AD7873 Analog Devices, AD7873 Datasheet - Page 8

• Manufacturer Part Number: AD7873
• Description: Touch Screen Digitizer
• Manufacturer: Analog Devices

Specifications of AD7873

• Resolution (bits): 12bit
• # Chan: 6
• Sample Rate: 125kSPS
• Interface: Ser
• Analog Input Type: SE-Uni
• Ain Range: Uni (Vref),Uni 2.5V
• Adc Architecture: SAR
• Pkg Type: CSP,SOP

AD7873
TERMINOLOGY
Integral Nonlinearity
Integral nonlinearity 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
Differential nonlinearity is the difference between the measured
and the ideal 1 LSB change between any two adjacent codes in
the ADC.
Offset Error
Offset error is the deviation of the first code transition (00…000)
to (00…001) from the ideal, that is, AGND + 1 LSB.
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Gain Error
Gain error is the deviation of the last code transition (111…110)
to (111…111) from the ideal (that is, V
offset error is adjusted out.
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
On resistance is a measure of the ohmic resistance between the
drain and source of the switch drivers.
REF
– 1 LSB) after the