EVAL-AD7933CB AD [Analog Devices], EVAL-AD7933CB Datasheet - Page 11

• Manufacturer Part Number: EVAL-AD7933CB
• Description: 4-Channel, 1.5 MSPS, 12-Bit and 10-Bit Parallel ADCs with a Sequencer
• Manufacturer: AD [Analog Devices]

AD7933/AD7934
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, i.e., AGND + 1 LSB
Offset Error Match
This is the difference in offset error between any two channels.
Gain Error
This is the deviation of the last code transition (111 . . .110) to
(111 . . . 111) from the ideal (i.e., V
error has been adjusted out.
Gain Error Match
This is the difference in gain error between any two channels.
Zero-Code Error
This applies when using the twos complement output coding
option, in particular to the 2 × V
+V
midscale transition (all 0s to all 1s) from the ideal V
i.e., V
Zero-Code Error Match
This is the difference in zero-code error between any two
channels.
Positive Gain Error
This applies when using the twos complement output coding
option, in particular to the 2 × V
+V
code transition (011. . .110) to (011 .. . 111) from the ideal (i.e.,
+V
Positive Gain Error Match
This is the difference in positive gain error between any two
channels.
Negative Gain Error
This applies when using the twos complement output coding
option, in particular to the 2 × V
+V
code transition (100 . . . 000) to (100 . . . 001) from the ideal (i.e.,
−V
out.
REF
REF
REF
REF
REFIN
REF
biased about the V
biased about the V
– 1 LSB) after the zero-code error has been adjusted out.
biased about the V
+ 1 LSB) after the zero-code error has been adjusted
.
REFIN
REFIN
REF
point. It is the deviation of the first
point. It is the deviation of the
point. It is the deviation of the last
REF
REF
REF
REF
input range with −V
input range with −V
input range with −V
– 1 LSB) after the offset
IN
voltage,
REF
REF
REF
to
to
to
Rev. PrG | Page 11 of 32
Negative Gain Error Match
This is the difference in negative gain error between any two
channels.
Channel-to-Channel Isolation
It is a measure of the level of crosstalk between channels. It is
measured by applying a full-scale sine wave signal to the three
nonselected input channels and applying a 50 kHz signal to the
selected channel. The channel-to-channel isolation is defined as
the ratio of the power of the 50 kHz signal on the selected
channel to the power of the noise signal that appears in the FFT
of this channel.
Power Supply Rejection Ratio (PSRR)
It is defined as 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 V
of the input varies from 1 kHz to 1 MHz.
Pf is the power at frequency f in the ADC output; Pf
power at frequency f
Track-and-Hold Acquisition Time
The track-and-hold amplifier returns into track mode and the
end of conversion. The track-and-hold acquisition time is the
time required for the output of the track-and-hold amplifier to
reach its final value, within ±1/2 LSB, after the end of
conversion.
Signal-to-(Noise + Distortion) Ratio (SINAD)
This is the measured ratio of signal-to-(noise + distortion) at
the output of the ADC. The signal is the rms amplitude of the
fundamental. Noise is the sum of all nonfundamental signals up
to half the sampling frequency (f
dependent on the number of quantization levels in the
digitization 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
Thus, for a 12-bit converter, this is 74 dB, and for a 10-bit
converter, this is 62 dB.
PSRR (dB) = 10log(Pf/Pf
Signal-to-(Noise + Distortion) = (6.02 N + 1.76) dB
S
DD
in the ADC output.
Preliminary Technical Data
supply of frequency f
S
)
S
/2), excluding dc. The ratio is
S
. The frequency
S
is the