This preview shows page 1 out of 2 pages.

Save
View full document
View full document
Premium Document
Do you want full access? Go Premium and unlock all 2 pages.
Access to all documents
Download any document
Ad free experience
Premium Document
Do you want full access? Go Premium and unlock all 2 pages.
Access to all documents
Download any document
Ad free experience

Unformatted text preview:

1UNIVERSITY OF CALIFORNIA College of Engineering Department of Electrical Engineering and Computer Sciences NTU 247 Homework 6 EECS 247 B. E. BOSER Due Thursday, Dec 7, 2006 Fall 2006 1. Download the datasheet of the AD7677 A/D converter from www.analog.com. a) Using the given code histograms for DC input, calculate the converter’s input referred thermal noise in LSB rms. (Follow the method presented in: S. Ruscak and L. Singer, "Using Histogram Techniques to Measure A/D Converter Noise," - available at http://www.analog.com/library/analogDialogue/archives/29-2/cnvtrnoise.html). b) Using the data from the typical DNL plot, estimate the expected quantization noise in LSB rms error of the converter. Assume that the DNL is distributed uniformly over the bounds seen in the DNL plot. c) Combine the results of a) and b) to obtain an estimate for the converter’s SNR. Does this number agree with the typical value given in the data sheet? d) What is the ENOB of this converter? e) The typical low frequency DFT plot of the AD7677 shows a dominant 3rd harmonic. Use your analysis from problem 2 of homework 4 to estimate the converter’s SFDR from the peak INL seen in the given typical INL plot. Does this number agree with the specified typical SFDR value? 2. The sigma-delta modulator below employs an N-bit ADC for increased resolution, but only a 1-bit DAC is used to avoid distortion due to DAC nonlinearity. The remaining N-1 bits of ADC outputs serve as an estimate of the quantization error. a) Find Y(z) as a function of the input X(z), quantization error E1(z) and ADC truncation error E2(z). What is the optimal value for G in order to eliminate the truncation error in Y(z)? b) Compute the dynamic range of the converter as a function of N and the oversampling ratio M. Assume optimal setting of G calculated in a) and an ideal (i.e. brickwall) decimation filter. 1/(z-1)N-bitADC1-bitDAC1/zxGX(z)MSBNN-11_++_+_Y(z)2Hint: E1(z) and E2(z) can be modeled as additive white noise sources. As a result the system can be modeled as a linearized schematic as following. Note that an ideal DAC doesn’t introduce any error. 1/(z-1) 1/zxGX(z)E1(z)_++_+_Y(z)++E2(z)++A(z)B(z)


View Full Document

Berkeley ELENG 247A - Homework

Documents in this Course
Lecture 8

Lecture 8

29 pages

Lecture 8

Lecture 8

35 pages

Lecture 8

Lecture 8

31 pages

Lecture 9

Lecture 9

36 pages

Lecture 7

Lecture 7

34 pages

Load more
Download Homework
Our administrator received your request to download this document. We will send you the file to your email shortly.
Loading Unlocking...
Login

Join to view Homework and access 3M+ class-specific study document.

or
We will never post anything without your permission.
Don't have an account?
Sign Up

Join to view Homework 2 2 and access 3M+ class-specific study document.

or

By creating an account you agree to our Privacy Policy and Terms Of Use

Already a member?