SX8636I05AULTRT1 SEMTECH [Semtech Corporation], SX8636I05AULTRT1 Datasheet
SX8636I05AULTRT1
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SX8636I05AULTRT1 Summary of contents
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ADVANCED COMMUNICATIONS & SENSING G D ENERAL ESCRIPTION The SX8636 is an ultra low power, fully integrated 8- channel solution for capacitive touch-buttons and proximity detection applications. capacitive touch solutions, the SX8636 features dedicated capacitive sense inputs (that requires no ...
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ADVANCED COMMUNICATIONS & SENSING G D ........................................................................................................................ 1 ENERAL ESCRIPTION T A YPICAL PPLICATION CIRCUIT ..................................................................................................................... 1 EY RODUCT EATURES A ....................................................................................................................................... 1 PPLICATIONS O I ...................................................................................................................... 1 RDERING NFORMATION ENERAL ESCRIPTION 1.1 Pin ...
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ADVANCED COMMUNICATIONS & SENSING 3.16 General Purpose Input and Outputs 3.16.1 Introduction and Definitions 3.16.2 GPI 3.16.3 GPP 3.16.4 GPO 3.16.5 Intensity index vs PWM pulse width 3.17 Smart Wake ....................................................................................................................... 3 IN DESCRIPTIONS 4.1 Introduction 4.2 ...
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ADVANCED COMMUNICATIONS & SENSING ENERAL ESCRIPTION 1.1 Pin Diagram 1.2 Marking information Revision 7_5, September 10 Low Power, Capacitive Button Touch Controller (8 sensors) with Enhanced LED Drivers and Proximity Sensing ...
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ADVANCED COMMUNICATIONS & SENSING 1.3 Pin Description Number Name Type 1 CAP1 Analog 2 CAP2 Analog 3 CAP3 Analog 4 CAP4 Analog 5 CAP5 Analog 6 CAP6 Analog 7 CAP7 Analog 8 CN Analog 9 CP Analog 10 VDD Power ...
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ADVANCED COMMUNICATIONS & SENSING 1.4 Simplified Block Diagram The simplified block diagram of the SX8636 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 ...
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ADVANCED COMMUNICATIONS & SENSING LECTRICAL HARACTERISTICS 2.1 Absolute Maximum Ratings Stresses above the values listed in “Absolute Maximum Ratings” may cause permanent damage to the device. This is a stress rating only and functional operation of the ...
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ADVANCED COMMUNICATIONS & SENSING 2.4 Electrical Specifications All values are valid within the operating conditions unless otherwise specified. Parameter Symbol Current consumption Active mode, average I OP,active Doze mode, average I OP,Doze Sleep I OP,sleep GPIO, set as Input, RESETB, ...
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ADVANCED COMMUNICATIONS & SENSING Parameter (i) I2C Timing Specifications SCL clock frequency SCL low period SCL high period Data setup time Data hold time Repeated start setup time Start condition hold time Stop condition setup time Bus free time between ...
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ADVANCED COMMUNICATIONS & SENSING 3 F UNCTIONAL DESCRIPTION 3.1 Quickstart Application The SX8636 is preconfigured (Quickstart Application) for an application with eight buttons and eight LED drivers using logarithmic PWM fading. Implementing a schematic based on Figure 6 will be ...
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ADVANCED COMMUNICATIONS & SENSING 3.2.2 GPIOs A second path of feedback to the user is using General Purpose Input Output (GPIO) pins. The SX8636 offers eight individual configurable GPIO pins. The GPIO can e.g. be set as a LED driver ...
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ADVANCED COMMUNICATIONS & SENSING 3.3 Scan Period The basic operation Scan period of the SX8636 sensing interface can be split into three periods over time. In the first period (Sensing) the SX8636 is sensing all enabled CAP inputs, from CAP0 ...
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ADVANCED COMMUNICATIONS & SENSING To leave Doze mode and enter Active mode this can be done by a simple touch on any button. For some applications a single button touch might cause undesired wakening up and Active mode would be ...
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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 SX8636 capacitive sensor input pins (CAP0…CAP7).The sensors are covered by isolating overlay material (typically 1mm...3mm). The ...
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ADVANCED COMMUNICATIONS & SENSING 3.7 Analog Sensing Interface The Analog Sensing Interface (ASI) converts the charge on the sensors into ticks which will be further digitally processed. The basic principle of the ASI will be explained in this section. The ...
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ADVANCED COMMUNICATIONS & SENSING The ticks from the ASI will then be handled by the digital processing. 3.8 Offset Compensation The capacitance at the CAP pins is determined by an intrinsic capacitance of the integrated circuit, the PCB traces, ground ...
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ADVANCED COMMUNICATIONS & SENSING 3.9 Processing The first processing step of the raw ticks, coming out of the ASI, is low pass filtering to obtain an estimation of the average capacitance: tick-ave (see Figure 12). This slowly varying average is ...
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ADVANCED COMMUNICATIONS & SENSING The QSM settings are fixed and can not be changed by the user. In case the application needs different settings than the QSM settings then the SX8636 can be setup and/or programmed over the I2C interface. ...
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ADVANCED COMMUNICATIONS & SENSING The writing of the host towards the NVM is not done directly but done in 2 steps (Figure 15). In the first step the host writes to the SPM (as in Figure 14). In the second ...
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ADVANCED COMMUNICATIONS & SENSING 3.14 Reset The reset can be performed by 3 sources: - power up, - RESETB pin, - software reset. 3.14.1 Power up During power up the INTB is kept low. Once the power up sequence is ...
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ADVANCED COMMUNICATIONS & SENSING 3.14.3 Software Reset To perform a software reset the host needs to write 0xDE followed by 0x00 at the SoftReset register at address 0xB1. Revision 7_5, September 10 Low Power, Capacitive Button Touch Controller (8 sensors) ...
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ADVANCED COMMUNICATIONS & SENSING 3.15 Interrupt 3.15.1 Power up During power up the INTB is kept low. Once the power up sequence is terminated the INTB is released autonomously. The SX8636 is then ready for operation. During the power on ...
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ADVANCED COMMUNICATIONS & SENSING 3.15.4 Example A typical example of the assertion and clearing of the INTB and the I2C communication is shown in Figure 20. When a button is touched the SX8636 will assert the interrupt (1). The host ...
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ADVANCED COMMUNICATIONS & SENSING The PWM blocks used in GPP and GPO modes are 8-bits based and clocked at 2MHz typ. hence offering 256 selectable pulse width values with a granularity of 128us typ. Figure 22 PWM definition, (a) small ...
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ADVANCED COMMUNICATIONS & SENSING SPM I2C 1 At power up, GppIntensity of each GPP pin is initialized with GpioIntensityOn or GpioIntensityOff depending on GpioOutPwrUp corresponding bits value. Table 8 3.16.4 GPO GPIOs configured as GPO will operate as digital outputs ...
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ADVANCED COMMUNICATIONS & SENSING GPO ON transition (LED fade in), inverted polarity, (a) linear, (b) logarithmic Figure 27 The fading out (e.g. after a button is released) is identical to the fading in but an additional off delay can be ...
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ADVANCED COMMUNICATIONS & SENSING SPM/I2C parameters applicable in GPO mode are listed in table below. SPM I2C 1 Only if Autolight is OFF, else must be left to 0 (default value) 2 Only if Autolight is OFF, else ignored Table ...
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ADVANCED COMMUNICATIONS & SENSING 3.16.5 Intensity index vs PWM pulse width Tables below are used to convert all intensity indexes parameters GpioIntensityOff, GpioIntensityOn and GppIntensity but also to generate fading in GPO mode During fading in(out), the index is automatically ...
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ADVANCED COMMUNICATIONS & SENSING 3.17 Smart Wake Up The SX8636 offers a smart wake up mechanism ( keys) which allows waking-up from the Doze low power mode to the Active mode in a secure/controlled way and not by ...
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ADVANCED COMMUNICATIONS & SENSING DESCRIPTIONS 4.1 Introduction This chapter describes briefly the pins of the SX8636, the way the pins are protected, if the pins are analog, digital, require pull up or pull down resistors and show ...
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ADVANCED COMMUNICATIONS & SENSING 4.3 Host interface pins The host interface consists of the interrupt pin INTB, a reset pin RESETB and the standard I2C pins: SCL and SDA. INTB The INTB pin is an open drain output that requires ...
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ADVANCED COMMUNICATIONS & SENSING SCL The SCL pin is a high impedance input pin. The SCL pin is protected to VDD, using dedicated devices, in order to conform to standard I2C slave specifications. The SCL pin has diode protected to ...
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ADVANCED COMMUNICATIONS & SENSING RESETB The RESETB pin is a high impedance input pin. The RESETB pin is protected to VDD using dedicated devices. The RESETB pin has diode protected to GROUND. Figure 35 shows the simplified diagram of the ...
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ADVANCED COMMUNICATIONS & SENSING 4.4 Power management pins The power management pins consist of the Power, Ground and Regulator pins. VDD VDD is a power pin and is the main power supply for the SX8636. VDD has protection to GROUND. ...
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ADVANCED COMMUNICATIONS & SENSING VANA, VDIG The SX8636 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 ...
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ADVANCED COMMUNICATIONS & SENSING ETAILED ONFIGURATION DESCRIPTIONS 5.1 Introduction The SX8636 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 ...
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ADVANCED COMMUNICATIONS & SENSING Address Name 0x00 Reserved 0x01 Reserved 0x02 Reserved 0x03 Reserved 0x04 I2CAddress 0x05 ActiveScanPeriod DozeScanPeriod 0x06 0x07 PassiveTimer 0x08 Reserved CapModeMisc 0x09 0x0A Reserved 0x0B CapMode7_4 CapMode3_0 0x0C 0x0D CapSensitivity0_1 CapSensitivity2_3 0x0E 0x0F CapSensitivity4_5 0x10 CapSensitivity6_7 ...
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ADVANCED COMMUNICATIONS & SENSING Address Name 0x40 GpioMode7_4 0x41 GpioMode3_0 GpioOutPwrUp 0x42 0x43 GpioAutoLight 0x44 GpioPolarity GpioIntensityOn0 0x45 0x46 GpioIntensityOn1 0x47 GpioIntensityOn2 GpioIntensityOn3 0x48 0x49 GpioIntensityOn4 GpioIntensityOn5 0x4A 0x4B GpioIntensityOn6 0x4C GpioIntensityOn7 GpioIntensityOff0 0x4D 0x4E GpioIntensityOff1 0x4F GpioIntensityOff2 GpioIntensityOff3 0x50 ...
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ADVANCED COMMUNICATIONS & SENSING 5.2 General Parameters General Parameters Address Name Bits 0x04 I2CAddress 7 6:0 0x05 ActiveScanPeriod 7:0 0x06 DozeScanPeriod 7:0 0x07 PassiveTimer 7:0 Revision 7_5, September 10 Low Power, Capacitive Button Touch Controller (8 sensors) with Enhanced LED ...
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ADVANCED COMMUNICATIONS & SENSING 5.3 Capacitive Sensors Parameters Capacitive Sensors Parameters Address Name Bits 0x09 CapModeMisc 7:3 2:0 0x0A Reserved 7:0 0x0B CapMode7_4 7:6 5:4 3:2 1:0 0x0C CapMode3_0 7:6 5:4 3:2 1:0 0x0D CapSensitivity0_1 7:4 3:0 0x0E CapSensitivity2_3 7:4 ...
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ADVANCED COMMUNICATIONS & SENSING Capacitive Sensors Parameters Address Name Bits 0x1F CapPerComp 7:4 3:0 0x70 CapProxEnable 7:0 CapModeMisc By default the ASI is using a common sensitivity for all capacitive sensors as in the usual case overlay material and sensors ...
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ADVANCED COMMUNICATIONS & SENSING CapSensitivity0_1, CapSensitivity2_3, CapSensitivity4_5, CapSensitivity6_7, CapProxEnable: The sensitivity of the sensors can be set between 8 values. The higher the sensitivity is set the larger the value of the ticks will be. The minimum sensitivity can be ...
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ADVANCED COMMUNICATIONS & SENSING 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 SX8636 for making touch and release decisions on e.g. touch ...
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ADVANCED COMMUNICATIONS & SENSING 5.4 Button Parameters Button Parameters Address Name Bits 0x21 BtnCfg 7:6 5:4 3:2 1:0 0x22 BtnAvgThresh 7:0 0x23 BtnCompNegThresh 7:0 0x24 BtnCompNegCntMax 7:0 0x25 BtnHysteresis 7:0 0x26 BtnStuckAtTimeout 7:0 Revision 7_5, September 10 Low Power, Capacitive ...
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ADVANCED COMMUNICATIONS & SENSING Button Parameters Address Name Bits Please note that proximity sensors are configured as buttons and operate exactly the same way as touch buttons. All the parameters and procedures described below apply similarly. A reliable button operation ...
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ADVANCED COMMUNICATIONS & SENSING In case the ticks get slightly positive this is considered as normal operation. Very large positive tick values indicate a valid touch. The averaging filter is disabled as soon as the average reaches the value defined ...
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ADVANCED COMMUNICATIONS & SENSING If the stuckat timer is set to one second then the touch of a finger will last only for one second and then a compensation will be performed and button hence considered released, even if the ...
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ADVANCED COMMUNICATIONS & SENSING 5.5 Mapping Parameters Mapping Parameters Address Name 0x33 MapWakeupSize 0x34 MapWakeupValue0 0x35 MapWakeupValue1 0x36 MapWakeupValue2 0x37 MapAutoLight0 0x38 MapAutoLight1 0x39 MapAutoLight2 0x3A MapAutoLight3 0x3B MapAutoLightGrp0Msb 0x3C MapAutoLightGrp0Lsb 0x3D MapAutoLightGrp1Msb 0x3E MapAutoLightGrp1Lsb Revision 7_5, September 10 Low ...
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ADVANCED COMMUNICATIONS & SENSING Mapping Parameters Address Name MapWakeupSize The number of keys defining the wakeup sequence can be set from the size is set to 0 then wakeup is done on any sensor event. if ...
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ADVANCED COMMUNICATIONS & SENSING 5.6 GPIO Parameters GPIO Parameters Address Name 0x40 GpioMode7_4 0x41 GpioMode3_0 0x42 GpioOutPwrUp 0x43 GpioAutoLight 0x44 GpioPolarity 0x45 GpioIntensityOn0 0x46 GpioIntensityOn1 0x47 GpioIntensityOn2 Revision 7_5, September 10 Low Power, Capacitive Button Touch Controller (8 sensors) with ...
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ADVANCED COMMUNICATIONS & SENSING GPIO Parameters Address Name 0x48 GpioIntensityOn3 0x49 GpioIntensityOn4 0x4A GpioIntensityOn5 0x4B GpioIntensityOn6 0x4C GpioIntensityOn7 0x4D GpioIntensityOff0 0x4E GpioIntensityOff1 0x4F GpioIntensityOff2 0x50 GpioIntensityOff3 0x51 GpioIntensityOff4 0x52 GpioIntensityOff5 0x53 GpioIntensityOff6 0x54 GpioIntensityOff7 0x56 GpioFunction 0x57 GpioIncFactor 0x58 GpioDecFactor ...
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ADVANCED COMMUNICATIONS & SENSING GPIO Parameters Address Name 0x5A GpioIncTime5_4 0x5B GpioIncTime3_2 0x5C GpioIncTime1_0 0x5D GpioDecTime7_6 0x5E GpioDecTime5_4 0x5F GpioDecTime3_2 0x60 GpioDecTime1_0 0x61 GpioOffDelay7_6 0x62 GpioOffDelay5_4 0x63 GpioOffDelay3_2 0x64 GpioOffDelay1_0 0x65 GpioPullUpDown7_4 0x66 GpioPullUpDown3_0 0x67 GpioInterrupt7_4 0x68 GpioInterrupt3_0 Revision 7_5, ...
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ADVANCED COMMUNICATIONS & SENSING GPIO Parameters Address Name 0x69 GpioDebounce Table 22 resumes the applicable SPM and I2C parameters for each GPIO mode. GpioMode GpioOutPwrUp GpioAutoligth GpioPolarity GpioIntensityOn GpioIntensityOff GpioFunction GpioIncFactor SPM GpioDecFactor GpioIncTime GpioDecTime GpioOffDelay GpioPullUpDown GpioInterrupt GpioDebounce IrqSrc[4] ...
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ADVANCED COMMUNICATIONS & SENSING 6 I2C I NTERFACE The I2C implemented on the SX8636 is compliant with: - standard (100kb/s), fast mode (400kb/s) - slave mode - 7 bit address (default 0x2B). The default address can be changed in the ...
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ADVANCED COMMUNICATIONS & SENSING 6.2 I2C read The format of the I2C read is given in Figure 45. After the start condition [S], the slave address (SA) is sent, followed by an eighth bit (‘0’) indicating a Write. The SX8636 ...
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ADVANCED COMMUNICATIONS & SENSING 6.3 I2C Registers Overview Address 0x00 0x01 0x02 0x03 0x04 0x05 0x06 0x07 0x08 0x09 0x0A 0x0B 0x0C 0x0D 0x0E 0x0F 0xAC 0xAD 0xB1 Revision 7_5, September 10 Low Power, Capacitive Button Touch Controller (8 sensors) ...
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ADVANCED COMMUNICATIONS & SENSING 6.4 Status Registers Address Name 0x00 IrqSrc The delay between the actual event and the flags indicating the interrupt source may be one scan period. IrqSrc[6] is set once NVM burn procedure is completed. IrqSrc[5] is ...
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ADVANCED COMMUNICATIONS & SENSING Address Name Bits 0x02 CapStatLsb Address Name Bits 0x07 GpiStat 7:0 Address Name Bits 7:4 3 0x08 SpmStat 2:0 Revision 7_5, September 10 Low Power, Capacitive Button Touch ...
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ADVANCED COMMUNICATIONS & SENSING 6.5 Control Registers Address Name 0x09 CompOpMode Table 28 * The reading of these reserved bits will return varying values. ** After the operating mode change (Active/Doze) the host should wait for INTB or 300ms before ...
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ADVANCED COMMUNICATIONS & SENSING Address Name Bits 7:3 0x0B GppPinId 2:0 Address Name Bits 0x0C GppIntensity 7:0 Address Name Bits 0xB1 SoftReset 7:0 Revision 7_5, September 10 Low Power, Capacitive Button Touch Controller (8 sensors) with Enhanced LED Drivers and ...
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ADVANCED COMMUNICATIONS & SENSING 6.6 SPM Gateway Registers The SX8636 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 ...
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ADVANCED COMMUNICATIONS & SENSING 6.6.1 SPM Write Sequence The SPM write can be done in any mode (Active, Doze, Sleep). Writing the SPM in Sleep is useful to avoid potential transient behaviors. The SPM must always be written in blocks ...
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ADVANCED COMMUNICATIONS & SENSING 6.6.2 SPM Read Sequence The SPM read can be done in any mode (Active, Doze, Sleep). The SPM must always be read in blocks of 8 bytes. The sequence is described below: 1. Set the I2C ...
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ADVANCED COMMUNICATIONS & SENSING 6.7 NVM burn The content of the SPM can be copied permanently (burned) into the NVM to be used as the new default parameters. The burning of the NVM can be done up to three times ...
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ADVANCED COMMUNICATIONS & SENSING PPLICATION NFORMATION 7.1 Typical Application Schematic . Revision 7_5, September 10 Low Power, Capacitive Button Touch Controller (8 sensors) with Enhanced LED Drivers and Proximity Sensing Typical Application Figure 50 © 2010 Semtech ...
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ADVANCED COMMUNICATIONS & SENSING 7.2 Example of Touch+Proximity Module 7.2.1 Overview To demonstrate the proximity sensing feature of the SX863x family, a module has been designed and is illustrated in figure below. The touch button controller is running in stand-alone ...
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ADVANCED COMMUNICATIONS & SENSING - CapSensitivity = 7 (Max) - CapThreshold = 300 - Board main supplied and placed vertically ie same orientation as hand/finger - Finger pointing center button The results obtained are provided in table below: Finger (natural ...
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ADVANCED COMMUNICATIONS & SENSING 7.2.5 Layout Figure 54 Touch+Proximity Figure 55 Touch+Proximity Figure 56 Touch+Proximity Figure 57 Touch+Proximity Revision 7_5, September 10 Low Power, Capacitive Button Touch Controller (8 sensors) with Enhanced LED Drivers and Proximity Sensing Module Layout - ...
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ADVANCED COMMUNICATIONS & SENSING 8 R EFERENCES [1] Capacitive Touch Sensing Layout guidelines on www.semtech.com Revision 7_5, September 10 Low Power, Capacitive Button Touch Controller (8 sensors) with Enhanced LED Drivers and Proximity Sensing © 2010 Semtech Corp. 69 SX8636 ...
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ADVANCED COMMUNICATIONS & SENSING ACKAGING NFORMATION 9.1 Package Outline Drawing SX8636 is assembled in a MLPQ-UT28 package as shown in Figure 58. 9.2 Land Pattern The land pattern of MLPQ-UT28 package ...
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ADVANCED COMMUNICATIONS & SENSING © Semtech 2010 All rights reserved. Reproduction in whole or in part is prohibited without the prior written consent of the copyright owner. The information presented in this document does not form part of any quotation ...