ATEVK1012A

Using the EVK1012A: This kit is designed for the evaluation and development of applications using the AT42QT1012-TSHR ('QT1012') Integrated Circuit (IC). Default/shipped setting: User-set Auto-Off Delay set to infinite (J2 Pin1&2 connected by link), Active High Output. Please visit http://www.atmel.com/singletouch for details of this (and similar) products, which includes links to relevant product datasheets. • Insert the battery provided into the battery holder on the EVK1012A board. Ensure that the battery has the correct orientation (negative (-) side to board) or the EVK1012A will not work. • Touch KEY and the LED will light. Release Touch. • Touch KEY and the LED will switch off. If a non-infinite Auto-Off Delay is set and reached (actual time is dependent on Voltage level, Rt and Ct tolerances), the LED will switch off. The LED will light when KEY is touched if the QT1012 is set to Active High Output. If QT1012 is changed to give Active Low Output, then the LED will light until KEY touched. An external power supply can be used instead of a battery. WARNING: if an external power supply is used then the battery MUST be removed. User-Programmed Auto-Off Delay: Schematic: By changing the values of Rt and Ct, the Auto-Off Delay can be changed. Possible Rt and Ct combinations are available using the formula: Rt * Ct = (Delay * k) / 15, where Rt is in kOhm and Ct is in nF and k is constant for a stated voltage and output. For 3V active high output, k = 22.1. For 3V active low output, k = 19.25 (Refer to QT1012 Datasheet for further details) NOTE: (Rt * Ct) / k must be between 4 to 240 for reliable operation. Possible Rt and Ct Auto-Off Delay options at 3V are shown below: 3V Active High 4000 Auto Off Delay (seconds) 3500 3000 2500 22nF 2000 47nF 1500 1000 500 0 0 50 100 150 200 250 Timing Resistor Rt (K ohms) Configuring the EVK1012A: The Auto-Off Delay (stated times ~+/10%) and Output Polarity can be set using the table below: (Remove and refit the battery/power supply when changing Jumper position) Jumper Position (Pins 1-2) 3V Active Low Auto-Off Delay 60 Minutes 60 Minutes 24 Hours 24 Hours J2 * Infinite 15 Minutes Infinite 6 Hours J3 User (Rt,Ct) User (Rt,Ct) User (Rt,Ct) User (Rt,Ct) J4 * 15 Minutes Infinite 6 Hours Infinite Multiplier: (LK1) Output: (LK2) x1: (VSS) x1: (VSS) x24: (VDD) Active High: Active Low: Active High: (VSS) (VDD) (VSS) * Remove Rt when Jumper is in J1, J2 or J4 positions. x24: (VDD) 3500 Auto Off Delay (seconds) J1 * 4000 3000 2500 22nF 2000 47nF 1500 1000 500 Active Low: (VDD) 0 0 50 100 150 200 250 Timing Resistor Rt (K ohms) A User electrode can be connected to the QT1012 using EXT and GND pads: The value of Cs may require changing. (Large pads either side of Cs are available for fitting leaded capacitors in parallel). The EVK1012A can also connect to a User output (using OUT and GND pads). The Auto-Off Delay can be extended or the QT1012 output can be switched off immediately by pulsing the voltage on the delay multiplier resistor RM through J5. (Refer to QT1012 Datasheet for further details) (The values highlighted on the charts can be achieved using supplied kit components) EVK1012A Kit Contents: 1x EVK1012A Evaluation Board 1x CR2032 Battery, 3V, 235mAh 2x AT42QT1012-TSHR ICs Touch Technology Division 1 Mitchell Point 1x EVK1012A User Guide Ensign Way, Hamble Southampton SO31 4RF Rt (10kΩ, 51kΩ, 150kΩ) & Ct (22nF, 47nF) components Packed by: Dated: United Kingdom www.atmel.com Tel: +44 (0)844 894 1920 touch@atmel.com Fax:+44 (0)23 8045 3939 REV 100.0710 © 2010 Atmel Corporation. All rights reserved. Atmel®, Atmel logo and combinations thereof, and others are registered trademarks, QT™, QTouch™ and others are trademarks of Atmel Corporation or its subsidiaries. Other terms and product names may be registered trademarks or trademarks of others.