ad7879-1acbz-rl Analog Devices, Inc., ad7879-1acbz-rl Datasheet - Page 2

• Manufacturer Part Number: ad7879-1acbz-rl
• Description: Low Voltage Controller For Touch Screens
• Manufacturer: Analog Devices, Inc.

AD7879
TABLE OF CONTENTS
Features .............................................................................................. 1
Applications ....................................................................................... 1
Functional Block Diagram .............................................................. 1
General Description ......................................................................... 1
Revision History ............................................................................... 2
Specifications ..................................................................................... 3
Absolute Maximum Ratings ............................................................ 6
Pin Configuration and Function Descriptions ............................. 7
Typical Performance Characteristics ............................................. 8
Terminology .................................................................................... 11
Theory of Operation ...................................................................... 12
Median and Averaging Filters ....................................................... 16
AUX/VBAT/GPIO Pin ................................................................... 17
REVISION HISTORY
10/08—Revision 0: Initial Version
SPI Timing Specifications (AD7879) ......................................... 4
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ESD Caution .................................................................................. 6
Touch Screen Principles ............................................................ 12
Measuring Touch Screen Inputs ............................................... 13
Touch-Pressure Measurement .................................................. 14
Temperature Measurement ....................................................... 14
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C Timing Specifications (AD7879-1) ..................................... 5
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Register Map ................................................................................... 19
Detailed Register Descriptions ..................................................... 20
Control Registers ............................................................................ 24
Serial Interface ................................................................................ 30
Grounding and Layout .................................................................. 35
Outline Dimensions ....................................................................... 36
Auxiliary Input ........................................................................... 17
Battery Input ............................................................................... 17
Limit Comparison ...................................................................... 17
GPIO ............................................................................................ 17
Control Register 1 ...................................................................... 24
Control Register 2 ...................................................................... 26
Control Register 3 ...................................................................... 27
Interrupts ..................................................................................... 28
Synchronizing the AD7879 to the Host CPU ......................... 29
SPI Interface ................................................................................ 30
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Chip Scale Packages ................................................................... 35
WLCSP Assembly Considerations ........................................... 35
Ordering Guide .......................................................................... 36
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C-Compatible Interface .......................................................... 32