OVERVIEW

X+

Y+

X-

Y-

AuxilaryInput

GND

TSC2008

GND

1 Fto

10 F

m

m

0.1 F

m

Touch

Screen

GPIO

SDI

SCLK

Host

Processor

PENIRQ

SDO

SCLK

1.8VDC

GPIO

SDO

CS

SDI

TSC2008

The TSC2008 is an analog interface circuit for a human interface touch screen device. All peripheral functions

are controlled through the command byte and onboard state machines. While maintaining similarity in hardware,

command, and software to its predecessor, the TSC2046 (or TSC2046E), the TSC2008 includes significant

improvements such as:

• Much stronger and more comprehensive electrostatic discharge (ESD) protection

• Uses only 1/13 power for equivalent performance

• 1/7 bus traffic

• 3/16 size

• Direct 1.8V interface

• Prudent reset scheme

• Saves 1/7 power if 8-bit SDO adjusted output mode used

The TSC2008 consists of the following blocks (refer to the block diagram on the front page):

• Touch Screen Sensor Drivers

• Auxiliary Input (AUX)

• Temperature Sensor

• Acquisition Activity Preprocessing

• Internal Conversion Clock

• SPI Interface

Communication with the TSC2008 is done via an SPI serial interface. The TSC2008 is an SPI slave device;

therefore, data are shifted into or out of the TSC2008 under the control of the host microprocessor, which also

provides the serial data clock.

Control of the TSC2008 and its functions is accomplished by writing to the command register of an internal state

machine. A simple command protocol (compatible with SPI) is used to address this register.

A typical application of the TSC2008 is shown in Figure 20.

Figure 20. Typical Circuit Configuration

Copyright © 2008, Texas Instruments Incorporated

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Product Folder Link(s): TSC2008