Which LDO is suitable for ADXL354?

Question

Hello everyone~ I have an ADXL354 and I am designing a low noise circuit. May I ask if I should use 3.3VLDO to supply VCC of ADXL354 or 1.8VLDO to supply V1P8ANA of ADXL354? Last question, can you recommend a low noise external LDO for ADXL354? my power supply is 5V I am using ADR4550 as reference voltage. 
 Thanks for your replies.

ahan · Accepted Answer

ADR4550 is fine. any LDO or reference with low-noise is fine. 
 For the best performance, you can use LTC6655)

ahan · Answer

use a 1.8V voltage reference to power the V1P8ANA is better, but I don't think the difference is big. 
 More importantly, I think choosing an ADC with the same reference as V1P8ANA is better.

ahan · Answer

I checked with our design team. Here is their answer: 
 &ldquo;&hellip; the sensor and front-end amplifier are the dominant noise sources. The signal path is fully differential, and the ADC and signal path are all ratiometric to the supply. Applying a low-noise external supply will not improve the noise below the performance with the internal regulated supply.&rdquo; 
 
 So in simple terms, makes no difference if you use an external LDO in terms of noise.

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Which LDO is suitable for ADXL354?