IQ Switch ProxSense Series Azoteq IQS231A/B DATASHEET Single Channel Capacitive Proximity/Touch Controller for SAR Applications 1 Device Overview The IQS231A/B ProxSense IC is a self-capacitance controller designed for applications where an awake/activate on proximity function is required. The IQS231A/B is an ultra-low power solution that uses unique release and/or movement detection for applications that require long- term detection. 2 The IQS231A/B operates standalone or I C and features configuration via OTP (One Time 2 Programmable) bits. Switching from I C to standalone during runtime is also possible in order to access all settings while offering the simplicity of a standalone output. IQS231B offers alternate hardware with identical firmware to the IQS231A. IQS231B hardware offers improved temperature response and low temperature range. 1.1 Main Features > Integrated SAR user interface offering a > Extended controls in I2C mode (setup in I2C, simple GPIO output runtime with standalone output) > Quick release detection effectively > Optional input for synchronized prevent false triggers from remaining implementations (input to instruct IC when to sense) > Quick release sensitivity options 6 pin TSOT23-6 RoHS2 > Wide range of control for sensing in high Compliant power RF environments 8 pin WLCSP-8 6 pin DFN6 > Pin compatible with devices of same package type (All ProxSense TSOT23-6 devices1,IQS211A WLCSP-8 device) > 1.8V (-2%) to 3.6V Input voltage Representations only, not actual markings > Capacitive resolution down to 0.02fF > Capacitive load capability up to 120pF > Synchronization output failsafe pulses may > External threshold adjustment pin be used by the master to synchronize on. (minimize need for pre-empted OTP Sensing is done after each pulse adjustments) > Synchronization input Sensing is only done > Minimal external components (direct while Sync input is low input strap) > Low power sensing: 30Hz (default), 100Hz, > Standalone failsafe mode (backwards 8Hz, 4Hz (sub 6uA mode) compatible failsafe output, short pulses > Constant sampling rates during all power on output to indicate operational device) modes with rapidly debounced output > Default OTP options focus on safety and changes passing SAR lab qualification, OTP > Advanced temperature & interference changes offer performance advantages compensation option > I2C interface option (improved compatibility) 1 Input voltage level and pin functions may differ Copyright Azoteq (Pty) Ltd 2020 IQS231A/B Datasheet Page 1 of 47 All Rights Reserved Revision 2.5 October 2021 IQ Switch ProxSense Series Azoteq 1.2 Applications > SAR sensor > Hold detection for screen activation > Integrated hybrid designs (RF and > On-ear detection capacitive sensing combined) > Movement sensing applications (user interaction detection, anti-theft) T DFN6 TSOT23-6 WLCSP-8 (1.5 x 0.9 x 0.4mm) A -20C to 85 C IQS231A IQS231A (NRFND) -40C to 85 C IQS231B IQS231B IQS231B 1.3 Block Diagram VDDHI VDDHI VREG BOD Non- Internal POR Digital - P, RAM, ROM volatile regulator circuit memory VSS SDA / IO2 Analog I2C ProxSense Engine (ADC) HW SCL / IO1 MCU or (Master) GPIO Analog - Capacitive offset calibration Cx Reference GND (battery, metal frame, Sensing Pad copper pad) E-field = Capacitance Figure 1.1 Functional Block Diagram for IQS231A/B The IQS231A/B supports relative capacitance measurements for detecting capacitance changes. Basic features of the IQS231A/B include: > Charge-transfer capacitance measurement technology (Analog ProxSense Engine) > Finite state machine to automate detection and environmental compensation without MCU interaction (integrated microprocessor) > Self-capacitance measurements > Signal conditioning to provide signal gain (Analog Capacitive offset calibration) > Signal conditioning to provide offset compensation for parasitic capacitance (Analog Capacitive offset calibration) > Integrated calibration capacitors (Analog Capacitive offset calibration) > Integrated timer for timer triggered conversions > Integrated LDO regulator for increased immunity to power supply noise Copyright Azoteq (Pty) Ltd 2020 IQS231A/B Datasheet Page 2 of 47 All Rights Reserved Revision 2.5 October 2021