Atmel Evaluation Kit AT91SAM9M10-G45-EK AT91SAM9M10-G45-EK Data Sheet

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SAM9M10 [DATASHEET]

6355F–ATARM–12-Mar-13

The Touch Screen ADC Controller is based on a Successive Approximation Register (SAR) 10-bit Analog-to-Digi-
tal Converter (ADC). It also integrates:

• a 8-to-1 analog multiplexer for analog-to-digital conversions of up to 8

 

analog lines

• 4 power switches that measure both axis positions on the resistive touch screen panel

• 1 additional power switch and an embedded resistor that detects pen-interrupt and pen loss

The conversions extend from 0V to TSADVREF.

The TSADCC supports an 8-bit or 10-bit resolution mode, and conversion results are reported in a common regis-
ter for all channels, as well as in a channel-dedicated register. 

Conversions can be started for all enabled channels, either by a software trigger, by detection of a rising edge on
the external trigger pin TSADTRG or by an integrated programmable timer. When the Touch Screen is enabled, a
timer-triggered sequencer automatically configures the power switches, performs the conversions and stores the
results in dedicated registers.

The TSADCC also integrates a Sleep Mode and a Pen-Detect Mode and connects with one PDC channel. These
features reduce both power consumption and processor intervention.

The TSADCC timings, like the Startup Time and Sample and Hold Time, are fully configurable.

• 8-channel ADC

• Support 4-wire resistive Touch Screen

• 10-bit 384 Ksamples/sec. Successive Approximation Register ADC

• -3/+3 LSB Integral Non Linearity, -2/+2 LSB Differential Non Linearity

• Integrated 8-to-1 multiplexer, offering eight independent 3.3V analog inputs

• External voltage reference for better accuracy on low voltage inputs

• Individual enable and disable of each channel

• Multiple trigger sources

– Hardware or software trigger

– External trigger pin

• Sleep Mode and conversion sequencer

– Automatic wakeup on trigger and back to sleep mode after conversions of all enabled channels