vijay_nag
Advanced Member level 4
sinad measurement
Hi,
I am trying to measure the above mentioned dynamic specs of an ADC in Spectre. My ADC is a pipelined, 8-bit and operating at 80MSPS. What i am doing is giving a sinusoidal input of 9MHz and sampling frequency of 60MHz. The input frequency i decided using fin/fs=Mc/M formula. I am using transient simulations with strobestart=1/60MHz and strobestop=128/60MHz and strobe period=1/60MHz. Transient simulations are being run for 128/60MHz. After the simulation i am using the dft function in the calculator for plotting the results. I am entering the following values from=1.667nS(1/60MHz) to=2.1334uS (128/60MHz) ,number of samples=128 and window type as rectangular. This method is explained in the IEEE Std 1241-2000 (which is a standard meant for testing ADCs) and also in this link https://www.designers-guide.org/Forum/YaBB.pl?num=1118555245 . In the result i do not get any noise floor. Am i doing anything wrong?
I also tried to see posts on similar topic in this board. But the answers were not satisfactory.
Regards,
Vijay
Hi,
I am trying to measure the above mentioned dynamic specs of an ADC in Spectre. My ADC is a pipelined, 8-bit and operating at 80MSPS. What i am doing is giving a sinusoidal input of 9MHz and sampling frequency of 60MHz. The input frequency i decided using fin/fs=Mc/M formula. I am using transient simulations with strobestart=1/60MHz and strobestop=128/60MHz and strobe period=1/60MHz. Transient simulations are being run for 128/60MHz. After the simulation i am using the dft function in the calculator for plotting the results. I am entering the following values from=1.667nS(1/60MHz) to=2.1334uS (128/60MHz) ,number of samples=128 and window type as rectangular. This method is explained in the IEEE Std 1241-2000 (which is a standard meant for testing ADCs) and also in this link https://www.designers-guide.org/Forum/YaBB.pl?num=1118555245 . In the result i do not get any noise floor. Am i doing anything wrong?
I also tried to see posts on similar topic in this board. But the answers were not satisfactory.
Regards,
Vijay