AR1000 Datasheet, PDF (4/37 Pages) Microchip Technology – Resistive Touch Screen Controller

8 BASICS OF RESISTIVE SENSORS ................................................................................................... 25
8.1 TERMINOLOGY ................................................................................................................................................25
8.2 GENERAL .......................................................................................................................................................25
8.3 4-WIRE SENSOR.............................................................................................................................................26
8.4 8-WIRE SENSOR.............................................................................................................................................27
8.5 5-WIRE SENSOR.............................................................................................................................................28
8.6 SUMMARY ......................................................................................................................................................28
9 ELECTRICAL SPECIFICATIONS........................................................................................................ 29
9.1 ABSOLUTE MAXIMUM RATINGS(†).....................................................................................................................29
10 PACKAGING .................................................................................................................................... 30
10.1 20 LEAD SOIC ...............................................................................................................................................30
10.2 20 LEAD SSOP ..............................................................................................................................................31
10.3 20 LEAD QFN (ML) ........................................................................................................................................32
FIGURES
Figure 1: Block Diagram................................................................................................................................ 2
Figure 2 : Pin Diagrams – SOIC / SSOP and QFN Packages..................................................................... 3
Figure 3 : Main Schematic (SOIC, SSOP package pin out) ........................................................................ 4
Figure 4 : 4-wire Touch Sensor Interface..................................................................................................... 5
Figure 5 : 5-wire Touch Sensor Interface..................................................................................................... 6
Figure 6 : 8-wire Touch Sensor Interface..................................................................................................... 7
Figure 7 : I²C Timing Diagram – Receive Data............................................................................................ 8
Figure 8 : I²C Timing Diagram – Transmit Data........................................................................................... 8
Figure 9 : I²C Timing Diagram – Touch Report Protocol ............................................................................. 9
Figure 10 : I²C Timing Diagram – Command Protocol................................................................................. 9
Figure 11 : SPI Timing Diagram – Bit Timing............................................................................................... 9
Figure 12 : SPI Timing Diagram – Touch Report Protocol ........................................................................10
Figure 13 : SPI Timing Diagram – Command Protocol.............................................................................. 10
Figure 14: 4-Wire Decoding ........................................................................................................................ 26
Figure 15: 8-Wire Decoding ........................................................................................................................ 27
Figure 16: 5-Wire Decoding ........................................................................................................................ 28
Figure 17 : 20 Lead SOIC Package ........................................................................................................... 30
Figure 18 : 20 Lead SSOP Package.......................................................................................................... 31
Figure 19 : 20 Lead QFN Package ............................................................................................................ 32
TABLES
Table 1: Ordering Part Numbers................................................................................................................... 2
Table 2: Pin Descriptions .............................................................................................................................. 3
Table 3 : Bill of Materials.............................................................................................................................. 4
Table 4 : 4/8-wire vs 5-wire Selection .......................................................................................................... 5
Table 5 : Communication Selection ............................................................................................................. 8
Table 6 : Communication Pins ..................................................................................................................... 8
Table 7 : Touch Coordinate Reporting Protocol......................................................................................... 11
Table 8 : Configuration Registers .............................................................................................................. 12
Table 9 : Command Set Summary............................................................................................................. 18
Table 10 : Sensor Comparison .................................................................................................................. 25
DS41393A-Page iv
© 2009 Microchip Technology, Inc.