sx8649 Semtech Corporation, sx8649 Datasheet
sx8649
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sx8649 Summary of contents
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... ADVANCED COMMUNICATIONS & SENSING G D ENERAL ESCRIPTION The SX8649 is an ultra low power, fully integrated 8- channel solution for capacitive touch-buttons and wheel applications. Unlike many capacitive touch solutions, the SX8649 features dedicated capacitive sense inputs (that requires no external components) in addition to 8 general purpose I/O ports (GPIO). ...
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... Software Reset 3.15 Interrupt 3.15.1 Power up 3.15.2 Assertion 3.15.3 Clearing Revision 7_6, February 10 Ultra Low Power, Capacitive Button and Wheel Touch Controller (8 sensors) with Enhanced LED Drivers Table of Contents ............................................................................................................ 1 ............................................................................................................... 4 ................................................................................................. 7 ........................................................................................................ 10 © 2010 Semtech Corp. 2 SX8649 DATASHEET ...
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... NFORMATION ACKAGING NFORMATION 8.1 Package Outline Drawing 8.2 Land Pattern Revision 7_6, February 10 Ultra Low Power, Capacitive Button and Wheel Touch Controller (8 sensors) with Enhanced LED Drivers .............................................................................. 38 ...................................................................................................... 75 ........................................................................................................ 76 © 2010 Semtech Corp. 3 SX8649 DATASHEET ...
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... Pinout Diagram Figure 1 8649 yyww xxxxx R05 yyww = Date Code xxxxx = Semtech lot number R05 = Semtech Code Marking Information Figure 2 © 2010 Semtech Corp. 4 DATASHEET 22 21 gnd 20 gpio5 19 gpio4 18 gpio3 17 gpio2 16 gnd 15 gpio1 14 www.semtech.com SX8649 ...
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... General Purpose Input/Output 7 Digital Core Decoupling, connect to a 100nF decoupling capacitor Ground Active Low Reset. Connect to VDD if not used. Analog Core Decoupling, connect to a 100nF decoupling capacitor Capacitive Sensor 0 Exposed pad connect to ground Pin description Table 1 © 2010 Semtech Corp. 5 SX8649 DATASHEET www.semtech.com ...
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... ADVANCED COMMUNICATIONS & SENSING 1.4 Simplified Block Diagram The simplified block diagram of the SX8649 is illustrated in Figure 3. Figure 3 1.5 Acronyms ASI Analog Sensor Interface DCV Digital Compensation Value GPI General Purpose Input GPO General Purpose Output GPP General Purpose PWM MTP Multiple Time Programmable ...
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... I2C interface (v) In the event the host processor is reset or undergoes a power OFF/ON cycle recommended that the host also resets the SX8649 and assures that parameters are re-written into the SPM (should these differ to the parameters held in NVM). 2.3 Thermal Characteristics ...
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... VDD and rising INTB type 0402, tolerance +/-50% vdig type 0402, tolerance +/-50% vana type 0402, tolerance +/-10% int type 0402, tolerance +/-50% vdd Electrical Specifications Table 5 © 2010 Semtech Corp. 8 SX8649 DATASHEET Min. Typ. Max. 175 225 80 110 8 17 0.7*VDD VDD + 0.3V V VSS - 0.3V 0.8 ± ...
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... HIGH t SU;DAT t HD;DAT t SU;STA t HD;STA t SU;STO t BUF t SP I2C Timing Specification Table 6 I2C Start and Stop timing Figure 4 I2C Data timing Figure 5 © 2010 Semtech Corp. 9 SX8649 DATASHEET Min. Typ. Max. Unit 400 KHz 1.3 us 0.6 us 100 0.6 us 0.6 us 0.6 us 500 us 50 ...
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... A finger approaching the capacitive sensors will change the charge that can be loaded on the sensors. The SX8649 measures the change of charge and converts that into digital values (ticks). The larger the charge on the sensors, the larger the number of ticks will be. The charge to ticks conversion is done by the SX8649 Analog Sensor Interface (ASI). ...
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... Parameters The SX8649 has many low level built-in, fixed algorithms and procedures. To allow a lot of freedom for the user and adapt the SX8649 for different applications these algorithms and procedures can be configured with a large set of parameters which will be described in the following sections. Examples of parameters are which sensors are buttons or which sensors are parts of a wheel, which GPIO is used for outputs or LEDs and which GPIO is mapped to which button ...
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... In most applications the reaction time needs to be fast when fingers are present, but can be slow when no person uses the application. In case the SX8649 is not used for a specific time it can go from Active mode into Doze mode and power will be saved. This time-out is determined by the Passive Timer which can be configured by the user or turned OFF if not required ...
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... For some applications a single button touch might cause undesired wakening up and Active mode would be entered too often. The SX8649 offers therefore a smart wake-up sequence feature in which the user needs to touch and release a correct sequence of buttons before Active mode will be entered. This is explained in more detail in the Wake-Up Sequence section ...
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... ADVANCED COMMUNICATIONS & SENSING 3.5 Sensors on the PCB The capacitive sensors are relatively simple copper areas on the PCB connected to the eight SX8649 capacitive sensor input pins (CAP0…CAP7).The sensors are covered by isolating overlay material (typically 1mm...3mm). The area of a sensor is typically one square centimeter which corresponds about to the area of a finger touching the overlay material ...
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... The interpolation can be done already on the PCB sensor structures (analog, like the wheel in Figure 10) and as well by SX8649 digital processing of the ticks using center of gravity calculations. The position of the finger on the PCB structures varies between the minimum zero and a user defined maximum (Figure 13) ...
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... CAP7 are the sensors of the wheel then the position ‘zero’ starts at CAP1 and the maximum is found at CAP7. In addition to the wheel position, the SX8649 allows to detect finger rotation. The rotation occurs if the finger position changes a certain step size between two succeeding scan periods. A very slow moving finger will not be considered as a rotation as the changing position will be minor ...
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... The larger the number the cycles are repeated the larger the signal out of the ADC with improved SNR. The sensitivity is therefore directly related to the number of cycles. The SX8649 allows setting the sensitivity for each sensor individually in applications which have a variety of sensors sizes or different overlays or for fine-tuning performances. The optimal sensitivity is depending heavily on the final application ...
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... Once the correct compensation values are found these will be stored and used to compensate each CAP pin. If the SX8649 is shut down the compensation values will be lost next power-up the procedure starts all over again. This assures that the SX8649 will operate under any condition. Powering up at e.g. different temperatures will not change the performance of the SX8649 and the host does not have to do anything special ...
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... The default configuration parameters of the SX8649 are stored in the Quick Start Memory (QSM). This configuration data is setup to a very common application for the SX8649 with buttons and a wheel. Without any programming or host interaction the SX8649 will startup in the Quick Start Application. ...
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... The content of the SPM remains valid as long as the SX8649 is powered and no reset is performed. After a power down or reset the host needs to re-write the SPM if relevant for the application. ...
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... The writing of the host towards the NVM is not done directly but done in 2 steps (Figure 20). In the first step the host writes to the SPM (as in Figure 19). In the second step the host signals the SX8649 to copy the SPM content into the NVM. ...
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... As soon as the INTB rises the SX8649 will be ready for I2C communication. 3.14.2 RESETB When RESETB is driven low the SX8649 will reset and start the power up sequence as soon as RESETB is driven high or pulled high. In case the user does not require a hardware reset control pin then the RESETB pin can be connected to VDD. ...
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... To perform a software reset the host needs to write 0xDE followed by 0x00 at the SoftReset register at address 0xB1. Revision 7_6, February 10 Ultra Low Power, Capacitive Button and Wheel Touch Controller (8 sensors) with Enhanced LED Drivers Software Reset Figure 23 © 2010 Semtech Corp. 23 SX8649 DATASHEET www.semtech.com ...
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... During power up the INTB is kept low. Once the power up sequence is terminated the INTB is released autonomously. The SX8649 is then ready for operation. During the power on period the SX8649 stabilizes the internal regulators, RC clocks and the firmware initializes all registers. During the power up the SX8649 is not accessible and I2C communications are forbidden. ...
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... Example A typical example of the assertion and clearing of the INTB and the I2C communication is shown in Figure 25. When a button is touched the SX8649 will assert the interrupt (1). The host will read the IrqSrc information over the I2C and this clears the interrupt (2). If the finger releases the button the interrupt will be asserted (3). The host reading the IrqSrc information will clear the interrupt (4) ...
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... Ultra Low Power, Capacitive Button and Wheel Touch Controller (8 sensors) with Enhanced LED Drivers GpioMode GpioPullUpDown GpioInterrupt GpioDebounce IrqSrc[4] GpiStat SPM/I2C Parameters Applicable in GPI Mode LED control in GPP mode Figure 28 © 2010 Semtech Corp. 26 SX8649 DATASHEET GPI www.semtech.com ...
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... Ultra Low Power, Capacitive Button and Wheel Touch Controller (8 sensors) with Enhanced LED Drivers GpioMode GpioOutPwrUp GpioPolarity GpioIntensityOn GpioIntensityOff GpioFunction GppPinId GppIntensity SPM/I2C Parameters Applicable in GPP Mode Autolight ON (mapped to Button) © 2010 Semtech Corp. 27 DATASHEET GPP Autolight OFF www.semtech.com SX8649 ...
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... Please note that standard high/low logic signals are just a specific case of GPO mode and can also be generated simply by setting inc/dec time to 0 (ie OFF) and programming intensity OFF/ON to 0x00 and 0xFF. Revision 7_6, February 10 Ultra Low Power, Capacitive Button and Wheel Touch Controller (8 sensors) with Enhanced LED Drivers © 2010 Semtech Corp. 28 SX8649 DATASHEET www.semtech.com ...
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... Ultra Low Power, Capacitive Button and Wheel Touch Controller (8 sensors) with Enhanced LED Drivers GpioMode GpioOutPwrUp GpioAutoligth GpioPolarity GpioIntensityOn GpioIntensityOff GpioFunction GpioIncFactor GpioDecFactor GpioIncTime GpioDecTime GpioOffDelay GpoCtrl SPM/I2C Parameters Applicable in GPO Mode © 2010 Semtech Corp. 29 SX8649 DATASHEET GPO ...
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... Semtech Corp. 30 SX8649 DATASHEET Index Lin/Log Index Lin/Log Index 160 161/81 192 193/125 224 161 162/82 193 194/127 225 162 163/83 194 ...
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... ADVANCED COMMUNICATIONS & SENSING 3.17 Smart Wake Up The SX8649 offers a smart wake up mechanism which allows waking-up from the Doze low power mode to the Active mode in a secure/controlled way and not by any unintentional sensor activation. Until the full correct wake-up sequence is entered, the SX8649 will remain in Doze mode. Any wrong key implies the whole sequence to be entered again ...
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... ADVANCED COMMUNICATIONS & SENSING DESCRIPTIONS 4.1 Introduction This chapter describes briefly the pins of the SX8649, the way the pins are protected, if the pins are analog, digital, require pull up or pull down resistors and show control signals if these are available. 4.2 ASI pins CAP0, CAP1, ..., CAP7 The capacitance sensor pins (CAP0, CAP1, ...
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... Revision 7_6, February 10 Ultra Low Power, Capacitive Button and Wheel Touch Controller (8 sensors) with Enhanced LED Drivers SX8649 VANA CP VANA CN Simplified diagram of CN and CP Figure 36 VDD SX8649 R_INT INTB Simplified diagram of INTB Figure 37 © 2010 Semtech Corp. 33 SX8649 DATASHEET ASI INT www.semtech.com ...
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... Revision 7_6, February 10 Ultra Low Power, Capacitive Button and Wheel Touch Controller (8 sensors) with Enhanced LED Drivers VDD SX8649 SCL Simplified diagram of SCL Figure 38 VDD SX8649 SDA Simplified diagram of SDA Figure 39 © 2010 Semtech Corp. 34 SX8649 DATASHEET SCL_IN SDA_IN SDA_OUT www.semtech.com ...
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... Revision 7_6, February 10 Ultra Low Power, Capacitive Button and Wheel Touch Controller (8 sensors) with Enhanced LED Drivers VDD SX8649 RESETB Simplified diagram of RESETB controlled by host VDD SX8649 RESETB Simplified diagram of RESETB without host control © 2010 Semtech Corp. 35 SX8649 DATASHEET RESETB_IN RESETB_IN www.semtech.com ...
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... VDD has protection to GROUND. Figure 42 shows a simplified diagram of the VDD pin. GND The SX8649 has four ground pins all named GND. These pins and the package center pad need to be connected to ground potential. The GND has protection to VDD. Figure 43 shows a simplified diagram of the GND pin. ...
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... ADVANCED COMMUNICATIONS & SENSING VANA, VDIG The SX8649 has on-chip regulators for internal use (pins VANA and VDIG). VANA and VDIG have protection to VDD and to GND. The output of the regulators needs to be de-coupled with a small 100nF capacitor to ground. Figure 44 shows a simplified diagram of the VANA and VDIG pin. ...
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... C ETAILED ONFIGURATION DESCRIPTIONS 5.1 Introduction The SX8649 configuration parameters are taken from the QSM or the NVM and loaded into the SPM as explained in the chapter ‘functional description’. This chapter describes the details of the configuration parameters of the SX8649. . The SPM is split by functionality into 6 configuration sections: • ...
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... SPM address map: 0x00…0x3F Table 12 © 2010 Semtech Corp. 39 SX8649 DATASHEET Name Reserved BtnCfg BtnAvgThresh BtnCompNegThresh BtnCompNegCntMax BtnHysteresis BtnStuckAtTimeout WhlCfg WhlStuckAtTimeout WhlHysteresis Reserved WhlNormMsb WhlNormLsb WhlAvgThresh WhlCompNegThresh ...
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... SPM address map: 0x40…0x7F Table 13 © 2010 Semtech Corp. 40 SX8649 DATASHEET Name default QSM value GpioDecTime1_0 0x44 GpioOffDelay7_6 0x00 GpioOffDelay5_4 0x00 GpioOffDelay3_2 0x00 GpioOffDelay1_0 0x00 GpioPullUpDown7_4 0x00 ...
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... Doze Mode Scan Period (Figure 7) 0x00: Reserved 0x01: 15ms … 0x0D: 195ms (default) … 0xFF: 255 x 15ms Passive Timer on Button and Wheel Information (Figure 8) 0x00: OFF (default) 0x01: 1 second … 0xFF: 255 seconds General Parameters Table 14 © 2010 Semtech Corp. 41 SX8649 DATASHEET www.semtech.com ...
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... CAP3 Touch Threshold CAP4 Touch Threshold CAP5 Touch Threshold CAP6 Touch Threshold CAP7 Touch Threshold Reserved Reserved Reserved Reserved © 2010 Semtech Corp. 42 SX8649 DATASHEET Reserved: ‘01’ Defines the mode of Default Wheel the CAP pin. Wheel 00: Disabled 01: Button Wheel 10: Reserved ...
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... CAP pin modes Table 16 Possible © 2010 Semtech Corp. 43 SX8649 DATASHEET Defines the periodic offset compensation. 0x0: OFF (default) 0x1: 1 second 0x2: 2 seconds … 0x7: 7 seconds 0x8: 16 seconds 0x9: 18 seconds … 0xE: 28 seconds ...
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... Crossing wheel PCB sensors and CAP number is not allowed. Figure 48 shows a valid configuration and a wrong configuration where CAP5 andCAP6 are not routed correctly on the PCB. Revision 7_6, February 10 Ultra Low Power, Capacitive Button and Wheel Touch Controller (8 sensors) with Enhanced LED Drivers Button examples Figure 46 © 2010 Semtech Corp. 44 SX8649 DATASHEET www.semtech.com ...
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... Revision 7_6, February 10 Ultra Low Power, Capacitive Button and Wheel Touch Controller (8 sensors) with Enhanced LED Drivers Approximate Sensitivity Maximum Tick Level 1000 0 1 2000 2 3000 3 4000 4 5000 5 6000 6 7000 7 8000 ASI Maximum Tick Levels Table 17 © 2010 Semtech Corp. 45 SX8649 DATASHEET www.semtech.com ...
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... CapThresh0, CapThresh1, CapThresh2, CapThresh3, CapThresh4, CapThresh5, CapThresh6, CapThresh7: For each CAP pin a threshold level can be set individually. The threshold levels are used by the SX8649 for making touch and release decisions on e.g. touch or no- touch. The details are explained in the sections for buttons and wheel. ...
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... Defines the button hysteresis corresponding to a percentage of the CAP thresholds (defined in Table 18). 0x00: 0% … 0x0A: 10% (default) … 0x64: 100% All buttons use the same hysteresis Defines the stuck at timeout. 0x00: OFF (default) © 2010 Semtech Corp. 47 SX8649 DATASHEET www.semtech.com ...
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... The release is detected immediately (BtnCfg [3:2] = 00) at the first sample which is below the threshold minus the hysteresis. BtnCfg The SX8649 can report all touches of multiple fingers or the SX8649 can be set to report only the first detected touch. In the later case all succeeding touches are ignored. The very first touch should be released before a next touch will be detected. ...
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... BtnAvgThresh. This mechanism avoids that a valid touch will be averaged and finally the tick difference becomes zero. In case three or more sensors reach the BtnAvgThresh value simultaneously then the SX8649 will start an offset compensation procedure. Small environmental and system noise cause the ticks to vary slowly around the zero idle mode value. ...
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... After the actual finger release the button can be touched again and will be reported as usual. In case the stuckat timer is not required it can be set to zero. Revision 7_6, February 10 Ultra Low Power, Capacitive Button and Wheel Touch Controller (8 sensors) with Enhanced LED Drivers © 2010 Semtech Corp. 50 SX8649 DATASHEET www.semtech.com ...
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... Defines the threshold for detecting a rotate clockwise or counter clockwise. The threshold is a percentage of the maximum wheel position. 0x00: 0% … 0x02: 2% (default) © 2010 Semtech Corp. 51 DATASHEET Defines the 16 bits wheel norm (default 0x0200) www.semtech.com SX8649 ...
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... Hysteresis Touch (touch debounce = 1) WhlHysteresis CapThreshold = scan events @ scan period = no-touch = touch Touch (touch debounce = 1) WhlHysteresis ouch and Release Example Figure 51 T © 2010 Semtech Corp. 52 DATASHEET − CapThresh ( i )) Release (release debounce = 0) time (release debounce = 0) www.semtech.com SX8649 ...
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... Ultra Low Power, Capacitive Button and Wheel Touch Controller (8 sensors) with Enhanced LED Drivers − ∑ ticks _ WhlNorm ∗ − ∑ ticks _ diff = i 0 Wheel Position Figure 52 WhlNorm = × © 2010 Semtech Corp. 53 DATASHEET − diff ) ( i CapThresh ( i )) − CapThresh ( i )) www.semtech.com SX8649 ...
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... Small environmental and system noise cause the ticks to vary slowly around the zero idle mode value. Revision 7_6, February 10 Ultra Low Power, Capacitive Button and Wheel Touch Controller (8 sensors) with Enhanced LED Drivers Wheel Position zero with different offsets © 2010 Semtech Corp. 54 SX8649 DATASHEET www.semtech.com ...
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... In case the stuckat timer is not required it can be set to zero. Revision 7_6, February 10 Ultra Low Power, Capacitive Button and Wheel Touch Controller (8 sensors) with Enhanced LED Drivers Negative Ticks Offset Compensation Trigger the wheel status is touched. hysteresis © 2010 Semtech Corp. 55 SX8649 DATASHEET www.semtech.com ...
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... If any of the enabled sensor events occurs the Group0 event will occur as well. All sensors events within the group can be independently set except wheel event Segment which is exclusive (ie must be the only one enabled to be used) www.semtech.com SX8649 0xC 0xC 0xC 0xC 0x3 0x2 ...
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... This hysteresis applies to all segments of the wheel. Mapping Parameters Table 20 © 2010 Semtech Corp. 57 DATASHEET Defines Group1 sensor events: 0: OFF (default any of the enabled sensor events occurs the Group0 event will occur as well. All sensors events within the group can be independently set. www.semtech.com SX8649 ...
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... Touch Rotation Clock Wise Rotation Clock Counter Wise or Release Rotation Counter Clock Wise Segment Touched Autolight Mapping, Sensor Information © 2010 Semtech Corp. 58 SX8649 DATASHEET and the sensor information which GPO OFF Release Release Rotation Clock Wise or Release Segment Released www.semtech.com ...
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... GPIO[4] Output Polarity GPIO[3] Output Polarity GPIO[2] Output Polarity GPIO[1] Output Polarity GPIO[0] Output Polarity 7:0 ON Intensity Index © 2010 Semtech Corp. 59 SX8649 DATASHEET Defines the GPIO mode. 00: GPO (default) 01: GPP 10: GPI 11: Reserved Defines the values of GPO and GPP pins after power up ie default values of I2C parameters GpoCtrl and GppIntensity respectively ...
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... GPIO[4] Fading Decrement Factor GPIO[3] Fading Decrement Factor GPIO[2] Fading Decrement Factor GPIO[1] Fading Decrement Factor GPIO[0] Fading Decrement Factor 7:4 GPIO[7] Fading Increment Time © 2010 Semtech Corp. 60 SX8649 DATASHEET … 0xFF: 255 (default) Defines the OFF intensity index 0x00: 0 (default) 0x01: 1 … ...
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... GPIO[0] Pullup/down 7:6 GPI[7] Interrupt 5:4 GPI[6] Interrupt 3:2 GPI[5] Interrupt 1:0 GPI[4] Interrupt 7:6 GPI[3] Interrupt 5:4 GPI[2] Interrupt 3:2 GPI[1] Interrupt © 2010 Semtech Corp. 61 SX8649 DATASHEET 0x0: OFF (default) 0x1: 0.5ms 0x2: 1ms … 0xF: 7.5ms The total fading in time will be: GpioIncTime*GpioIncFactor* (GpioIntensityOn – GpioIntensityOff) Defines the fading decrement time ...
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... GPI[2] Debounce GPI[1] Debounce GPI[0] Debounce GPIO Parameters Table 22 GPI Applicable SPM/I2C Parameters vs. GPIO Mode © 2010 Semtech Corp. 62 SX8649 DATASHEET Enables the GPI debounce (done on 10 consecutive samples at 1ms OFF (default GPP GPO ...
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... After the start condition [S], the slave address (SA) is sent, followed by an eighth bit (‘0’) indicating a Write. The SX8649 then Acknowledges [A] that it is being addressed, and the Master sends an 8 bit Data Byte consisting of the SX8649 Register Address (RA). The Slave Acknowledges [A] and the master sends the appropriate 8 bit Data Byte (WD0) ...
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... The SX8649 responds with an Acknowledge [A] and the read Data byte (RD0). If the master needs to read more data it will acknowledge [A] and the SX8649 will send the next read byte (RD1). This sequence can be repeated until the master terminates with a NACK [N] followed by a stop [P]. ...
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... Reserved SpmKeyMsb read/write SpmkeyLsb read/write SoftReset read/write I2C Registers Overview Table 24 © 2010 Semtech Corp. 65 SX8649 DATASHEET Description Interrupt Source Wheel/Button Status MSB Button Status LSB Wheel Position MSB Wheel Position LSB GPI Status SPM Status Compensation and Operating Mode ...
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... Buttons interrupt flag 1 Compensation interrupt flag 0 Operating Mode interrupt flag Interrupt Source Table 25 © 2010 Semtech Corp. 66 SX8649 DATASHEET Interrupt source flags 0: Inactive (default) 1: Active INTB goes low if any of these bits is set. More than one bit can be set. Reading IrqSrc clears it together with INTB ...
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... Shows the current (touched) or last (released) wheel position[15:0] unsigned (default 0x00) Wheel Position[7:0] Wheel position MSB/LSB Table 27 Description Status of each individual GPI pin 0: Low GPI[7:0] 1: High Status Bits of non-GPI pins are set to 0. I2C GPI status Table 28 © 2010 Semtech Corp. 67 SX8649 DATASHEET www.semtech.com ...
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... Once – NVM is used if NvmValid = 1, else QSM. NvmCount 2: Twice – NVM is used if NvmValid = 1, else QSM. 3: Three times – NVM is used if NvmValid = 1, else QSM. 4: More than three times – QSM is used I2C SPM status Table 29 © 2010 Semtech Corp. 68 SX8649 DATASHEET www.semtech.com ...
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... I2C compensation, operation modes Bits Description Triggers ON/OFF state of GPOs when Autolight is OFF 0: OFF ( IntensityOff) 7:0 GpoCtrl[7: ( IntensityOn) Default is set by SPM parameter GpioOutPwrUp Bits of non-GPO pins are ignored. I2C GPO Control Table 31 © 2010 Semtech Corp. 69 SX8649 DATASHEET www.semtech.com ...
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... Reading returns the intensity index of the GPP pin selected in GppPinId. Default value is IntensityOn or IntensityOff depending on GpioOutPwrUp. I2C GPP Intensity Table 33 Description Writing 0xDE followed by 0x00 will reset the chip. Soft Reset Table 34 I2C © 2010 Semtech Corp. 70 SX8649 DATASHEET www.semtech.com ...
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... ADVANCED COMMUNICATIONS & SENSING 6.6 SPM Gateway Registers The SX8649 I2C interface offers two registers for exchanging the SPM data with the host. • SpmCfg • SpmBaseAddr Address Name 0x0D SpmCfg Address Name 0x0E SpmBaseAddr The exchange of data, read and write, between the host and the SPM is always done in bursts of eight bytes. ...
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... IrqSrc[5] set. In Sleep mode the SPM write can be actually applied with a delay of 30ms. The host clears the interrupt and IrqSrc[5] by reading the IrqSrc register. Revision 7_6, February 10 Ultra Low Power, Capacitive Button and Wheel Touch Controller (8 sensors) with Enhanced LED Drivers Figure 57: SPM Write Sequence © 2010 Semtech Corp. 72 SX8649 DATASHEET www.semtech.com ...
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... The complete SPM can be read by repeating 16 times the cycles shown in Figure 58 using base addresses 0x00, 0x08, 0x10, …, 0x70, 0x78. Revision 7_6, February 10 Ultra Low Power, Capacitive Button and Wheel Touch Controller (8 sensors) with Enhanced LED Drivers Figure 58: SPM Read Sequence © 2010 Semtech Corp. 73 SX8649 DATASHEET www.semtech.com ...
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... Figure 59 shows the simplified diagram of the NVM counter. The SX8649 is delivered with empty NVM and NvmCount set to zero. The SPM points to the QSM. Each NVM burn will increase the NvmCount. At the fourth NVM burn the SX8649 switches definitely to the QSM. The burning of the SPM into the NVM is done by executing a special sequence of four I2C commands. ...
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... ADVANCED COMMUNICATIONS & SENSING PPLICATION NFORMATION A typical application schematic is shown in Figure 61. Revision 7_6, February 10 Ultra Low Power, Capacitive Button and Wheel Touch Controller (8 sensors) with Enhanced LED Drivers Typical Application Figure 61 © 2010 Semtech Corp. 75 SX8649 DATASHEET www.semtech.com ...
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... P I ACKAGING NFORMATION 8.1 Package Outline Drawing SX8649 is assembled in a MLPQ-UT28 package as shown in Figure 62. 8.2 Land Pattern The land pattern of MLPQ-UT28 package shown in Figure 63. Revision 7_6, February 10 Ultra Low Power, Capacitive Button and Wheel Touch Controller (8 sensors) with Enhanced LED Drivers ...
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... Advanced Communications and Sensing Products Division 200 Flynn Road, Camarillo, CA 93012 Phone: (805) 498-2111 Fax: (805) 498-3804 Revision 7_6, February 10 Ultra Low Power, Capacitive Button and Wheel Touch Controller (8 sensors) with Enhanced LED Drivers © 2010 Semtech Corp. 77 SX8649 DATASHEET www.semtech.com ...