Cable and BPF ( Signal Generator)

Hi,

I am moving this post to the medical forum because that device is supported by that group.  I would suggest also that you take a look at the part number of the transformer coupling on your EVM and look up the datasheet for that transformer.  The last plot at 150K would be much too low a frequency for the passband of the transformer, although that usually just means a loss of amplitude, not a distortion.  A square wave have some 'droop' to it if the frequency were too low for the AC coupling, but the other two plots at 1M should not be too low i would think.  A bandpass filter would turn any of these signals into a sine wave after the harmonics of the fundamental are removed, however.  (In the high speed group, we will usually use an LC bandpass filter with a passband of 3% or 5% from a vendor such as TTE.)

Regards,

Richard P.

Hi,

Bandpass filtering a single tone sinusoidal input signal can help performance and is recommended.  However, the filter can only do so much and the performance of the signal generator is a huge factor.

As Richard stated, applying a square wave or ramp pattern to a bandpass filtered input would convert such signals into sinusoidal signals.  

For our device characterization we use filters from TTE such as the ones shown below:

Thanks,

Christian