AT42QT4160

Features • QField™ Touchscreen: – Up to 4.8 inches diagonal screen size supported • Technology: – Patented spread-spectrum charge-transfer (transverse mode) • Panel Materials: – Plastic, glass, composites, painted surfaces (low particle density metallic paints possible) Adjacent Metal: – Compatible with grounded metal immediately next to sensing channels Panel Thickness: – 1 to 2 mm glass, 0.5 to 1.5 mm plastic Interface: – I2C-compatible slave mode, 100 kHz or 400 kHz Moisture Tolerance: – Best in class Power: – 1.8V to 5.5V (2.5V to 5.5V in high speed mode) Packages: – 32-pin 5 x 5 mm MLF RoHS compliant Signal Processing: – Self-calibration, auto drift compensation, noise filtering Applications: – Mobile electronics, terminals, appliances Patents: – QMatrix™ (patented Charge-transfer method) – QField (patented Charge-transfer method, patent-pending QField optimized for one-layer sensor element designs) • • • • • • • • • QField™ 10-bit Touchscreen Sensor IC AT42QT4160 Summary 1. Pin-out and Pin Listing Descriptions 1.1 Device Pin-out Y3B SDA SCL RST Y1A Y2A 1 2 3 4 5 6 7 8 Y0A Y2B Y1B Y0B A0 Vss Vdd Vdd Vdd N/C Note: This is a summary document. A complete document is available under NDA. For more information contact www.atmel.com/touchscreen. Y3A CHANGE Vss Vdd Vss Vdd N/C N/C 32 31 30 29 28 27 26 25 24 23 AT42QT4160 22 21 20 19 18 17 9 10 11 12 13 14 15 16 Vss X1 X0 SMP VREF X2 N/C X3 9507AS–AT42–10/08 1.2 Pin Listing Description Pin Listing Name Y3A CHANGE Vss Vdd Vss Vdd N/C N/C Vss VREF SMP X0 X1 X2 X3 N/C N/C Vdd Vdd Vdd Vss A0 Y0B Y1B Y2B Y3B SDA SCL RST Y0A Y1A Y2A Type O OD P P P P O O P I O O O O O O O P P P P I I/O I/O I/O I/O OD OD I O O O 2 Table 1-1. Pin 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 Comments Y line connection State change notification Supply ground Power Supply ground Power Not connected Not connected Supply ground Supply ground Sample output X matrix drive line X matrix drive line X matrix drive line X matrix drive line Not connected Not connected Power Power Power Supply ground I C-compatible address select Y line connection Y line connection Y line connection Y line connection Serial Interface Data Serial Interface Clock Reset low; has internal 30k - 60k pull-up Y line connection Y line connection Y line connection If Unused, connect To... Leave open Leave open – – – – Leave open Leave open – – – Leave open Leave open Leave open Leave open Leave open Leave open – – – – – Leave open Leave open Leave open Leave open – – Leave open or Vdd Leave open Leave open Leave open I O OD 2 Input only Output only, push-pull Open drain output I/O X P Input and output Clock resonator Ground or power AT42QT4160 9507AS–AT42–10/08 AT42QT4160 1.3 Wiring Diagram Wiring Diagram Figure 1-1. Vunreg VDD VREG follow regulator manufacturer's recommended values for input and output bypass capacitors; keep output capacitor close to pins 4 and 6. If not possible, add a 100nF capacitor next to those pins. N/C N/C N/C N/C RST VDD QT4160 I2C-COMPATIBLE SDA SCL VDD Rx3 Rx2 Rx1 Rx0 Ry0 Cs0 CHANGE Cs1 Ry1 CHANGE I C-COMPATIBLE ADDRESS SELECT 2 Ry2 Cs2 Ry3 Cs3 NOTES: Rs3 Rs2 Rs1 Rs0 1) The central pad on the underside of the chip is a Vss pin and should be connected to ground. Do not put any other tracks underneath the body of the chip. 2) It is important to place all Cs, Rs, Rx and Ry components physically near to the chip. Suggested regulator manufacturers: • Torex (XC6215 series) • Seiko (S817 series) • BCDSemi (AP2121 series) MATRIX Y SCAN IN Rc MATRIX X DRIVE Rp Rp 3 9507AS–AT42–10/08 2. Overview The AT42QT4160 (QT4160) QField IC is a self-contained capacitive touchscreen controller that employs Atmel’s patented transverse charge-transfer (QT™) acquisition method. The controller senses changes in electrical charge forced across two electrode elements by a pulse edge (see Figure 2-1). Figure 2-1. Field Flow Between X and Y Elements overlying panel X eleme nt Y elem ent The touchscreen is critical to the design and is specially patterned to improve linearity, limit hand shadow and keep the number of connection lines to a minimum. The device includes all signal processing functions necessary to provide stable sensing under a wide variety of changing conditions. Only a few external parts are required for operation. The entire circuit can be built within a few square centimeters of single-sided PCB area. CEM-1 and FR1 punched, single-sided materials can be used for the lowest possible cost. The PCB’s rear can be mounted flush on the back of a glass or plastic panel using a conventional adhesive, such as 3M VHB two-sided adhesive acrylic film. The device uses an I2C-compatible interface to allow channel data to be extracted and to permit touchscreen parameter setup. The command structure is designed to minimize the amount of data traffic while maximizing the amount of information conveyed. In addition to normal operating and setup functions the device can also report back actual signal strengths. 4 AT42QT4160 9507AS–AT42–10/08 AT42QT4160 3. Revision History Revision No. Revision AS – October 2008 History Initial release for chip revision 7.0 5 9507AS–AT42–10/08 Headquarters Atmel Corporation 2325 Orchard Parkway San Jose, CA 95131 USA Tel: 1(408) 441-0311 Fax: 1(408) 487-2600 International Atmel Asia Unit 01-05 & 16, 19/F BEA Tower, Millennium City 5 418 Kwun Tong Road Kwun Tong Kowloon Hong Kong Tel: (852) 2245-6100 Fax: (852) 2722-1369 Touch Technology Division 1 Mitchell Point Ensign Way Hamble Southampton Hampshire SO31 4RF United Kingdom Tel: (44) 23-8056-5600 Fax: (44) 23-8045-3939 Atmel Europe Le Krebs 8, Rue Jean-Pierre Timbaud BP 309 78054 Saint-Quentin-enYvelines Cedex France Tel: (33) 1-30-60-70-00 Fax: (33) 1-30-60-71-11 Atmel Japan 9F, Tonetsu Shinkawa Bldg. 1-24-8 Shinkawa Chuo-ku, Tokyo 104-0033 Japan Tel: (81) 3-3523-3551 Fax: (81) 3-3523-7581 Product Contact Web Site www.atmel.com Technical Support touch@atmel.com Sales Contact www.atmel.com/contacts Literature Requests www.atmel.com/literature Disclaimer: T he information in this document is provided in connection with Atmel products. No license, express or implied, by estoppel or otherwise, to any intellectual property right is granted by this document or in connection with the sale of Atmel products. E XCEPT AS SET FORTH IN ATMEL’S TERMS AND CONDITIONS OF SALE LOCATED ON ATMEL’S WEB SITE, ATMEL ASSUMES NO LIABILITY WHATSOEVER AND DISCLAIMS ANY EXPRESS, IMPLIED OR STATUTORY WARRANTY RELATING TO ITS PRODUCTS INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTY OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT. IN NO EVENT SHALL ATMEL BE LIABLE FOR ANY DIRECT, INDIRECT, CONSEQUENTIAL, PUNITIVE, SPECIAL OR INCIDENTAL DAMAGES (INCLUDING, WITHOUT LIMITATION, DAMAGES FOR LOSS OF PROFITS, BUSINESS INTERRUPTION, OR LOSS OF INFORMATION) ARISING OUT OF THE USE OR INABILITY TO USE THIS DOCUMENT, EVEN IF ATMEL HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. A tmel makes no representations or warranties with respect to the accuracy or completeness of the contents of this document and reserves the right to make changes to specifications and product descriptions at any time without notice. Atmel does not make any commitment to update the information contained herein. Unless specifically provided otherwise, Atmel products are not suitable for, and shall not be used in, automotive applications. Atmel’s products are not intended, authorized, or warranted for use as components in applications intended to support or sustain life. © 2008 Atmel Corporation. All rights reserved. Atmel®, Atmel logo and combinations thereof, and others are registered trademarks, Adjacent Key Suppression ™, AKS ™, QT™, QField ™, QMatrix™, QTouch ™and others are trademarks of Atmel Corporation or its subsidiaries. Other terms and product names may be registered trademarks or trademarks of others. 9507AS–AT42–10/08