REV. 0

AD9433

–6–

DEFINITIONS OF SPECIFICATIONS

Analog Bandwidth

The analog input frequency at which the spectral power of the

fundamental frequency (as determined by the FFT analysis) is

reduced by 3 dB.

Aperture Delay

The delay between the 50% point of the rising edge of the

ENCODE command and the instant at which the analog

input is sampled.

Aperture Uncertainty (Jitter)

The sample-to-sample variation in aperture delay.

Differential Analog Input Resistance, Differential Analog

Input Capacitance, and Differential Analog Input Impedance

The real and complex impedances measured at each analog

input port. The resistance is measured statically and the capaci-

tance and differential input impedances are measured with a

network analyzer.

Differential Analog Input Voltage Range

The peak-to-peak differential voltage that must be applied to

the converter to generate a fullscale response. Peak differen-

tial voltage is computed by observing the voltage on a single

pin and subtracting the voltage from the other pin, which is

180 degrees out of phase. Peak to peak differential is computed

by rotating the inputs phase 180 degrees and taking the peak

measurement again. Then the difference is computed between

both peak measurements.

Differential Nonlinearity

The deviation of any code width from an ideal 1 LSB step.

Effective Number of Bits

The effective number of bits (ENOB) is calculated from the

measured SNR based on the equation:

ENOB

SNR

dB

Amplitude

Input Amplitude

MEASURED

=

–.

+

Full - Scale

.

176

20

602

log









Encode Pulsewidth/Duty Cycle

Pulsewidth high is the minimum amount of time that the

ENCODE pulse should be left in logic “1” state to achieve

rated performance; pulsewidth low is the minimum time

ENCODE pulse should be left in low state. See timing impli-

specs define an acceptable Encode duty cycle.

Full-Scale Input Power

Expressed in dBm. Computed using the following equation:

Power

V

Z

Full Scale

FullScale

rms

=





















10

0 001

2

log

.

Gain

Gain error is the difference between the measured and ideal

full-scale input voltage range of the ADC.

Harmonic Distortion

The ratio of the rms signal amplitude fundamental frequency to

the rms signal amplitude of a single harmonic component (second,

third, etc.), reported in dBc.

Integral Nonlinearity

The deviation of the transfer function from a reference line

measured in fractions of 1 LSB using a best fit straight line

determined by a least square curve fit.

Minimum Conversion Rate

The encode rate at which the SNR of the lowest analog signal

frequency drops by no more than 3 dB below the guaranteed limit.

Maximum Conversion Rate

The maximum encode rate at which parametric testing is performed.

Output Propagation Delay

The delay between a differential crossing of ENCODE and

ENCODE and the time when all output data bits are within

valid logic levels.

Noise (for Any Range within the ADC)

V

=

Z

0.001

10

FS

– SNR

– Signal

10

NOISE

dBm

dBc

dBFS

××









Where Z is the input impedance, FS is the full scale of the device

for the frequency in question, SNR is the value for the particular

input level, and SIGNAL is the signal level within the ADC

reported in dB below full scale. This value includes both thermal

and quantization noise.

Power Supply Rejection Ratio

The ratio of a change in input offset voltage to a change in

power supply voltage.

Signal-to-Noise and Distortion (SINAD)

The ratio of the rms signal amplitude (set 1 dB below full scale)

to the rms value of the sum of all other spectral components,

including harmonics but excluding dc.

Signal-to-Noise Ratio (without Harmonics)

The ratio of the rms signal amplitude (set at 1 dB below full

scale) to the rms value of the sum of all other spectral compo-

nents, excluding the first five harmonics and dc.

Spurious-Free Dynamic Range (SFDR)

The ratio of the rms signal amplitude to the rms value of the peak

spurious spectral component. The peak spurious component

may or may not be a harmonic. May be reported in dBc (i.e.,

degrades as signal level is lowered), or dBFS (always related back

to converter full scale).

Two-Tone Intermodulation Distortion Rejection

value of the worst third order intermodulation product; reported

Two-Tone SFDR

value of the peak spurious component. The peak spurious com-

ponent may or may not be an IMD product. May be reported in

dBc (i.e., degrades as signal level is lowered), or in dBFS (always

related back to converter full scale).

Worst Other Spur

The ratio of the rms signal amplitude to the rms value of the

worst spurious component (excluding the second and third

harmonic) reported in dBc.