TSC2005
www.ti.com
SBAS379–DECEMBER 2006
OVERVIEW
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
The TSC2005 consists of the following blocks (refer to the block diagram on the front page):
•
•
•
•
•
•
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.
1.6VDC
1mF
0.1mF
AGND
1mF
0.1mF
1mF
0.1mF
Host
DGND
Processor
SNSGND
PINTDAV
GPIO
GPIO
SDI
X+
Y+
X-
Y-
RESET
SDO
TSC2005
SCLK
SCLK
Touch
Screen
(PINTDAV is optional;
software implementation
polling of the Status
register is possible)
SDO
CS
Auxilary Input
AGND
Figure 19. Typical Circuit Configuration
10
Submit Documentation Feedback
BB [ BURR-BROWN CORPORATION ]
