Features maXTouch Touchscreen Two touchscreens with true 12-bit multiple touch reporting and real-time XY tracking for up to 10 concurrent touches per touchscreen Up to 8.9 inch diagonal screen size supported Number of Channels Electrode grid configurations of up to 18 X and 30 Y lines supported Touchscreens up to 540 channels (subject to other configurations) Up to 64 channels can be allocated as fixed keys (subject to other configurations) maXTouch Two separate self-capacitance channels for use as touch keys or proximity sensors.9710FX 540-channel Signal Processing Advanced digital filtering using both hardware engine and firmware Touchscreen Self-calibration Auto drift compensation Controller Adjacent Key Suppression (AKS ) technology Noise cancellation algorithms for display noise suppression Grip suppression mXT540E-AT Suppression of unintentional touches Reports one-touch and two-touch gestures Automotive Down-scaling and clipping support to match LCD resolution Ultra-fast start-up and calibration for best user experience Version Supports axis flipping and axis switch-over for portrait and landscape modes Fast and powerful 32-bit processor core Scan Speed Maximum single touch >160Hz, subject to configuration Maximum 10 touches >130Hz, subject to configuration Configurable to allow power/speed optimization Programmable timeout for automatic transition from active to idle states Response Times Initial latency <25 ms for first touch from idle, subject to configuration Sensors Shieldless sensor compatible, including fully laminated sensors, touch-on-lens stack-ups and on-cell designs Works with PET or glass sensors, including curved profiles Works with all proprietary sensor patterns recommended by Atmel Supports gloved touch with different materials up to 2.5 mm thickness, subject to configuration Panel Thickness Supports different panel thickness Interfaces 2 I C-compatible slave mode, 400 kHz Dual-rail Power Digital 2.7V to 3.3V nominal Analog 2.7V to 3.3V nominal Package 100-pin TQFP 14 x 14 x 1 mm, 0.5 mm lead pitch 9710FXAT4201/151. Overview of the mXT540E-AT 1.1 Introduction The Atmel maXTouch family of touch controllers has set a new industry benchmark for capacitive touchscreens with their low current consumption, fast response time and high levels of accuracy. The mXT540E-ATs single-chip solution offers the benefits of the maXTouch enhanced architecture on devices with touchscreens up to 8.9 in. diagonal: Patented capacitive sensing method The mXT540E-AT uses a unique charge-transfer acquisition engine to implement Atmels patented QMatrix capacitive sensing method. This allows the measurement of up to 540 mutual capacitance nodes. Coupled with a state- of-the-art CPU, the entire touchscreen sensing solution can measure, classify and track individual finger touches with a high degree of accuracy. Capacitive Touch Engine (CTE) The mXT540E-AT features the E series acquisition engine, which uses an optimal measurement approach to ensure almost complete immunity from parasitic capacitance on the receiver inputs (Y lines). The engine includes sufficient dynamic range to cope with touchscreen mutual capacitances spanning 0.63 pF to 5 pF. This allows great flexibility for use with Atmels proprietary ITO pattern designs. One and two layer ITO sensors are possible using glass or PET substrates. Noise filtering Hardware noise processing in the capacitive touch engine provides enhanced autonomous filtering and allows a broad range of noise profiles to be handled. The result is good performance in the presence of charger and LCD noise. Processing power The main CPU has two powerful, yet low power, microsequencer coprocessors under its control. These combine to allow the signal acquisition, preprocessing, postprocessing and housekeeping to be partitioned in an efficient and flexible way. This gives ample scope for sensing algorithms, touch tracking or advanced shape-based filtering. An in-circuit reflash can be performed over the chips hardware- driven interface. Interpreting user intention Atmel s mutual capacitance method provides unambiguous multitouch performance. Algorithms in the mXT540E-AT provide optimized touchscreen position filtering for the smooth tracking of touches. Stylus support allows stylus touches to be detected and distinguished from other touches, such as finger touches. The suppression of unintentional touches from the users gripping fingers, resting palm or touching cheek or ear also help ensure that the users intentions are correctly interpreted. Self-capacitance channels Two sets of self-capacitance channels allow for the implementation of additional touch keys or proximity sensors using Atmels patented QTouch technology. 1.2 Understanding Unfamiliar Concepts If some of the concepts mentioned in this datasheet are unfamiliar, see the following sections for more information: Appendix C on page 44 for a glossary of terms Appendix D on page 46 for QMatrix technology 2 mXT540E-AT 9710FXAT4201/15