ADUC702 AD [Analog Devices], ADUC702 Datasheet - Page 6

• Manufacturer Part Number: ADUC702
• Description: Precision Analog Microcontroller 12-bit Analog I/O, ARM7TDMI MCU
• Manufacturer: AD [Analog Devices]

ADuC702x Series
TERMINOLOGY
ADC Specifications
Integral Nonlinearity
This is the maximum deviation of any code from a straight line
passing through the endpoints of the ADC transfer function.
The endpoints of the transfer function are zero scale, a point 1/2
LSB below the first code transition and full scale, a point 1/2
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 (0000 . . . 000) to
(0000 . . . 001) from the ideal, i.e., +1/2 LSB.
Gain Error
This is the deviation of the last code transition from the ideal
AIN voltage (Full Scale – 1.5 LSB) after the offset error has been
adjusted out.
Signal to (Noise + Distortion) Ratio
This is the measured ratio of signal to (noise + distortion) at the
output of the ADC. The signal is the rms amplitude of the
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fundamental. Noise is the rms sum of all nonfundamental
signals up to half the sampling frequency (fS/2), excluding dc.
The ratio is dependent upon the number of quantization levels
in the digitisation process; the more levels, the smaller the
quantization noise. The theoretical signal to (noise + distortion)
ratio for an ideal N-bit converter with a sine wave input is given
by:
Signal to (Noise + Distortion) = (6.02N + 1.76) dB
Thus for a 12-bit converter, this is 74 dB.
Total Harmonic Distortion
Total Harmonic Distortion is the ratio of the rms sum of the
harmonics to the fundamental.
DAC SPECIFICATIONS
Relative Accuracy
Relative accuracy or endpoint linearity is a measure of the
maximum deviation from a straight line passing through the
endpoints of the DAC transfer function. It is measured after
adjusting for zero error and full-scale error.
Voltage Output Settling Time
This is the amount of time it takes for the output to settle to
within a 1 LSB level for a full-scale input change..
Preliminary Technical Data