AD6652BBC datasheet(23/76 Pages) AD

23 / 76 page

AD6652

Rev. 0 | Page 23 of 76

ale

uist zones and alias onto itself. IF

sam

y the bandwidth of the input

HA (sample-and-hold amplifier) and clock jitter. (Jitter adds

g (Oversamp

rs when the

cy components o

low th

ist frequency (Fclo

g inp

e sampled

ut-of-Range Recovery Time

Out-of-range recovery time is th time it takes for the analog-

to-digital co

after a

transient fro

ove

negative full scale, or from 10% below negative full scale to 10%

below positive full scale.

Processing Gain

When the tuned channel occupies less bandwidth than the

input signal, this rejection of out-of-band noise is referred to as

processing gain. By using large decimation factors, this process-

ing gain can improve the SNR of the ADC by 20 dB or more.

The following equation can be used to estimate processing gain:

TERMINOLOGY

Crosstalk

Coupling onto one channel being driven by a (−0.5 dBFS) signal

when the adjacent interfering channel is driven by a full-sc

signal. Measurement includes all spurs resulting from both

direct coupling and mixing components.

IF Sampling (Undersampling)

Due to the effects of aliasing, an ADC is not necessarily limited

to Nyquist sampling. Frequencies above Nyquist are aliased and

appear in the first Nyquist zone (dc to Sample Rate/2). Care

must be taken to limit the bandwidth of the sampled signal so

that it does not overlap Nyq

pling performance is limited b

more noise at higher input frequencies.)

Nyquist Samplin

ling)

Oversampling occu

frequen

f the

analog input signal are be

e Nyqu

/2),

and requires that the analo

ut frequency b

at least

two samples per cycle.

nverter (ADC) to reacquire the analog input

m 10% above positive full scale to 10% ab

⎥

⎦

⎤

⎢

⎣

⎡

Bandwidth

Filter

Rate

Sample

_Gain

Processing

log

Signal-to-Noise Ratio (SNR)

The ratio of the rms value of the measured input signal to the

rms sum of all other spectral components within the pro-

grammed DDC filter bandwidth, excluding the first six

harmonics

cibels (dB).

Two-Tone IMD Rejection

The ratio of the rms value of either input tone to the rms value

of the worst third-order intermodulation product; reported

in dBc.

and dc. The value for SNR is expressed in

ADC EQUIVALENT CIRCUITS

AVDD

Figure 35. Analog Input Circuit

AVDD

Figure 36. Digital Input

VDD

Figure 37. Digital Output

AD6652BBC Datenblatt(PDF) 23 Page - Analog Devices

AD6652BBC Datenblatt(HTML) 23 Page - Analog Devices

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76

Datenblatt Download

Link URL