Rainbow Electronics AT84AD004 - Manual (Page 45)

45
AT84AD004
5390A–BDC–06/04
Figure 47. Data Output Buffer Model
Definitions of Terms
VCCO
GNDO
DOAIO, DOAI7
DOBIO, DOBI7
DOAION, DOAI7N
DOBION, DOBI7N
Table 14. Definitions of Terms
Abbreviation Definition Description
BER Bit Error Rate
The probability of exceeding a specified error threshold for a sample at a maximum specified
sampling rate. An error code is a code that differs by more than ±4 LSB from the correct code
DNL
Differential
Non-Linearity
The differential non-linearity for an output code i is the difference between the measured step
size of code i and the ideal LSB step size. DNL (i) is expressed in LSBs. DNL is the
maximum value of all DNL (i). A DNL error specification of less than 1 LSB guarantees that
there are no missing output codes and that the transfer function is monotonic
ENOB
Effective Number of
Bits
Where A is the actual input amplitude and Fs is
the full scale range of the ADC under test
FPBW
Full Power Input
Bandwidth
The analog input frequency at which the fundamental component in the digitally
reconstructed output waveform has fallen by 3 dB with respect to its low frequency value
(determined by FFT analysis) for input at full-scale -1 dB (-1 dBFS)
IMD
Inter-Modulation
Distortion The two tones intermodulation distortion (IMD) rejection is the ratio of either of the two input
tones to the worst third order intermodulation products
INL
Integral
Non-Linearity
The integral non-linearity for an output code i is the difference between the measured input
voltage at which the transition occurs and the ideal value of this transition. INL (i) is
expressed in LSBs and is the maximum value of all |INL (i)|
JITTER
Aperture
uncertainty The sample-to-sample variation in aperture delay. The voltage error due to jitters depends on
the slew rate of the signal at the sampling point
NPR Noise Power Ratio
The NPR is measured to characterize the ADC’s performance in response to broad
bandwidth signals. When applying a notch-filtered broadband white noise signal as the input
to the ADC under test, the Noise Power Ratio is defined as the ratio of the average out-of-
notch to the average in-notch power spectral density magnitudes for the FFT spectrum of the
ADC output sample test
ENOB
SINAD 1.76 – 20
A
Fs /2
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