DESCRIPTION:

The ADS7843 is a 12-bit sampling analog-to-digital
converter (ADC) with a synchronous serial interface
and low on-resistance switches for driving touch
screens. Typical power dissipation is 750mW at a
125kHz throughput rate and a +2.7V supply. The
reference voltage (VREF) can be varied between 1V and
+VCC, providing a corresponding input voltage range
of 0V to VREF. The device includes a shutdown mode
which reduces typical power dissipation to under
0.5mW. The ADS7843 is guaranteed down to 2.7V
operation.
Low power, high speed, and on-board switches make
the ADS7843 ideal for battery operated systems such
as personal digital assistants with resistive touch screens
and other portable equipment. The ADS7843 is available
in a 16-lead SSOP package and is guaranteed
over the –40°C to +85°C temperature range.

FEATURES:

• 4-WIRE TOUCH SCREEN INTERFACE
• RATIOMETRIC CONVERSION
• SINGLE SUPPLY: 2.7V to 5V
• UP TO 125kHz CONVERSION RATE
• SERIAL INTERFACE
• PROGRAMMABLE 8- OR 12-BIT RESOLUTION
• 2 AUXILIARY ANALOG INPUTS
• FULL POWER-DOWN CONTROL

• PERSONAL DIGITAL ASSISTANTS
• PORTABLE INSTRUMENTS
• POINT-OF-SALES TERMINALS
• PAGERS
• TOUCH-SCREEN MONITORS