Datasheet AD10242 (Analog Devices) - 7

AD10242 DEFINITION OF SPECIFICATIONS Overvoltage Recovery Time Analog Bandwidth
The amount of time required for the converter to recover to The analog input frequency at which the spectral power of the 0.02% accuracy after an analog input signal of the specified fundamental frequency (as determined by the FFT analysis) is percentage of full scale is reduced to midscale. reduced by 3 dB.
Power Supply Rejection Ratio Aperture Delay
The ratio of a change in input offset voltage to a change in power The delay between the 50% point of the rising edge of the supply voltage. ENCODE command and the instant at which the analog input
Signal-to-Noise and Distortion (SINAD)
is sampled. The ratio of the rms signal amplitude (set at 1 dB below full
Aperture Uncertainty (Jitter)
scale) to the rms value of the sum of all other spectral compo- The sample-to-sample variation in aperture delay. nents, including harmonics but excluding dc.
Differential Nonlinearity Signal-to-Noise Ratio (SNR, without Harmonics)
The deviation of any code from an ideal 1 LSB step. 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-
Encode Pulsewidth/Duty Cycle
nents, excluding the first five harmonics and dc. Pulsewidth high is the minimum amount of time that the ENCODE pulse should be left in Logic “1” state to achieve rated
Spurious-Free Dynamic Range (SFDR)
performance; pulsewidth low is the minimum time that the The ratio of the rms signal amplitude to the rms value of the ENCODE pulse should be left in low state. At a given clock peak spurious spectral component. The peak spurious compo- rate, these specifications define an acceptable encode duty cycle. nent may or may not be a harmonic. SFDR may be reported in dBc (i.e., degrades as signal levels are lowered) or in dBFS
Harmonic Distortion
(always related back to converter full scale). The ratio of the rms signal amplitude to the rms value of the worst harmonic component.
Transient Response
The time required for the converter to achieve 0.02% accu-
Integral Nonlinearity
racy when a one-half full-scale step function is applied to the The deviation of the transfer function from a reference line analog input. measured in fractions of 1 LSB using a “best straight line” deter- mined by a least square curve fit.
Two-Tone Intermodulation Distortion Rejection
The ratio of the rms value of either input tone to the rms value of
Minimum Conversion Rate
the worst third order intermodulation product; reported in dBc. The encode rate at which the SNR of the lowest analog signal frequency drops by no more than 3 dB below the guaranteed limit.
Two-Tone SFDR
The ratio of the rms value of either input tone to the rms value of
Maximum Conversion Rate
the peak spurious component. The peak spurious component The encode rate at which parametric testing is performed. may or may not be an IMD product. Two-tone SFDR may be
Output Propagation Delay
reported in dBc (i.e., degrades as signal levels are lowered) or The delay between the 50% point of the rising edge of the ENCODE in dBFS (always related back to converter full scale). command and the time when all output data bits are within valid logic levels. –6– REV. D Document Outline FEATURES APPLICATIONS GENERAL DESCRIPTION PRODUCT HIGHLIGHTS FUNCTIONAL BLOCK DIAGRAM SPECIFICATIONS ABSOLUTE MAXIMUM RATINGS1 EXPLANATION OF TEST LEVELS PIN CONFIGURATION PIN FUNCTION DESCRIPTIONS DEFINITION OF SPECIFICATIONS Analog Bandwidth Aperture Delay Aperture Uncertainty (Jitter) Differential Nonlinearity Encode Pulsewidth/Duty Cycle Harmonic Distortion Integral Nonlinearity Minimum Conversion Rate Maximum Conversion Rate Output Propagation Delay Overvoltage Recovery Time Power Supply Rejection Ratio Signal-to-Noise and Distortion (SINAD) Signal-to-Noise Ratio (SNR, without Harmonics) Spurious-Free Dynamic Range (SFDR) Transient Response Two-Tone Intermodulation Distortion Rejection Two-Tone SFDR EQUIVALENT CIRCUITS Typical Performance Characteristics THEORY OF OPERATION APPLYING THE AD10242 Encoding the AD10242 Performance Improvements USING THE FLEXIBLE INPUT GROUNDING AND DECOUPLING Analog and Digital Grounding LAYOUT INFORMATION EVALUATION BOARD OUTLINE DIMENSIONS Ordering Guide Revision History