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Design >> Analog Design >> Bandgap voltage reference for 16b audio DAC
https://designers-guide.org/forum/YaBB.pl?num=1185250887

Message started by hyy95 on Jul 23^rd, 2007, 9:21pm

Title: Bandgap voltage reference for 16b audio DAC
Post by hyy95 on Jul 23^rd, 2007, 9:21pm

Hi,
is high precision bandgap voltage reference a must for 16b audio DAC with SNR>100dB?
if the answer is yes, how much precision do we need? e.g. What 's the TC range? How much PSRR do we need?

what about the voltage reference for 9b current steering DAC?

Thanks!
Jerry

Title: Re: Bandgap voltage reference for 16b audio DAC
Post by jp314159 on Aug 2^nd, 2007, 1:04pm

No, it is not usually necessary -- the reference is basically a multiplier on the DAC digital code -- so for audio applications, it is like a volume control. No one will notice even a 5% change in audio volume.

On the other hand, you _DO_ want a low-noise reference -- else you will add distortion and (strange) noise to your output. You are going to want noise and PSRR better than your DAC to avoid degrading it.

Depending on the application, the 9-bit DAC likely does need a 9-bit (e.g. 0.1%) reference.