Is AD9746 monotonic?

Hi qNimble ,

The AD9746 DAC is inherently monotonic by design. They are guaranteed to be monotonic once they're released to the market. There's no INL/DNL graph for AD9746, only the typical values found in Table 2. 

Regards,
Marco

Thanks for the quick reply. To clarify, when you say the AD9746 is inherently monotonic, does that apply to the AD9747 was well? Since the DNL for that is spec'd at 2.0 LSB I would assume that means it isn't monotonic, but I'd like to clarify. 

Thanks,

Yes, all the generics in this device family are monotonic. Typical High-speed CMOS devices like this use a current-steering DAC architecture (2 differential outputs IOUTP and IOUTN), which makes the DAC by design inherently monotonic. The ±2.0 LSB DNL for AD9747 does not cause non-monotonicity, it just means less optimal linearity values. The DAC will be non-monotonic if the DNL is less than –1 LSB at any transition (i.e. its transfer characteristic contains one or more localized maxima or minima). 

Regards,

Marco

Yes, all the generics in this device family are monotonic. Typical High-speed CMOS devices like this use a current-steering DAC architecture (2 differential outputs IOUTP and IOUTN), which makes the DAC by design inherently monotonic. The ±2.0 LSB DNL for AD9747 does not cause non-monotonicity, it just means less optimal linearity values. The DAC will be non-monotonic if the DNL is less than –1 LSB at any transition (i.e. its transfer characteristic contains one or more localized maxima or minima). 

Regards,

Marco