ADC and DAC Standards Update

Transcription

1 ADC and DAC Standards Update

2 Revised ADC Standard 2010 New terminology to conform to Std-1057 SNHR became SNR SNR became SINAD Added more detailed test-setup descriptions Added more appendices Reorganized some of the presentation based on lessons learned while rewriting Final balloting just completed

3 1241 Table of Contents Excerpt 1 Overview Scope Analog-to-digital converter background Guidance to the user Interfacing Test conditions Electrical environment Test equipment Test selection Manufacturer-supplied information 15 4 General test methods Test setup Sinewave test setup Arbitrary signal test setup Step signal setup Taking a record of data Use of output decimation in taking a record of data Equivalent time sampling and undersampling Extraction method Comments on the extraction method for equivalent time sampling Alternate extraction method Comments on alternate extraction method 39

4 1241 Table of Contents Excerpt 5 Sinewave testing and fitting 5.1 Curve fitting test method 5.4 Selecting signal amplitudes 5.5 Presenting sinewave data 5.6 Impurities of sinewave sources 5.7 Estimating impurity problems from sine-fitting results 5.8 Measuring and controlling sinewave impurities 6 Locating code transitions 6.1 Locating code transitions using a feedback loop 6.2 Alternate code transition location method based on ramp histogram 6.3 Alternate code transition location method, based on sine-wave histogram 6.4 Determining the static transfer curve 7 Analog input Static input resistance 7.2 Static input impedance versus input signal level 7.3 Static input current 7.4 Static gain and offset 8 Linearity 8.1 Integral nonlinearity 8.2 Absolute accuracy error 8.3 Differential nonlinearity and missing codes 8.4 Example INL and DNL data 8.5 Monotonicity

5 1241 Table of Contents Excerpt 8.6 Hysteresis 8.7 Harmonic and spurious distortion Total harmonic distortion Spurious free dynamic range 8.8 Intermodulation distortion Intermodulation distortion test method using two tones Intermodulation distortion test methods using more than two tones 8.9 Noise power ratio (NPR) 9 Noise (total) 9.1 Signal-to-noise and distortion ratio (SINAD) 9.2 Signal-to-noise ratio (SNR) 9.3 Effective number of bits (ENOB) Effects of harmonic distortion on sinewave tests 9.4 Random noise 10 Step response parameters 10.2 Slew rate limit 10.3 Settling time parameters 10.4 Transition duration of step response 10.5 Overshoot and precursors

6 1241 Table of Contents Excerpt 11 Frequency response parameters 11.1 Bandwidth (BW) 11.2 Gain error (gain flatness) 11.3 Frequency response and gain from step response 12 Differential gain and phase 13 Aperture effects 13.1 Aperture duration 13.2 Aperture delay 13.3 Aperture jitter 14 Additional tests and specification 14.1 Digital logic signals 14.2 Pipeline delay 14.3 Out-of-range recovery 14.4 Differential input specifications 14.6 Power supply parameters Annex A (Informative) ADC Architectures Annex B (Informative) Sinewave fitting algorithms Annex C (Normative) Discrete Fourier transforms and windowing Annex D (Informative) Presentation of Sinewave data

7 Some ADC Critical Parameters DNL ENOB NPR INL DG SINAD THD IMD SFDR = differential nonlinearity = effective number of bits = noise power ratio = integral nonlinearity = differential gain error = signal-to-noise and distortion ratio = total harmonic distortion = intermodulation distortion = differential phase error

8 Setup for Sinewave Ttesting

9 Setup for Arbitrary Signal Testing

10 DAC Standard Completely New Structure similar to ADC Standard. Attempt to finish this year. Waveform recorder is the primary test instrument Does not have to be as accurate as the DAC. Test signals are sinewaves and steps as in ADC standard but generated is bit stream.

11 DAC Standard Table of Contents Excerpt 1. Overview Scope and purpose Digital to analog converter and analog to digital converter differences and similarities Digital to analog converter background Guidance to the user Interfacing Coding Test conditions Test equipment Test selection Manufacturer supplied information Test methods Fitting sinewaves 39

12 DAC Standard Table of Contents Excerpt 6. Digital input Coding Clock and data feedthrough Static input parameters Timing parameters Analog inputs Analog output (single-ended and differential) Output impedance test method Short circuit current test method Compliance voltage test method Load current test method for voltage-source DACs Test method for dynamic range Static gain and offset test method Dynamic gain error Integral nonlinearity test method 49

13 DAC Standard Table of Contents Excerpt 10.2 Differential nonlinearity Monotonicity Spurious free dynamic range Noise Signal to noise and distortion ratio Test method for SINAD in the frequency domain Test method for SINAD in the time domain Signal to noise ratio Effective number of bits Noise power ratio Harmonic and spurious distortion Total harmonic distortion Intermodulation distortion Glitches /f Noise 62

14 DAC Standard Table of Contents Excerpt 13. Step response parameters Settling time parameters Transition duration Overshoot and precursors Interference-related DAC parameters Multitone power ratio Crosstalk (channel separation, channel isolation) Channel matching Channel skew Frequency response parameters Reference input bandwidth Digital-to-analog-conversion frequency response Differential gain and phase Power supply parameters 78 Annex A (Informative) DAC Architectures 83 Annex B (Informative) Sinewave fitting algorithms 88 Annex C (Informative): Discrete Fourier transforms and windowing 88 Annex D (Informative) Software considerations 100

15 General DAC Model Used in Standard Figure 5 - Block diagram interpolating DAC. If K = 1, the DAC is a noninterpolating DAC

16 Critical DAC parameters ACLR = adjacent channel leakage power ratio CM = channel matching DG = differential gain DNL = differential nonlinearity DP = differential phase ENOB = effective number of bits GE = gain error IMD = Intermodulation distortion INL = integral nonlinearity OV = Output voltage compliance range MTPR = Missing Tone Power Ratio SINAD = signal-to-noise and distortion ratio SFDR = spurious free dynamic range SNR = signal to noise ratio T S = settling time THD = total harmonic distortion THD+N = THD plus noise TR = transient response

17 DAC Test Setup Filter here to remove fundamental frequency and reduce dynamic range requirement of waveform recorder.