Hi,

What is the rise time for AW?

In spec it says that it goes up to 20MHz bandwidth. That's DC-20MHz, correct?

In addition, is there a possibility to extend that bandwidth towards the 50MHz?

## 6402D AWG rise time

### Re: 6402D AWG rise time

Hi Yossi,

The Signal Generator for the 6000 series PicoScopes has a Bandwidth of DC (i.e. setting levels) and 30mHz - 20MHz, and the minimum 10-90% Rise Time is approximately 17.5nS (for a square wave at 20MHz). The Bandwidth specification means that at 20MHz any further frequency components (including harmonics) begin to get rolled-off, i.e. are at the -3dB point, so non-sinusoidal waveforms are already losing their shape at the limits of the bandwidth.

Whether the frequency can be extended depends upon what you require of the generated waveform in terms of integrity and stability, i.e. shape, distortion, noise and jitter. If you want the confidence that your generated signal meets the specifications that we quote, then the answer to your question is No.

However, you can, for example, create a 3 cycle sine-wave in the Arbitrary Waveform Generator and then set the Signal Generator frequency to 16.7MHz, giving you a resulting sine-wave at just over 50MHz, but the waveform has an easily noticeable varying rise and fall time, and clearly visible distortion/noise. For instance, for the PicoScope 6404D model I was using, the rise and fall times were varying by as much as 5%, noise and distortion was between 6-7%, and the jitter was 2-3%. Bear in mind that any other model used could perform significantly worse than the one I was using, and also that the overall level of the signal also drops to about 50%, as the frequency is now beyond the -3dB point. Reducing the number of waveforms in the AWG, and/or reducing the frequency used for the Sig Gen will obviously improve the performance somewhat.

So, it's possible that by using multi-cycle waveforms some customers could find that increasing the frequency of generated sinusoids gives acceptable levels of reduced waveform integrity and stability.

Regards,

Gerry

The Signal Generator for the 6000 series PicoScopes has a Bandwidth of DC (i.e. setting levels) and 30mHz - 20MHz, and the minimum 10-90% Rise Time is approximately 17.5nS (for a square wave at 20MHz). The Bandwidth specification means that at 20MHz any further frequency components (including harmonics) begin to get rolled-off, i.e. are at the -3dB point, so non-sinusoidal waveforms are already losing their shape at the limits of the bandwidth.

Whether the frequency can be extended depends upon what you require of the generated waveform in terms of integrity and stability, i.e. shape, distortion, noise and jitter. If you want the confidence that your generated signal meets the specifications that we quote, then the answer to your question is No.

However, you can, for example, create a 3 cycle sine-wave in the Arbitrary Waveform Generator and then set the Signal Generator frequency to 16.7MHz, giving you a resulting sine-wave at just over 50MHz, but the waveform has an easily noticeable varying rise and fall time, and clearly visible distortion/noise. For instance, for the PicoScope 6404D model I was using, the rise and fall times were varying by as much as 5%, noise and distortion was between 6-7%, and the jitter was 2-3%. Bear in mind that any other model used could perform significantly worse than the one I was using, and also that the overall level of the signal also drops to about 50%, as the frequency is now beyond the -3dB point. Reducing the number of waveforms in the AWG, and/or reducing the frequency used for the Sig Gen will obviously improve the performance somewhat.

So, it's possible that by using multi-cycle waveforms some customers could find that increasing the frequency of generated sinusoids gives acceptable levels of reduced waveform integrity and stability.

Regards,

Gerry

Gerry

Technical Specialist

Technical Specialist