LM8400 National Semiconductor, LM8400 Datasheet - Page 3

• Manufacturer Part Number: LM8400
• Description: Four Wire Resistive Touchscreen Controller with Brownout
• Manufacturer: National Semiconductor

General Description ............................................................................................................................................ 1
Features ............................................................................................................................................................. 1
Block Diagram .................................................................................................................................................... 2
Ordering Information .......................................................................................................................................... 2
Connection Diagrams ......................................................................................................................................... 4
2.0 Pin Descriptions ........................................................................................................................................... 5
Absolute Maximum Ratings ............................................................................................................................... 7
3.0 Electrical Characteristics .............................................................................................................................. 7
4.0 Functional Description .................................................................................................................................. 8
5.0 Oscillator .................................................................................................................................................... 12
6.0 Power Save Mode (Low Power Stand-by) ................................................................................................ 13
7.0 Averaging Algorithm ................................................................................................................................... 13
8.0 Brownout Reset .......................................................................................................................................... 14
9.0 Calibration .................................................................................................................................................. 15
Physical Dimensions ........................................................................................................................................ 19
4.1 General ...................................................................................................................................................... 8
4.2 Advanced Pin Descriptions ....................................................................................................................... 8
4.3 USART Framing Format ............................................................................................................................ 9
7.1 Delta Algorithm ........................................................................................................................................ 13
7.2 Focus Algorithm ....................................................................................................................................... 13
7.3 Communication Modes ............................................................................................................................ 14
9.1 General Calibration Procedures .............................................................................................................. 17
9.2 Calibration Procedures with Coordinates Checking Enabled ................................................................. 18
9.3 Calibration Procedures with Coordinates Checking Disabled ................................................................ 18
4.3.1. Data packet format table .................................................................................................................... 9
4.3.2 Command Bytes .................................................................................................................................. 9
4.3.3 Advanced Command Bytes Descriptions .......................................................................................... 10
Table of Contents
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