AR1000 Datasheet, PDF (8/37 Pages) Microchip Technology – Resistive Touch Screen Controller

7 FUNCTIONAL DESCRIPTION
7.1 Main Schematic
A main application schematic is shown below for the SOIC/SSOP package pinout. See the Pin Diagram section
for the QFN package pinout.
Figure 3 : Main Schematic (SOIC, SSOP package pin out)
7.2 Bill of Materials
Modifying, removing, or adding components may adversely affect touch performance.
Specific manufacturers and part numbers are provided only as a guide. Equivalents can be used.
Label
Qty
Value
C1
1
10 uF
C2
1
0.1 uF
C3, C4, C5¹ _2-3
D1-D8²
4-8
0.01 uF
130 W
R1
1 20K ohm
U1
1
Na
Description
Capacitor – Ceramic, 10uF, 20%, 6.3V, X7R, 0603
Capacitor – Ceramic, 0.1uF, 10%, 16V, X7R, 0603
Capacitor – Ceramic, 0.01uF, 10%, 50V, X7R, 0603
Diode – Bi-dir., 130W, ESD Protection, SOD323
Resistor - 20K ohm, 1/10W, 5%, 0603
Touch controller IC
Manufacturer
AVX
AVX
AVX
NXP
Yageo America
Microchip
Part Number
06036D106MAT2A
0603YC104KAT2A
06035C103KAT2A
PESD5V0S1BA
RC0603JR-0720KL
AR1010 or AR1020
Table 3 : Bill of Materials
Note 1: C5 is only needed for 5-wire applications.
Note 2: D1-D8 are for ESD protection.
 4-wire touch screen, use D1-D4
 5-wire touch screen, use D1-D5
 8-wire touch screen, use D1-D8
The capacitance of alternate ESD diodes may adversely affect touch performance. A lower
capacitance is better. The PESD5V0S1BA parts shown in the reference design have a typical
capacitance of 35pF. Test to ensure that selected ESD protection does not degrade touch
performance.
ESD protection is shown in the reference design, but acceptable protection is dependent on your
specific application. Ensure your ESD solution meets your design requirements.
DS41393A-Page 4
© 2009 Microchip Technology, Inc.