AD7843_15 Datasheet, PDF (8/21 Pages) Analog Devices – Touch Screen Digitizer

TERMINOLOGY
Integral Nonlinearity
This is the maximum deviation from a straight line passing
through the endpoints of the ADC transfer function. The
endpoints of the transfer function are zero scale, a point 1 LSB
below the first code transition, and full scale, a point 1 LSB
above the last code transition.
Differential Nonlinearity
This is the difference between the measured and the ideal 1 LSB
change between any two adjacent codes in the ADC.
Offset Error
This is the deviation of the first code transition (00…000) to
(00…001) from the ideal, that is, AGND + 1 LSB.
Gain Error
This is the deviation of the last code transition (111…110) to
(111…111) from the ideal (VREF − 1 LSB) after the offset error
has been adjusted out.
AD7843
Track-and-Hold Acquisition Time
The track-and-hold amplifier enters the acquisition phase on
the fifth falling edge of DCLK after the START bit has been
detected. Three DCLK cycles are allowed for the track-and-hold
acquisition time. The input signal is fully acquired to the 12-bit
level within this time even with the maximum specified DCLK
frequency. See the Analog Input section for more details.
On Resistance
This is a measure of the ohmic resistance between the drain and
source of the switch drivers.
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