Question
The instrument level device we are designing would require a DAC with very high
S/N -ratio. I was unable to find a clear answer to what this is in AD1139 from
the data sheets. Theoretically it should be something of the order of 110 dB
but what in practice? The SFDR-level would be of interest too (actually more
than SNR). We'd also like to know the difference between AD1139J and -K models.
Can you provide this DAC on circuit board with output SMA-connector?
Answer
The AD1139 is designed for DC level setting applications, therefore only the Dc
specs are included on the datasheet. The INL and DNL are great on the AD1139.
At DC yes the SNR is 110dB
SNR and SFDR are AC specs and the AD1139 is not designed or tested for it’s
ability to reconstruct sinewaves accurately. Settling time and transition
glitches will reduce the SNR at any frequency above DC. It’s just not tested on
the AD1139.