mk712 Integrated Device Technology, mk712 Datasheet
mk712
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mk712 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 touch. In this mode, the supply current is typically 0.5µA. When ...
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... Interrupts are controlled by register 6 (see Register Description). The INT pin (pin 2) goes high to signal an interrupt. Interrupts are then cleared by reading any register. However, if the MK712 is in the process of generating an interrupt during a read cycle, then the interrupt is not cleared and INT will stay high. This internal process may take 100ns, and so to guarantee that the interrupt is cleared, two successive read cycles may be necessary. IDT™ ...
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... MK712 TOUCH SCREEN CONTROLLER IC Operation IDT™ / ICS™ TOUCH SCREEN CONTROLLER TOUCH SCREEN CONTROL 3 MK712 REV L 070805 ...
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... 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 are defined below: IDT™ / ICS™ TOUCH SCREEN CONTROLLER ...
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... PPS. Note that clearing register 6 puts the IC into the power down condition. Initializing the MK712 The interrupt on the MK712 can only be cleared by reading a register or by writing register 6 to the power down condition. After a fault condition, initialize the MK712 by writing register 6 to zero and then writing register 6 to the desired value. This will always clear pending interrupts. IDT™ ...
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... 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 by the MK712. This initiates a conversion (as long as periodic conversions are enabled). Some de-bounce is provided by the time constant of the screen decoupling capacitors combined with the screen resistance ...
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... 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 loading, and power supply voltage. By appropriately timing the register operations, the effects of this noise can be minimized ...
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... Warning–When Using a Switching Regulator Power Supply When using the MK712 in a system where the power is supplied by a switching regulator, do not perform screen conversions when the regulator is operating in the power saving mode. Some switching regulators feature a low power mode (for example, Linear Technology’ ...
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... In addition, the interconnect resistances on the screen also account for about 20% of the total resistance. This means that approximately the bottom 10% and top 10% of full scale are inaccessible. The converter is guaranteed to be monotonic, with no missing codes. IDT™ / ICS™ TOUCH SCREEN CONTROLLER TOUCH SCREEN CONTROL 9 MK712 REV L 070805 ...
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... 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 ICS commercially rated parts, are stress ratings only. Functional operation of the device at these or any other conditions above those indicated in the operational sections of the specifications is not implied. ...
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... PPS At VDD=3.3 V, Note 3 Standby, Clock, Note 4 Standby, Note 5 Power down, PD=0 or PD=1, no clock I Each output TOUCH SCREEN CONTROL Min. Typ. Max. Units 3.0 5.5 V 3.135 5 0.8 V VDD-0.4 V 2.4 V 0.4 V 1.9 V 0.4 V 2 0.5 3 µA 0.5 3 µA 0.2 3 µA ± MK712 REV L 070805 ...
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... A Symbol Conditions Note 0.8 to 2.0 V, VDD 2.0 to 0.8 V, VDD Monotonic, Note 2 12 TOUCH SCREEN CONTROL Min. Typ. Max. Units 12 14.32 20 MHz bits ±2 LSB Ω 100 2000 MK712 REV L 070805 ...
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... Data Hold from WR High Data Setup to CS High 13 TOUCH SCREEN CONTROL Min. Max. Units Note MK712 REV L 070805 ...
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... MK712 TOUCH SCREEN CONTROLLER Register Read Register Write IDT™ / ICS™ TOUCH SCREEN CONTROLLER TOUCH SCREEN CONTROL 14 MK712 REV L 070805 ...
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... MK712 TOUCH SCREEN CONTROLLER Touchscreen Resistance Graph 1 Touchscreen Resistance Graph 2 IDT™ / ICS™ TOUCH SCREEN CONTROLLER TOUCH SCREEN CONTROL 15 MK712 REV L 070805 ...
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... MK712 TOUCH SCREEN CONTROLLER Touchscreen Resistance Graph 3 IDT™ / ICS™ TOUCH SCREEN CONTROLLER TOUCH SCREEN CONTROL 16 MK712 REV L 070805 ...
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... The 14.318 MHz input clock on pin 18 should have a 33Ω series termination resistor at its source. Consult ICS for the best way to generate this clock. 2. All digital signals should be kept well away from pins 10, and 11, and any traces connected to those pins. IDT™ / ICS™ TOUCH SCREEN CONTROLLER TOUCH SCREEN CONTROL 17 MK712 REV L 070805 ...
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... TOUCH SCREEN CONTROL Millimeters Inches Min Max Min Max — 2.65 — 0.104 0.10 — 0.004 0.010 -- 1.50 0.0040 — 0.33 0.51 0.013 0.020 0.18 0.32 0.007 0.013 17.70 18.40 0.697 0.724 7.40 7.60 0.291 0.299 1.27 Basic .050 Basic 10.00 10.65 0.394 0.419 0.25 0.75 0.010 0.029 0.40 1.27 0.016 0.050 0° 8° 0° 8° MK712 REV L 070805 ...
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... C 19 TOUCH SCREEN CONTROL Millimeters Min Max Min A 1.35 1.75 0.053 A1 0.10 0.25 0.004 0.20 0.30 0.008 C 0.18 0.25 0.007 D 9.80 10.00 0.386 E 5.80 6.20 0.228 E1 3.80 4.00 0.150 e .635 Basic .025 Basic L 0.40 1.27 0.016 α 0° 8° 0° L MK712 Inches Max 0.069 0.010 .059 0.012 0.010 0.394 0.244 0.157 0.050 8° c REV L 070805 ...
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... MK712SI MK712R MK712R MK712RTR MK712R MK712RLF MK712RLF MK712RLFTR MK712RLF MK712RI MK712RI MK712RITR MK712RI MK712RWLF MK712RWLF MK712RWLFTR MK712RWLF Parts that are ordered with a “LF” suffix to the part number are the Pb-Free configuration and are RoHS compliant. While the information presented herein has been checked for both accuracy and reliability, Integrated Circuit Systems (ICS) assumes no responsibility for either its use or for the infringement of any patents or other rights of third parties, which would result from its use ...
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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. 6024 Silver Creek Valley Road San Jose, CA 95138 United States 800 345 7015 +408 284 8200 (outside U.S.) © ...