AR1020-I/SS Microchip Technology Inc., AR1020-I/SS Datasheet - Page 10

• Manufacturer Part Number: AR1020-I/SS
• Description: Touch Sensing Controller, 20 SSOP .209in TUBE
• Manufacturer: Microchip Technology Inc.

Specifications of AR1020-I/SS

• Operating Voltage: 3.3 to 5.0 Volts ±5%
• Standby Sleep Current: <1 μA
• Operating “no Touch” Current: 3.0 mA Typ.
• Lead Free Status / Rohs Status: RoHS Compliant part Electrostatic Device

7.5 5-wire Touch Sensor Interface
Sensor tail pin-outs can vary by manufacturer and part number. Ensure sensor tail pins for one pair of diagonally
related sensor corners are connected to the controller’s X–/X+ pins and the tail pins for the other pair of diagonally
related corners are connected to the controller’s Y–/Y+ pins. The controller’s X–/X+ and Y–/Y+ pin pairs do not
need to connect to a specific sensor axis. The orientation of controller pins X– and X+ to the two selected
diagonal sensor corners is not important. Likewise, the orientation of controller pins Y– and Y+ to the other two
selected diagonal sensor corners is not important. The sensor tail pin connected to its topsheet must be
connected to the controller’s 5WSX– pin.
Connections to a 5-wire touch sensor are as follows.
Tie unused controller pins SX-, SY-, and SY+ to VSS.
DS41393A-Page 6
Figure 5 : 5-wire Touch Sensor Interface
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.
© 2009 Microchip Technology, Inc.