IQS228AS-00000000 TSR

IQ Switch Azoteq ProxSense Series IQS228AS/B DATASHEET Single channel capacitive proximity and touch controller The ProxSense IQS228AS/B is a single channel self-capacitive sensor with Dynamic Calibration (DYCAL) to allow for sensor drift during prolonged activation. Features > 1 Self capacitive channel > DYCAL: Intelligent Hysteresis > Proximity and Touch outputs > Automatic Tuning > Internal Reference Capacitor > Minimum external components > 1-Wire data streaming RoHS2 2 > I C Debug option Compliant > User selectable options (OTP): > Ext sync control or Ext filter control > I/O Sink or Source selection > Time-out for stuck key > Proximity and Touch sensitivity selections > Low Power modes > Low power mode 2.5A > Supply voltage: 1.8V to 3.6V Applications > Proximity sensors > SAR detection for Tablets > On-ear detection for mobile phones > 3D glasses > Personal Media Players > White goods and appliances > Human Interface Devices > Proximity activated backlighting Available Options T TSOT23-6 WLCSP-8 DFN-6 A -20C to 85C IQS228AS - - -40C to 85C IQS228B IQS228B IQS228B Copyright Azoteq (Pty) Ltd 2021 IQS228AS/B Datasheet Page 1 of 41 All rights reserved Revision 1.40 November 2021 IQ Switch Azoteq ProxSense Series Contents IQS228AS/B DATASHEET ..................................................................................................................................................... 1 1 OVERVIEW ........................................................................................................................................................................ 5 1.1 DEVICE ...................................................................................................................................................... 5 1.2 OPERATION ................................................................................................................................................ 5 1.3 APPLICABILITY ............................................................................................................................................ 5 2 PACKAGING AND PIN-OUT ............................................................................................................................................... 6 2.1 IQS228AS/B ............................................................................................................................................. 6 2.1.1 Pin-out TSOT23-6 ............................................................................................................................. 6 2.1.2 Pin-out WLCSP-8 .............................................................................................................................. 7 2.1.3 Pin-out DFN-6 .................................................................................................................................... 8 2.2 SCHEMATIC ................................................................................................................................................ 9 2.2.1 TSOT23-6 .......................................................................................................................................... 9 2.2.2 WLCSP-8 .........................................................................................................................................10 2.2.3 DFN-6 ..............................................................................................................................................11 3 USER CONFIGURABLE OPTIONS ..................................................................................................................................... 12 3.1 CONFIGURING DEVICES ............................................................................................................................ 12 3.1.1 IQS228AS/B User Selectable Options ............................................................................................12 4 MEASURING CAPACITANCE USING THE CHARGE TRANSFER METHOD .......................................................................... 15 5 DYCAL OPERATION ...................................................................................................................................................... 16 6 OPERATING PRINCIPLE ................................................................................................................................................... 17 7 CONFIGURABLE SETTINGS .............................................................................................................................................. 17 7.1 CTRL: EXTERNAL CONTROL ..................................................................................................................... 17 7.1.1 Charge Halt ......................................................................................................................................17 7.1.2 Halt LTA Filter ..................................................................................................................................17 7.1.3 Pulse on CTRL: ...............................................................................................................................17 7.2 LOGIC .................................................................................................................................................... 18 7.3 RF NOISE ON IQS228AS/B ...................................................................................................................... 18 7.3.1 ND: RF Noise Detection ..................................................................................................................18 7.3.2 IQS228AS/B RF Noise Immunity.....................................................................................................18 7.4 PROXIMITY THRESHOLD ............................................................................................................................ 19 7.5 TOUCH THRESHOLD ................................................................................................................................. 19 7.6 MULTIPLIERS ............................................................................................................................................ 19 7.7 CHARGE TRANSFER ................................................................................................................................. 19 7.8 TARGET COUNTS ..................................................................................................................................... 19 7.9 ENABLE PARTIAL ATI................................................................................................................................ 19 7.10 DYCAL TURBO .................................................................................................................................... 20 7.11 FILTER HALT .......................................................................................................................................... 20 7.12 LOW POWER MODES .............................................................................................................................. 20 7.13 ZOOM .................................................................................................................................................... 20 8 STREAMING MODE ......................................................................................................................................................... 21 8.1 EVENT MODE ........................................................................................................................................... 22 2 8.2 I C .......................................................................................................................................................... 22 9 AUTO TUNING IMPLEMENTATION (ATI) ......................................................................................................................... 23 9.1 FULL ATI ................................................................................................................................................. 23 9.2 ATI TARGET ............................................................................................................................................. 23 9.3 ATIBASE: SIGNIFICANCE OF ATI BASE ........................................................................................................ 23 Copyright Azoteq (Pty) Ltd 2021 IQS228AS/B Datasheet Page 2 of 41 All rights reserved Revision 1.40 November 2021