MK712RI IDT, Integrated Device Technology Inc, MK712RI Datasheet
MK712RI
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MK712RI Summary of contents
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TOUCH SCREEN CONTROLLER Description The MK712 Touch Screen Controller IC provides all the screen drive converter and control circuits to easily interface to 4-wire analog resistive touch screens. The IC continually monitors the screen waiting for a ...
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MK712 TOUCH SCREEN CONTROLLER Pin Descriptions Pin Pin Pin Type Number Name 1 NC — 2 INT Output 3 TOUCH Output 4 VDD Power 5 VDD Power 6 XH Touch Screen Pin Connect to X-high on touch screen. (Right side) ...
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MK712 TOUCH SCREEN CONTROLLER IC Operation IDT™ TOUCH SCREEN CONTROLLER TOUCH SCREEN CONTROL 3 MK712 REV N 051310 ...
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MK712 TOUCH SCREEN CONTROLLER Register Description The MK712 register set is designed to be compatible with the Gazelle pen digitizer registers allowing a software driver for the Gazelle digitizer to be used with the MicroClock MK712. The eight 8-bit registers ...
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MK712 TOUCH SCREEN CONTROLLER Rate Register (Register 7) Programming Calculating Points Per Second The formula for determining P.P.S. is: Power-On Reset On application of power, an internal reset is generated that clears all bits in registers 0, 1, and 6. ...
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MK712 TOUCH SCREEN CONTROLLER Recommended Circuit Pen Bounce When the screen is untouched, the Y plate is driven high and the X plate is driven low. When the screen is touched, the X plate is pulled high, which is detected ...
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MK712 TOUCH SCREEN CONTROLLER Optimizing Performance when Reading and Writing Registers Reading and writing the MK712 generates digital noise that may reduce the accuracy of the converter. This noise has several causes, including board layout, data bus ...
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MK712 TOUCH SCREEN CONTROLLER Recommended Method for Reading Points If the user is pressing lightly on the touch screen likely that the screen contact will be intermittent. The screen will bounce, causing false points. This effect can be ...
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MK712 TOUCH SCREEN CONTROLLER Analog to Digital Converter Option The 12-bit ADC converts X and Y co-ordinates at a rate determined by registers 6 and 7. The converter uses a ratiometric technique to give absolute co-ordinates on the screen, largely ...
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MK712 TOUCH SCREEN CONTROLLER Absolute Maximum Ratings Stresses above the ratings listed below can cause permanent damage to the MK712. These ratings, which are standard values for IDT commercially rated parts, are stress ratings only. Functional operation of the device ...
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MK712 TOUCH SCREEN CONTROLLER DC Electrical Characteristics Unless stated otherwise,VDD = 3 5V, T +85°C (automotive) Parameter Operating Voltage Operating Voltage Input High Voltage Input Low Voltage Output High Voltage Output High Voltage Output Low Voltage Input High ...
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MK712 TOUCH SCREEN CONTROLLER AC Electrical Characteristics Unless stated otherwise,VDD = 3 +85°C (automotive) Parameter Input Clock Frequency, pin 18 Input Clock Duty Cycle, pin 18 Output Rise Time Output Fall Time Resolution Non-linearity Touch ...
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MK712 TOUCH SCREEN CONTROLLER Register Interface Timing Number Symbol Read and Write Cycles 1 TRASC 2 TRAHC 3 TRCCY Read Cycle Only 4 TRSCR 5 TRRD 6 TRCHR1 7 TRCHR2 8 TRDC 9 TRDR 10 TRDHC 11 TRDHR Write Cycle ...
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MK712 TOUCH SCREEN CONTROLLER Register Read Register Write IDT™ TOUCH SCREEN CONTROLLER TOUCH SCREEN CONTROL 14 MK712 REV N 051310 ...
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MK712 TOUCH SCREEN CONTROLLER Touchscreen Resistance Graph 1 Touchscreen Resistance Graph 2 IDT™ TOUCH SCREEN CONTROLLER TOUCH SCREEN CONTROL 15 MK712 REV N 051310 ...
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MK712 TOUCH SCREEN CONTROLLER Touchscreen Resistance Graph 3 IDT™ TOUCH SCREEN CONTROLLER TOUCH SCREEN CONTROL 16 MK712 REV N 051310 ...
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MK712 TOUCH SCREEN CONTROLLER Suggested Layout Notes: 1. The 14.318 MHz input clock on pin 18 should have a 33 series termination resistor at its source. Consult IDT for the best way to generate this clock. 2. All digital signals ...
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MK712 TOUCH SCREEN CONTROLLER Package Outline and Package Dimensions Package dimensions are kept current with JEDEC Publication No INDEX AREA IDT™ TOUCH SCREEN CONTROLLER (28-pin SOIC, 300 Mil. Wide Body) Symbol A A1 ...
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MK712 TOUCH SCREEN CONTROLLER Package Outline and Package Dimensions Package dimensions are kept current with JEDEC Publication No INDEX AREA IDT™ TOUCH SCREEN CONTROLLER (28-pin SSOP, 150 Mil. Wide Body) Symbol E1 ...
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MK712 TOUCH SCREEN CONTROLLER Ordering Information Part / Order Number Marking MK712SLF MK712SL MK712SLFTR MK712SL MK712SILF MK712SIL MK712SILFTR MK712SIL MK712RLF MK712RLF MK712RLFTR MK712RLF MK712RWLF MK712RWLF MK712RWLFTR MK712RWLF “LF” suffix to the part number are the Pb-Free configuration and are RoHS ...
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MK712 TOUCH SCREEN CONTROLLER Innovate with IDT and accelerate your future networks. Contact: www.IDT.com For Sales 800-345-7015 408-284-8200 Fax: 408-284-2775 Corporate Headquarters Integrated Device Technology, Inc. www.idt.com © 2006 Integrated Device Technology, Inc. All rights reserved. Product specifications subject to ...