...
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Device overview 1 Device overview The QST104 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 ...
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... OPT6/IRQ (3) 4 I2C_SDA (3) 5 I2C_SCL GPO5/OPT5 (HS) IRQ/OPT6 (HS I2C_SDA (HS) 4 QST104KT6 1) I2C_SCL (HS) 5 RESET DD_1 (1) Stand-alone mode function Key 4 output / BCD output 4 and MOD_0 option resistor PP/OD OM_0 option resistor ...
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Pin description 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 ...
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QST104 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 excellent speed. Signals ...
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QST touch sensing technology 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 ...
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QST104 3.7 Fast positive recalibration The device autorecalibrates a key when its signal reflects a decrease in capacitance higher than a fixed threshold (PosRecalTh) for a defined number of acquisitions (PoseRecalI). 3.8 Forced key recalibration A recalibration of the device ...
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QST touch sensing technology Caution: When only one key is enabled or if keys are very close together, the common drift compensation must be disabled or its rate must be reduced to ensure correct device operation. 3.11 Adjacent key suppression ...
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QST104 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 ● Deep Sleep mode In Deep Sleep mode, the device enters a very low power mode indefinitely. The device resumes its operations after receiving Caution frame is received while in ...
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QST104 Figure 3. Stand-alone mode typical schematic 2.4~5.5V V UNREG Volt. Reg. 4.7µF Keep these parts close Key4 10kΩ Key3 10kΩ Key2 10kΩ Key1 10kΩ 4.5.2 KOUT outputs KOUTn outputs ...
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Device operating modes 4.5.3 Option descriptions Adjacent key suppression (AKS™) The QST104 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 ...
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QST104 Output mode option The QST104 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 mode: Binary-coded ...
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Device operating modes 2 4 mode 2 The I C mode offers the largest configurability and functionality of the QST104. 4.6.1 Main features ● 13 general-purpose outputs ● Configuration AKS groups ● Additional low ...
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QST104 2 Figure mode typical schematic V UNREG 4.7µF Keep these parts close Key4 10kΩ Key3 10kΩ Key2 10kΩ Key1 10kΩ 4.6.2 General-purpose outputs ...
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Device operating modes Figure 5. Optional LED schematic 4.6.3 IRQ pin The IRQ pin is an open drain output with an internal pull-up. It can be used to inform the Master device about any change in the key status. The ...
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QST104 2 4.6 address selection The QST104 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’ ‘4’ Checksum GET_KEY_ERROR Write 0xC4 0x11 KeyError1 Read KeyError2 ... KeyError4 CheckSum GET_KEY_STATE Write ...
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QST104 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 0x83 0x85 0xA1 0xA3 0xE0 KeyError byte description Table 12. KeyError byte description Bit 7 Bit 6 Key State 0 Key state (Bit 7) When ...
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QST104 Key activation description Table 14. KeyActivation Bit 7 Bit 6 Key 0 Activation Key activation (Bit 7) 0: Key enabled 1: Key disabled Key identifier (Bits 3:0) 0000: All keys 0001: Key 1 0010: Key 2 Low power mode ...
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Device operating modes GPO state description Table 16. GPOState Byte Bit 7 GPO 8 GPOState1 state GPOState2 0 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 ...
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QST104 Key debug state description Table 19. KeyDbgState Value 0x01 0x02 0x04 0x08 0x11 0x14 0x24 Description On-going calibration Key released Key touched Key in error Key calibration filter triggered (PosRecalI) Key detection filter triggered (DI) Key end of detection ...
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Design guidelines 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 key or to balance unequal sensitivities. ...
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QST104 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 ...
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Design guidelines 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 ...
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QST104 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 ...
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Electrical characteristics 6.1.5 Pin input voltage The input voltage measurement on a pin of the device is described in Figure 7. Pin input voltage 6.2 Absolute maximum ratings Stresses above those listed as “absolute maximum ratings” may cause permanent damage ...
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QST104 Table 22. Current characteristics Symbol I Total current into V VDD I Total current out of V VSS Output current sunk by RESET pin I Output current sunk by output pin IO Output current source by output pin Injected ...
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Electrical characteristics 6.4 Supply current characteristics Table 24. Supply current characteristics Symbol Parameter Average suppy current I (FR) DD Free Run mode I DD Average suppy current (Sleep 100ms Sleep mode 100ms Average suppy current (Sleep 500ms Sleep ...
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QST104 6.5 Capacitive sensing characteristics Table 25. External sensing components Symbol C Sense capacitor S C Equivalent electrode capacitor X C Equivalent touch capacitor T R Serial resistance S Table 26. Capacitive sensing parameters Symbol t Calibration duration CAL t ...
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Electrical characteristics 6.6 KOUTn/OPTn/GPOn pin characteristics 6.6.1 General characteristics Subject to general operating conditions for V Table 27. 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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QST104 Figure 9. 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 15. Typical Pins DD OH load DD 800 -40°C 700 25°C 85°C 600 125°C 500 400 300 200 100 0 2 ...
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QST104 6.7 RESET pin T = -40°C to 125°C, unless otherwise specified. A Table 29. RESET pin characteristics Symbol V Input low level voltage IL V Input high level voltage IH Schmitt trigger voltage V hys hysteresis Output low level ...
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Electrical characteristics control interface 6.8 Subject to general operating conditions for V 2 The QST104 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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QST104 Figure 20. Typical application with I 4.7kΩ BUS START SDA t f(SDA) SCL t t h(STA) w(SCKH bus and timing diagram 4.7kΩ 100Ω SDA 100Ω SCL t r(SDA ...
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Package mechanical data 7 Package mechanical data Figure 21. 32-pin low profile quad flat package (7x7) outline Seating plane Pin 1 identification 40/ ccc ...
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QST104 Table 32. 32-pin low profile quad flat package mechanical data Dim ccc 1. Values in inches are converted from mm and rounded to 4 ...
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Part numbering 8 Part numbering Table 33. Ordering information scheme Example: Device type QST = Capacitive touch sensor Device sub-family 1: QTouch ( Channel count Number of channels Pin count K: 32 pins Package T: LQFP (thin ...
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QST104 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 22. Device revision identification (TQFP package) Table 34. Device ...
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Revision history 10 Revision history Table 35. Document revision history Date 26-Nov-2007 5-Feb-2008 44/45 Revision 1 Initial release. 2 Upgraded document status to datasheet. QST104 Changes ...
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... QST104 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. ...