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X+

Y+

X-

Y-

AuxilaryInput

AGND

AGND

TSC2005

SNSGND

DGND

1 F

m

1.6VDC

0.1 F

m

Touch

Screen

GPIO

GPIO

SDI

SCLK

SDO

CS

Host

Processor

PINTDAV

RESET

SDO

SCLK

1 F

m

0.1 F

m

1 F

m

0.1 F

m

(

isoptional;

softwareimplementation

pollingoftheStatus

registerispossible)

PINTDAV

TSC2005

SBAS379 – DECEMBER 2006

The TSC2005 is an analog interface circuit for a human interface device. A register-based architecture eases

integration with microprocessor-based systems through a standard SPI bus. All peripheral functions are

controlled through the registers and onboard state machines. The TSC2005 features include:

• Very low-power touch screen controller

• Very small onboard footprint

• Relieves host from tedious routine tasks by flexible preprocessing, saving resources for more critical tasks

• Ability to work on very low supply voltage

• Minimal connection interface allows easiest isolation and reduces the number of dedicated I/O pins required

• Miniature, yet complete; requires no external supporting component. (NOTE: Although the TSC2005 can use

an external reference, it is also possible to use SNSVDD as the reference.)

• Enhanced ESD up to 6kV

• Touch Screen Interface

• Auxiliary Input (AUX)

• Temperature Sensor

• Acquisition Activity Preprocessing

• Internal Conversion Clock

• SPI Interface

Communication to the TSC2005 is done via an SPI serial interface. The TSC2005 is an SPI slave device;

therefore, data is shifted into or out of the TSC2005 under control of the host microprocessor, which also

provides the serial data clock.

Control of the TSC2005 and its functions is accomplished by writing to different registers in the TSC2005. A

simple command protocol compatible with SPI is used to address these registers. A simple serial command

protocol, compatible with SPI, is used to address these registers.

The measurement result is placed in the TSC2005 registers and may be read by the host at any time. This

preprocessing frees up the host so that resources can be redirected for more critical tasks. Two optional signals

are also available from the TSC2005 to indicate that data is available for the host to read. PINTDAV is a

programmable interrupt/status output pin that can be programmed to indicate a pen-touch, data available, or the

combination of both. Figure 19 shows a typical application of the TSC2005.

Figure 19. Typical Circuit Configuration

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