IQ Switch ProxSense Series IQS156 Datasheet IQ Switch - ProxSense Series Minimalist Capacitive Sensor with Compensation for Sensitivity Reducing Objects Unparalleled Features Sub 6uA current consumption Automatic tuning for optimal operation in various environments The IQS156 ProxSense IC is a fully integrated six channel capacitive contact and proximity sensor with market leading sensitivity and automatic tuning to the sense electrodes. The IQS156 provides a minimalist implementation requiring as few as 2 external components. The device is ready for use in a large range of applications while programming options allow customisation for specialized applications. Main Features 6 Channel input device 2 I C data output ATI: Automatic tuning to optimum sensitivity Supply Voltage 3V to 5.5V 8 Power Modes (6A min) IQS143 MSOP10 Internal voltage regulator and reference capacitor Representations only, not Large proximity detection range actual markings Automatic drift compensation Development and Programming tools available (VisualProxSense and USBProg) Small outline MSOP10 Applications White goods and appliances Office equipment, toys, sanitary ware Flame proof, hazardous environment Human Interface Devices Proximity detection that enables backlighting activation (Azoteq Patented) Wake-up from standby applications Replacement for electromechanical switches GUI trigger on proximity detection. Available options T MSOP-10 A IQS156 -40C to 85C IQ Switch ProxSense Series Table 1.1 IQS156 Pin-outs. Functional Overview 2 Pin I C Function 1 Introduction 1 GND Ground The IQS156 is a six channel projected capacitive proximity and touch sensor 4 VDDHI Power featuring internal voltage regulator and Input reference capacitor (C ). s 5 VREG Regulator The device has five dedicated input pins for Pin the connection of the sense electrodes, which comprises of three receivers, and two 2 CRX0 Receiver transmitters. Two output pins are used for Electrode serial data communication through the I2C protocol. 3 CRX1 Receiver The devices automatically tracks slow varying Electrode environmental changes via various filters, detect noise and has an automatic Automatic 9 CRX2 Receiver Electrode Tuning Implementation (ATI) to tune the device for optimal sensitivity. 10 CTX0 Transmitter 1.1 Applicability Electrode All specifications, except where specifically 6 CTX1 Transmitter mentioned otherwise, provided by this Electrode datasheet are applicable to the following ranges: 2 7 SDA I C Data Temperature -40C to +85C 2 8 SCL I C Clock Supply voltage (V ) 3V to 5.5V DDHI 1.2 Pin-outs 2 Analogue Functionality The analogue circuitry measures the 1. GND 10. CTX0 capacitance of the sense electrodes attached 2. CRX0 9. CRX2 3. CRX1 8. SCL to the Cx pins through a charge transfer 4. VDDHI 7. SDA process that is periodically initiated by the 5. VREG 6. CTX1 digital circuitry. The measuring process is referred to a conversion and consists of the discharging of C and Cx, the charging of Cx s Figure 1.1 IQS156 Pin-outs. and then a series of charge transfers from Cx to C until a trip voltage is reached. The s number of charge transfers required to reach the trip voltage is referred to as the Count Values (CS). The capacitance measurement circuitry makes use of an internal C and voltage s reference (V ). REG The analogue circuitry further provides functionality for: Copyright Azoteq (Pty) Ltd 2012. IQS156 Datasheet Page 2 of 24 All Rights Reserved. Revision 1.7 October 2012