snoop835
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Hi everyone,
I am a beginner in Analog IC Design. I want to run FFT analysis using HSpice to determine the dynamic Range of 1st Order Delta Sigma modulator. The syntax I used is as followed.
.fft v(output) np=4096 start=0m stop=1m freq=1k window=rect
This analysis is run in parallel with transient analysis and the output for FFT analysis is a graph X-axis(Frequency) versus y-axis(magnitude in dB).
The question is, how do I measure the Spurious Free Dynamic Range from the output plot?
I know that from definition, Spurious Free Dynamic Range is a difference between highest peak of fundamental frequency(1kHz in my example) and the highest peak of second harmonics. From the FFT output, I can determine the highest peak for fundamental frequency but how do I determine the highest peak for second harmonic? Im a bit confused at this part!
Anyone can help? Is there any good tutorial for this measurement?
regards,
leyman
I am a beginner in Analog IC Design. I want to run FFT analysis using HSpice to determine the dynamic Range of 1st Order Delta Sigma modulator. The syntax I used is as followed.
.fft v(output) np=4096 start=0m stop=1m freq=1k window=rect
This analysis is run in parallel with transient analysis and the output for FFT analysis is a graph X-axis(Frequency) versus y-axis(magnitude in dB).
The question is, how do I measure the Spurious Free Dynamic Range from the output plot?
I know that from definition, Spurious Free Dynamic Range is a difference between highest peak of fundamental frequency(1kHz in my example) and the highest peak of second harmonics. From the FFT output, I can determine the highest peak for fundamental frequency but how do I determine the highest peak for second harmonic? Im a bit confused at this part!
Anyone can help? Is there any good tutorial for this measurement?
regards,
leyman