QT60161
`16 Key QMatrix™ Keypaner Sensor IC
`
`
`Advanced second generation QMatrix controller
`°
`seein
`28838
`52,
`
`@ 16 touch keys through anydielectric
`epemamess og ss
`
`@ 100% autocalforlife -no adjustments required
`Hoan AE oo
`
`
`
`
`
`® SPI Slave or Master/Slave interface to a host controller
`mos! 144 48 42 41 40 39 38 37 36 35 3),soa
`
`@ Parallel scan interface for electromechanical compatibility
`™'Ss° '—2
`32 /— CS2B
`.
`2
`os
`.
`ays
`os
`=
`sckK [13
`31 [= CS3A
`
`
`@ Keys individually adjustable for sensitivity, response time,=,.., __|, 30 csp
`
`and many othercritical parameters
`Vdd Co] 5
`OT60161
`29 = Aref
`@ Sleep mode with wake pin
`vss (46
`TOQFP-44
`28 = AGnd
`.
`.
`XTO C17
`27 = AVdd
`@ Synchronous noise suppression
`xt ls
`26KYsa
`@® Mix and match key sizes & shapes in one panel
`RX 9
`25YS2
`® Adjacent key suppression feature
`we i” ©
`* [_ ven
`@ Panel thicknesses to 5 cm or more
`“2 13 14 18 16 17 18 19 20 2122 |”
`@ Low overhead communications protocol
`,
`J
`i, J | J J . ,
`@ 44-pin TQFP package
`s g g ~ Se 8SZLNG
`
`
`
`
`
`
`APPLICATIONS-
`
`* Security keypanels
`e Industrial keyboards
`
`« Appliance controls
`¢ Outdoor keypads
`
`« ATM machines
`¢ Touch-screens
`
`¢ Automotive panels
`e Machine tools
`
`The QT60161 digital charge-transfer (“QT”) QMatrix™IC is designed to detect human touch on up 16 keys when usedin
`conjunction with a scanned, passive X-Y matrix. It will project the keys through almost any dielectric, e.g. glass, plastic, stone,
`ceramic, and even wood, up to thicknesses of 5 cm or more. The touch areas are defined as simple 2-part interdigitated
`electrodes of conductive material, like copper or screened silver or carbon deposited on the rear of a control panel. Key sizes,
`shapes and placementare almostentirely arbitrary; sizes and shapes of keys can be mixed within a single panel of keys and can
`vary by a factor of 20:1 in surface area. The sensitivity of each key can besetindivicually via simple functions over the SPI or
`UARTport, for example via Quantum’s QmBtn program, or from a host microcontroller. Key setups are stored in an onboard
`eeprom and do not need to be reloaded with each powerup.
`
`The device is designed specifically for appliances, electronic kiosks, security panels, portable instruments, machine tools, or
`similar products that are subject to environmental influences or even vandalism. It can permit the construction of 100% sealed,
`watertight control panels that are immune to humidity, temperature, dirt accumulation, or the physical deterioration of the panel
`surface from abrasion, chemicals, or abuse. To this end the device contains Quantum-pioneered adaptive auto self-calibratian,
`drift compensation, and digital filtering algorithms that make the sensing function robust and survivable.
`
`The part can scan matrix touch keys over LCD panels or other displays when used with clear ITO electrodes arranged in a matrix.
`It does not require ‘chip on glass’ or other exotic fabrication techniques, thus allowing the OEM to source the matrix from multiple
`vendors. Materials such as such common PCB materials or flex circuits can be used.
`
`External circuitry consists of a resonator and a few capacitors and resistors, all of which can fit into a footprint of less than 6 sq. cm
`(1 sq. in). Control and data transferis via either a SPI or UARTport; a parallel scan port provides backwards compatibility with
`scanned electromechanical keys.
`
`The QT60161 makesuse of an important new variant of charge-transfer sensing, transverse charge-transfer, in a matrix format
`that minimizes the number of required scan lines. Unlike some older technologies it does not require one sensing IC per key.
`
`AVAILABLE OPTIONS
`TOFP Part Number
`OT60161-S
`QT60161-AS
`
`O'C to +70°C
`-A0°C to +105°C
`
`g,
`4 QUANTUM
`
`Copyright © 2001 Quantum Research Group Ltd
`Pat Pend. R1.01/02.02
`
`Petitioners Samsung and Sony Ex-1021, 0001
`1193RESP_00003827
`
`Petitioners Samsung and Sony Ex-1021, 0001
`
`

`

`®Quantum Research Group Ltd.
`
`Contents
`y Ox79- Column Keys SCOPE LLL eee 18
`{Overview .. 0... cette eee 4
`5.5 Status COMMANGS 1...ee ee 18
`1.1 Field FIOWS 2. cece eee eee te eeeeees 4
`O Ox30- Signal FOr SINGIG KEY Lc eee 18
`1.2 CIFCUIE OVEFVIOW oo. e cee teene eee 4
`7
`0x31 - Delta Signal for Single Key ok eee 18
`T3CoOMMuNIcations
`....Le eet 4
`2 OK32-REFEFENCE VANE eee 18
`2 Signal Processing ............0 000 c ccc e eee e cence 5
`
`2.1 Negative Threshold 2.0... ccc ccc ccc cee cece eeeees 5 0x35-Detection integrator Counts ..... 1.22. ee 185
`
`2.2 Positive Threshold oo... ccc eens 5
`6 Ox36-Eeprom Checksum ©... es 18
`23 Hysteresis 0000. ee eee eee eee 5
`7 OX37- General Device Status 96 ce eee 49
`24 Drift Compensation ......... 0.0.0.0 ccc eee eee 5
`<sp> Ox20- Signal Levels For GrOUD oe ec eee 19
`2.5 Negative Recalibration Delay
`........................ 6
`1
`0x21 - Delta Signals FOrGFOUD de ee ee 19
`2.6 Detection Integrator 2.0... .. 0. eee eee eee 6
`Ox22 - Reference Levels FOF CFOUD ©. kk eee ee eee 19
`2.7 Positive Recalibration Delay
`............ 000 eee ee eens 6
`% Ox25- Detect integrator Counts for Croud
`... Le ee 19
`
`2.8 Signal and Reference Guardbanding 0x65-Error Code for Selected KeY ee 19..............006. 6 @
`
`
`2.9 Adjacent Key SUPPFeSSION 2.6... eee ees 7
`E OxAS- Error Codes FOF GOUD we ee es 20
`2.10 FullRecalioration .. 0... ccc cece cee teen ees 7
`k OX6B- Reporting of First Touched Key |... ee 20
`2.11 Device Status &ReEPOrting 2... eee eee 7
`5.4Setup Commands
`............0..0 0.00222 21
`3 Circuit Operation ....0..0.0 00.0 c cece cece cence nee nees 7
`“A 0x01- Negative Detect Threshold |. . 6... ee eee eee ee 24
`3.1 Matrix Scan Sequence 20... eee ee 7
`“B Ox02- Positive Detect Threshold 1.6... keke ee 21
`32 Signal Path 00. oo ccc cece eee eee beeen ene eeennue 8
`*€
`0x03 - Negative Threshold Hysteresis » oo ke ww 21
`3.3K Electrode Drives
`.......0..0. 0c eee eee eee enue 8
`“D OKXO04 - Positive Threshold Hysteresis dk tc ee we ee 21
`BRIRFPrOMXLINGS ccc a cucusnavanres 8
`“F OXOG-BUPSELONOTN ccc eens 21
`3.3.2 Noise Coupling Into XIIN@S od ccc ene neues 8
`“G OXO7- BUISE SPACING eee ee eee 22
`B.4'Y' Gate DIVES 200e ee e eee 8
`“H 0x08 - Negative Drift Compensation Rate 5 ............. 22
`BATREPFFOMY LINES oo ccc ccc uucueuvuvunvuvugs 8
`*f OxO9 - Positive Drift Compensation Rat€ ke 22
`3.4.2 Noise Coupling Into Y LINES 20 ccc ccc ccccuce 8
`“J OxOA - Negative Detect integrator Limit
`...0.. ole 22
`3.5 Burst Length &Sensitivity ................00.-00ee eee 8
`“K OxOB- Positive Recalibration Delay) 6... kee ees 23
`3.6 Burst Acquisition Duration... 000.0. cece eee eee es 9
`“L Ox0C - Negative Recalibration Delay oii cee eee 23
`3.7 IntraBurst Spacing 2. cc eee eee 9
`“M OxOD - intra-Burst Puls Spacing kee 23
`3.8 Burst Spacing Deke bbb bbe bb bebe bbe bebebbbeebbennee 9
`“N OXOE - Positive Reference ErrorBand » oo... lke wc eens 23
`3.9Sample Capacitors 6.0... eee eee ee eee aee 9
`“O OXOF - Negative Reference ErrorBande
`©. 6... kee ee 23
`3.10 Water FiIM Suppression 20... 0... c cece eee eee eae 9
`“P Ox10- Adjacent Key SUDPFESSION 0... ecw ween ee 24
`BAT RESCCINDUC 00. ccc cece cece ee eeeeteeteeues 9
`5.5 Supervisory / System Functions wo... . cc eee eee 24
`BAZ OSCINACOF oe cece eee eee teenies 9
`6 OX36- EEDKOM CHECKSUM cee eee 24
`3.13 Startup / Calibration TIMES 6... eee ee ee 9
`£ OxdC- tock Reference Levels ccc ee 24
`3.14 SleepWake / Noise Sync Pin WS) 6... cee 0
`b Ox62-Recalibrate Kevs ©... eee 24
`BAS LED/AlertQutput 2.0... ccc eee eee eee 11
`f Ox6C - Return Last Command Character ©1611... ee eee 25
`3.16 Oscilloscope SYNC 22... cece eee eee
`11
`F OX7Z-ROSCEEDOVICE Lies 25
`3.17 Power Supply & PCB Layout ....................0.. 14
`Vo OXSG- RELUIN Part VEFSION . oo eee 25
`3.18 ESD / Noise Considerations
`....................6-.
`1
`W Ox57- Return Part Signature eee 25
`4 Communications Interfaces ....................-..--- 12
`Z OXSA-ENTErSICCD eens 25
`4.4 Serial Protocol Overview 2.0.00. c ccc cece cce ence
`2
`“Q Oxt1- Data Rate Selection 261... eet e eee ee eee 25
`4.2 SPI Port Specifications ......... 00.0. cece eee eee 12
`*R OX12 = OSCHOSCOPE SYNE LL kee ee eee 26
`ABSPISlavVe-Only MOdE 0.0... ieee cece eee eevee 12
`“We OXT7- NOISE SYNCeee 26
`4ASPI Master-Slave MOd@ oo... ceeeee eee
`3
`5.6 Function Summary Table 2.1... eee eee eee 27
`AS UART Interface oo... ieee ccc eee e eee 5
`5.7 Timing Limitations
`................. 0-2. e eee 30
`
`4.6 Sensor Echo and Data Response ...........0 eee 15||6 Electrical Specifications ...................-....+--- 31
`47? ParalielScan Port 2.000.000.0000. cc cece eee eee aee 15
`6.1 Absolute Maximum Specifications 2... 0... ees 31
`A8Eeprom Corruption ....... 00.0 cece cece eees
`6
`6.2 Recommended operating conditions
`...........000.
`31
`5 Commands & Functions ...............0 cc cccccccceee 17
`6.3 DC Specifications .. 0.0... ce eee 31
`5.1 Direction Commands ...........---ecceecccccecces
`7
`G.4PVOTOCOI TIMING 2.0... cee ee ee eee 31
`Q OxX67-GetCommand
`|... 6... cece ccc cc cccucucs 17
`6.5 Maximum Drdy Response Delays ........ 0.000 cee eee 32
`Pp OX70-PutCOmMMAaNd «ddd cence ee senvnes
`17
`7 Mechanical 2.0.0.0... eee eee 33
`5.2Scope Commands ...... ccc ccc ccc cee ewes 18
`T.TDIMENSIONS 2... eens 33
`S OX73-Specific Key SCOPE «od ccc cue ueuuues
`8
`T2QAMAPKING 2... ce eee ene 33
`S OX53-AKEYSSCOPE ©. ccc cc cccuccuuccucees
`8
`Bindex Loo eee ee eee eee eens 34
`X OX7B-ROW KEYS SCOPE eee ees
`
`18
`
`
`Y QUANTUM
`ii
`www.gprox.com QT601671/RT1.01
`RESEARCH GROUP
`
`Petitioners Samsung and Sony Ex-1021, 0002
`1193RESP_00003828
`
`Petitioners Samsung and Sony Ex-1021, 0002
`
`

`

`®Quantum Research Group Ltd.
`
`
`
`
`
`
`Table 1.1 Device Pin List
`
`Pin Name|Type|Description
`
`Master-Out / Slave In SPI line. In Master/Slave SPI mode is used for both communication directions.
`1
`MOSI
`1/0 PP
`:
`:
`a
`
`In Slave SPI modeis the data input (in only).
`Master-In / Slave Out SPI line. Not used in Master/Slave SPI made.
`2
`MISO
`vO PP
`In Slave mode outputs data to host (out only).
`
`3 1/O PP|SPI Clock. In Master mode is an output; in Slave mode is an inputSCK
`
`
`
`4
`RST
`|
`Resetinput, active low reset
`
`5
`Vdd
`Pwr
`+5V supply
`
`6
`Vss
`Pwr
`Ground
`
`7
`XTO
`O PP
`Oscillator drive output. Connect to resonatoror crystal.ply
`
`8
`XTI
`|
`Oscillator crive input. Connect to resonatoror crystal, or external clock source.
`
`9
`RX
`|
`UARTreceive input
`10
`TX
`O PP
`UARTtransmit output
`
`1
`WS
`|
`Wake from Sleep / Sync to noise source
`
`12
`SMP
`O PP
`Sample output control
`
`13
`XOOPA
`/O PP
`X0 Drive matrix scan / Communications option A input
`
`14
`X1OPB
`1/0 PP 1 Drive matrix scan / Communications option B input
`
`15
`X2
`O PP
`X2 Drive matrix scan
`
`16
`x3
`O PP
`X3 Drive mairix scan
`
`17
`Vdd
`Pwr
`+5V supply
`
`18
`Vss
`Pwr
`Ground
`
`19
`XSO
`|
`XSO0 Scan inputline
`
`20
`xXS1
`|
`XS1 Scan inputline
`
`21
`XS2
`|
`XS2 Scan inputline
`
`22
`X83
`|
`X$3 Scan inputline
`
`23
`YSO
`O PP
`¥SO Scan output line
`
`24
`YS1
`O PP
`YS1 Scan output line
`
`25
`YS2
`O PP
`YS2 Scan output line
`
`26
`YS3
`O PP
`YS3 Scan output line
`
`27
`AVdd
`Pwr
`+5 supply for analog sections
`
`28
`AGnd
`Pwr
`Analog ground
`
`29
`Aref
`Pwr
`+5 supply for analog sections
`
`30
`CS3B
`1/0 PP
`Cs3 control B
`
`31
`CS3A
`1/0 PP
`Cs3 control A
`
`32
`CS2B
`1/O PP
`Cs2 control B
`
`33
`CS2A
`1/0 PP
`Cs2 control A
`
`34
`CS1iB
`1/0 PP
`Csi control B
`
`35
`CS1A
`1/0 PP
`Csi control A
`
`36
`CSOB
`1/O PP
`Cs0 control B
`
`37
`CSO0A
`1/0 PP
`Cs0 control A
`
`38
`Vdd
`Pwr
`+5 supply
`
`39
`Vss
`Pwr
`Ground
`
`40
`LED
`O PP
`Active low LED status drive / Activity indicator
`
`41
`DRDY
`00D Data ready output for Slave SPI mode; active low
`
`42
`Vref
`|
`Vref input for conversion reference
`43
`sO
`O PP
`Oscilloscope sync output
`44
`Ss
`VO OD
`Slave select for SPI direction control; active low
`
`VO:
`
`| = Input
`O = Output
`Pwr = Powerpin
`/O = Bidirectional line
`PP = Push Pull output drive
`OD = Opendrain output drive
`
`
`& QUANTUM
`iii
`www.gprox.com QT60167/R1.01
`RESEARCH GROUP
`
`Petitioners Samsung and Sony Ex-1021, 0003
`1193RESP_00003829
`
`Petitioners Samsung and Sony Ex-1021, 0003
`
`

`

`®Quantum Research Group Ltd.
`
`1 Overview
`QMatrix devices are digital burst mode charge-transfer (QT}
`sensors designed specifically for matrix geometry touch
`controls; they include all signal processing functions
`necessary to provide stable sensing undera wide variety of
`changing conditions. Only a few low cost external parts are
`required for operation. The entire circuit can be built in under
`6 square centimeters of PCB area.
`
`Figure 1-1 Field flow between X and Y elements
`
`element
`
`element
`
`
`
`cmos
`driver
`
`“JLIL-
`
`Figure 1-4 Sample Electrode Geometries
`
`PARALLEL LINES
`
`SERPENTINE
`
`SPIRAL
`
`charge driven by the X electrode is partly received onto the
`corresponding Y electrode which is then processed. The part
`uses 4 'X' edge-driven rows and 4 'Y' sense columns to sense
`up to 16 keys.
`
`The charge flows are absorbed by the touch of a human
`finger (Figure 1-1) resulting in a decrease in coupling from X
`to Y. Thus, received signals decrease or go negative with
`respect to the reference level during a touch.
`
`As shownin Figure 1-3, waterfilms cause the coupled fields
`to increase slightly, making them easyto distinguish from
`touch.
`
`The device has a wide dynamic range that allows for a wide
`variety of key sizes and shapes to be mixed together in a
`single touch panel. These features permit new types of
`keypad features such as iouch-sliders, back-illuminated keys,
`and complex warped panels.
`
`The devices use an SPI interface running at up to 3MHz rates
`to allow key data to be extracted and to permit individual key
`parameter setup, or, a UART port which can run atrates to
`57.6 Kbaud. The serial interface protocol uses simple
`commands; the command structure is designed to minimize
`the amount of data traffic while maximizing the amount of
`information conveyed.
`
`1.2 Circuit Overview
`A basic circuit diagram is shown in Figure 1-5. The ‘X’ drives
`are sequentially pulsed in groupings of bursts. At the
`intersection of each ‘X’ and ‘Y’line in the matrix itself, where
`a key is desired, should be an interdigitated electrode set
`similar to those shownin Figure 1-4. Consult Quantum for
`application assistance on key design.
`
`The device uses fixed external capacitors to acquire charge
`from the matrix during a burst of charge-transfer cycles; the
`burst length can be varied to permit digitally variable key
`signal gains. The charge is converted to digital using a
`single-slope conversion process.
`
`In addition to normal operating and
`setup functions the device can also
`report back actual signal strengths
`and error codes over the serial
`interfaces.
`
`QmBin software for the PC can be
`used to program the IC as well as
`read back key status and signal
`levels in real time.
`
`A parallel scan port is also provided
`that can be used to directly replace
`membrane type keypads.
`
`QMatrix technology employs
`transverse charge-transfer (‘QT’)
`sensing, a new technologythat
`senses the changesin an electrical
`charge forced across an electrode
`set.
`
`1.1 Field Flows
`Figure 1-1 shows how charge is
`transferred across an electrode set
`to permeate the overlying panel
`material; this charge flow exhibits a
`high dQ/dt during the edge
`transitions of the X drive pulse. The
`
`Figure 1-2 Field Flows When Touched
`
`
`l Keelement Felement
`
`ash ig
`epee23
`Sy
`SasVe
`
`WATSper
`
`cverying panel
`
`cmos
`driver
`
`Figure 1-3 Fields With a Conductive Film
`
`Water film
`
`
`
`Burst mode operation permits the
`use of a passive matrix, reduces RF
`emissions, and provides excellent
`responsetimes.
`Refer to Section 3 for more details
`on circuit operation.
`
`1.3 Communications
`The device uses two variants of SPI
`communications, Slave-only and
`Masier-Slave, a UARTinterface,
`plus a parallel scan interface. Over
`the serial interfaces are used a
`command and data transfer
`structure designed for high levels of
`flexibility using minimal numbers of
`bytes. For more information see
`Sections 4 and 5.
`
`The parallel scan port permits the
`replacement of electromechanical
`keypads that would be scanned by
`a microcontroller; the scan interface
`mimics an electromechanical
`keyboara’s response.
`
`
`
`~~ QUANTUM
`oe RESEARCH GROUP
`
`www.qprox.com QT60167/R1.07
`
`Petitioners Samsung and Sony Ex-1021, 0004
`1193RESP_00003830
`
`Petitioners Samsung and Sony Ex-1021, 0004
`
`

`

`®Quantum Research Group Ltd.
`
`Figure 1-5 Circuit Block Diagram
`Vv
`
`<oee Leee-[>
`
`QT60161
`
`YOY1 Y2 Y3
`
`
`ScanOutput
`
`ScanInout
`
`2 Signal Processing
`The device calibrates and processes signals using a number
`of algorithms specifically designed to provide for high
`survivability in the face of adverse environmental challenges.
`The QT60161 provides a large numberof processing options
`which can be user-selected to implement very flexible, robust
`keypanel solutions.
`
`2.1 Negative Threshold
`See also command *A, page 27
`
`The negative threshold value is established relative to a key's
`signal reference value. The threshold is used to determine
`key touch when crossed by a negative-going signal swing
`after having been filtered by the detection integrator (Section
`2.6). Larger absolute values of threshold desensitize keys
`since the signal musttravel farther in order to cross the
`threshold level. Conversely, lower thresholds make keys
`more sensitive.
`
`As Cx and Cs drift, the reference point drift-compensatesfor
`these changesat a user-settable rate (Section 2.4); the
`threshold level is recomputed whenever the
`reference point moves, and thusit also is drift
`compensated.
`
`The threshold is user-programmed using the setup process
`described in Section 5 on a per-key basis.
`
`2.3 Hysteresis
`See also command *C and *D, page 27
`
`KEYMATRIX
`
`Refer to Figure 1-6. The QT60161 employs programmable
`hysteresis levels of 12.5%, 25%, or 50% of the delta between
`the reference and threshold levels. There are different
`hysteresis settings for positive and negative thresholds which
`can be set by the user. The percentagerefers to the distance
`between the reference level and the threshold at which the
`detection will drop out. A percentage of 12.5% is less
`hysteresis than 25%, and the 12.5% hysteresis point is closer
`to the threshold level than to the reference level.
`
`The hysteresis levels are set for all keys only; it is not
`possible to set the hysteresis differently from key to key on
`either the positive or negative hysteresis levels.
`
`2.4 Drift Compensation
`See also commands *H, *I, page 22
`
`Signal levels can drift because of changes in Cx and Cs over
`time. It is crucial that such drift be compensated, else false
`detections, non- detections, and sensitivity shifts will follow.
`The QT60161 can compensate for drift using two setups, “H
`and Al.
`
`Drift compensation is performed by making the reference
`level track the raw signal at a slow rate, but only while there is
`no detection in effect. The rate of adjustment must be
`performed slowly, otherwise legitimate detections could be
`ignored. The devices drift compensate using a slew-rate
`limited change to the reference level; the threshold and
`hysteresis values are slaved to this reference.
`
`When a finger is sensed, the signal falls since the human
`body acts to absorb charge from the cross-coupling between
`X and Y lines. An isolated, untouched foreign object (a coin,
`or a waiter film) will cause the signal to rise very slightly due to
`the enhanced coupling thus created. These effects are
`contrary to the way most capacitive sensors operate.
`
`Once a finger is sensed, the drift compensation mechanism
`ceases since the signal is legitimately detecting an object.
`Drift compensation only works when the key signalin
`question has not crossed the negative threshold level
`(Section 2.1).
`
`The drift compensation mechanism can be made asymmetric
`if desired; the drift-compensation can be made to occur in
`one direction faster than it does in the other simply by setting
`4H and “Il to different settings.
`
`Figure 1-6 Detection and Drift Compensation
`
`The threshold is user-programmed on a per-key
`basis using the setup process (Section 5).
`
`2.2 Positive Threshold
`See also command “B, page 27
`
`The positive threshold is used to provide a
`mechanism for recalibration of the reference point
`when a key's signal moves abrupily to the positive.
`Thesetransitions are described morefully in
`Section 2.7.
`
`/ Reference
`
`Signal”
`
`
`
`www.qprox.com QT60167/R1.07
`
`Petitioners Samsung and Sony Ex-1021, 0005
`1193RESP_00003831
`
`Petitioners Samsung and Sony Ex-1021, 0005
`
`

`

`®Quantum Research Group Ltd.
`
`Drift compensation should usually be set to compensate
`faster for increasing signals than for decreasing signals.
`Decreasing signals should not be compensated quickly, since
`an approaching finger could be compensatedfor partially or
`entirely before even touching the touch pad. However, an
`obstruction over the sense pad, for which the sensor has
`already madefull allowance for, could suddenly be removed
`leaving the sensor with an artificially suppressed reference
`level and thus becomeinsensitive to touch. In this case, the
`sensor should compensate for the object's removal by raising
`the reference level quickly.
`
`The drift compensation rate can be set for each key
`individually, and can also be disabled completely if desired on
`a per-key basis.
`
`Drift compensation and the detection time-outs (Section 2.5}
`work together to provide for robust, adaptive sensing. The
`time-outs provide abrupt changesin reference location
`depending on the duration of the signal ‘event’.
`
`2.5 Negative Recalibration Delay
`See also command “L, page 23
`
`If a foreign object contacts a key the key's signal may change
`enough in the negative direction, the same as a normal
`touch, to create an unintended detection. When this happens
`it is usually desirable to cause the key to be recalibrated in
`orderto restore its function after a time delay of some
`seconds.
`
`The Negative Recal Delay timer monitors this detection
`duration; if a detection event exceeds the timer's setting, the
`key will be recalibrated so that it can function thereafter. The
`AL function can be altered on a key by key basis. It can be
`disabled if desired by setting the *L parameterto zero, so that
`it will never recalibrate automatically.
`
`2.6 Detection Integrator
`See also command “J, page 22
`
`2.7 Positive Recalibration Delay
`See also command *K, page 23
`
`A recalibration can occur automatically if the signal swings
`more positive than the positive threshold level. This condition
`can occur if there is positive drift but insufficient positive drift
`compensation, or if the reference moved negative due te a
`recalibration, and thereafter the signal returned to normal.
`
`As an example ofthe fatter, if a foreign object or a finger
`contacts a key for period longer than the Negative Recal
`Delay, the key is recalibrated to a new lower referencelevel.
`Then, when the condition causing the negative swing ceases
`to exist (e.g. the object is removed) the signal can suddenly
`swing backpositive to near its normal reference.
`
`It is almost always desirable in these cases to cause the key
`to recalibrate to the new signal level so as to restore normal
`touch operation. The device accomplishes this by simply
`setting Reference = Signal.
`
`The time required to detect this condition before recalibrating
`is governed by the Positive Recalibration Delay command. In
`order for this feature to operate, the signal mustrise through
`the positive threshold level (Section 2.2) for the proscribed
`interval determined by Setup *K.
`
`After the Positive Recal Delay interval has expired and the
`fast-recalibratian has taken place, the affected key will once
`again function normally. This interval can be set on a per-key
`basis; it can also be disabled by setting *K to zero.
`
`2.8 Signal and Reference Guardbanding
`See also commands 4N, *O, page 23; ‘L’, page 24
`
`The QT60161 provides for a method of self-checking that
`allows the host to ascertain whether one or more key signals
`or reference levels are ‘out of spec’. This feature can be used
`to determine if an X or Y line has broken, the matrix panel
`has delaminated from the control panel, or there is a circuit
`fault. There are two kinds of guardbands, but both report
`using the same twoerrorflags.
`
`To suppressfalse detections caused by spurious eventslike
`Signal guardbanding aleris the host via an error flag if the
`electrical noise, the QT60xxd5 incorporates a ‘detection
`raw signal of a key falls below 64 or rises above 65,471. Bits
`integrator’ counter that increments with each detection
`2 or 3 of function ‘e' will be set for keys whose signals are
`sample until a user-defined limit is reached, at which point a
`outside of those limits. The error will also appear inabitfield
`detection is confirmed. if no detection is sensed on any of the
`reported via command 'E’.
`samplesprior to the final count, the counter is reset
`immediately to zero, forcing the processto restart.
`
`When an active key is released, the counter must count down
`to zero before the key state is set to ‘off’. Setting a key’s
`detection integrator target value to zero disables that key
`although the bursts for that key continue normally.
`
`The detection integrator is extremely effective at reducing
`false detections at the expense of slower reaction times. In
`some applications a slow reaction time is desirable; the
`detection integrator can be used to intentionally slow down
`touch response in orderto require the user to touch longerto
`operate the key.
`
`There are 16 possible values for this function.
`
`Reference guardbanding alerts the host when the reference
`level of a key falls outside of user-defined levels which can be
`much narrower than the signal guardbanding. The reference
`guardband is determined as a percent deviation from the
`‘tocked' reference level of each individual key. The signal
`reference levels can be stored into internal eeprom via the
`Leck command 'L' during production; deviations in reference
`levels that fall outside the guardbands centered on these
`locked reference levels are then reported as errors.
`
`The guardband can be setdifferently for each signal direction
`relative to the stored and lockedlevels. The possible settings
`are from 0.1% to 25.5% of signal reference in steps of 0.1%
`as set by commands “N (positive swings) and *O (negative
`swings). A setting of 0 (zero) disables the corresponding
`guardband direction.
`
`Once the L command hasrecorded all values of signal
`reference into eeprom, and if guardbanding is enabled, the
`part will compare the actual reference level of each keyto its
`corresponding guardbandsto seeifit falls outside of these
`
`
`
`www.qprox.com QT60167/R1.07
`
`Petitioners Samsung and Sony Ex-1021, 0006
`1193RESP_00003832
`
`Petitioners Samsung and Sony Ex-1021, 0006
`
`

`

`limits. If so, either of bits 2 and 3 of command 'e' will be set
`for that key. The error will also appear in a bitfield reported
`via command 'E'.
`
`2.9 Adjacent Key Suppression
`See aiso command *P, page 24
`
`The QT60141 incorporates adjacent key suppression that can
`be enabled on a per-key basis. This feature permits the
`suppression of multiple key presses based on relative signal
`strengths. This feature assists in solving the problem of
`surface water which can bridge a key touch to an adjacent
`key, causing multiple key presses. This feature is also useful
`for panels with tightly spaced keys, where a fingertip can
`partially overlap an adjacent key. This feature will act to
`suppress the signals from the unintended key(s).
`
`Adjacent key suppression works for keys across the entire
`panel and is not restricted to physically adjacent keys; the
`device has no knowledge of which keys are physically
`adjacent. When enabled for a key, adjacent key suppression
`causes detections on that key to be suppressed if any other
`key in the panel has a more negative signal deviation from its
`reference, even if the other key does not have adjacent key
`suppression enabled.
`
`This feature does not account for varying key gains (burst
`length) but ignores the actual negative detection threshold
`setting for the key. If keys in a panel have differentsizes, it
`may be necessary to reduce the gains cflarger keys relative
`to smailer ones to equalize the effects of adjacent key
`suppression. The signal threshold of the larger keys can be
`altered to compensatefor this without causing problems with
`key suppression.
`
`Adjacent key suppression works to augment the natural
`moisture suppression capabilities of the device (Section
`3.10), creating a more robust sensing method.
`
`2.10 Full Recalibration
`See also command ‘b’, page 24
`
`The part fully recalibrates one or more keys after the ‘b’
`command has been issued toit, depending on the current
`scope of the ‘b’ command. The device recalibrates all keys on
`powerup, after a hard reset via the RST pin or on power up,
`or via a reset using the ‘r’ command. Since the circuit
`tolerates a very wide dynamic signal range, it is capable of
`adapting to a wide mix of key sizes and shapes having widely
`varying Cx coupling capacitances.
`
`lf a false calibration occurs due to a key touch orforeign
`object on the keys during powerup, the affected key will
`recalibrate again when the object is removed depending on
`the settings of Positive Threshold and Positive Recal Delay
`(Sections 2.2 and 2.7).
`
`Calibration requires 9 full burst cycles to complete, and so the
`time it takes is dependent on the burst spacing parameter
`(Section 3.8 also, “G, page 22.
`
`®Quantum Research Group Ltd.
`
`2.11 Device Status & Reporting
`
`See also commands ‘7’, page 19; ‘e’, page 19; °E’, page 20;
`‘k’, page 20, ‘K’, page 20
`
`The device can report on the general device status or specific
`key states including touches and error conditions, depending
`on the command used.
`
`Usually it is most efficient to periodically request the general
`device status using command ‘7’first, as the responseto this
`command is a single byte which reports back on behalf of all
`keys. ‘7’ indicates if there are any keys detecting, calibrating,
`or in error.
`
`If command ‘7’ reports a condition requiring further
`investigation, the host device can then use commands ‘e’, ‘E’,
`‘k’ or ‘K’ to provide further details of the event(s) in progress.
`This hierarchical approach provides for a concise information
`flow using minimal data transfers and low host software
`overhead.
`
`3 Circuit Operation
`A QT60161 referencecircuit is shown in Figure 2-1.
`
`3.1 Matrix Scan Sequence
`The circuit operates by scanning each key sequentially, key
`by key. Key scanning begins with location X=0 / Y=0. X axis
`keys are known as rows while Y axis keys are referred to as
`columns. Keys are scanned sequentially by row, for example
`the sequence YOXO YOX1 YOX2 YOX3 Y1X0etc.
`
`Each key is sampled from 1 to 64 times in a burst whose
`length is determined by Setup “F. A burst is completed
`entirely before the next key is sampled; at the end of each
`burst the resulting analog signal is converted to digital using a
`single-slope conversion process. The length of the burst
`directly impacts on the gain of the key; each key can have a
`unique burst length in order to allow tailoring of key sensitivity
`on a key by keybasis.
`
`''''
`tti
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`t''tt'‘''
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`t
`
`Start
`
`Figure 3-1 QT60161 Circuit Model
`eon anew e eee eee'
`X drive
`(1 of 4)
`
`Xx
`
`x
`electrode
`
`electrode
`
`Y line (1 of 4)
`
`Single-slope14bitADC
`
`‘SMP
`
`
`
`www.qprox.com QT60167/R1.07
`
`Petitioners Samsung and Sony Ex-1021, 0007
`1193RESP_00003833
`
`Petitioners Samsung and Sony Ex-1021, 0007
`
`

`

`®Quantum Research Group Ltd.
`
`3.2 Signal Path
`Refer to Figures 1-5, 3-1, and 3-2.
`
`X-Drives. The X drives are push-pull CMOSlines which drive
`charge through the matrix keys on the positive and negative
`edges of X. Only the positive edge of X is used for signal
`purposes, however the negative edge must cause the charge
`across the keys to neutralize prior to the next positive edge,
`else the sampling mechanism will cease after one pulse. The
`part accomplishes this by holding all Y lines to ground during
`the falling edge of X.
`
`Charge gate. Only one X row is pulsed during a burst.
`Charge is coupled across a key's Cx capacitance from the X
`row to all Y columns. A particular key is chosen by gating the
`charge from a single Y column into a single one of four
`possible sampler capacitors. The other three X and three Y
`lines are clamped to ground during this process.
`
`Dwell time. The dwell time is determined internally and is
`the same as one oscillator pericd, i.e. 83.3ns with a 12MHz
`resonator. The dwell time is set via internal switching action
`which limits the interval during which charge can be accepted
`by a Cs capacitor after the rise of an X driveline.
`
`Dwell time has a cramatic effect on the suppression of
`moisture films as described in Section 3.10.
`
`Cs Charge Integrator capacitor. The Cs capacitors
`integrate charge arriving through the matrix keys' Cx
`capacitances, correspondent with the rise of X; to do this a
`switching arrangement on the Cs control pins permits the
`charge to accumulate so that the B side of the Cs capacitors
`becomes negativ