Positive Gain Error
This is the deviation of the last code transition (011...110 to
011...111) from the ideal VIN+ – VIN– (i.e., +VREF − 1 LSB), after
the zero code error has been adjusted out.
Negative Gain Error
This is the deviation of the first code transition (100...000 to
100...001) from the ideal VIN+ − VIN– (i.e., –VREF + 1 LSB),
after the zero code error has been adjusted out.
Track-and-Hold Acquisition Time
The track-and-hold acquisition time is the minimum time
required for the track-and-hold amplifier to remain in track
mode for its output to reach and settle to within 0.5 LSB of the
applied input signal.
AD7440/AD7450A
Power Supply Rejection Ratio (PSRR)
The power supply rejection ratio is the ratio of the power in
the ADC output at full-scale frequency, f, to the power of a
100 mV p-p sine wave applied to the ADC VDD supply of
frequency fS. The frequency of this input varies from 1 kHz to
1 MHz.
PSRR (dB) = 10log(Pf/PfS)
Pf is the power at frequency f in the ADC output; Pfs is the
power at frequency fS in the ADC output.
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