I need a ultra low noise power supply with power and sequence control. Can i use a LTC2973 with two LT3045 ultra low noise LDO for this?
Yes, Just as long as EN/UV voltage of LT3045 reaches/exceeds 1.24V (EN/UV pin threshold:Rising) or higher to turn it ON.And according to specs of LTC2972 Vout_en is capable of up to 15V. So I think there will be no problem using that combination.
thanks for your answer. My next question is: How can build the current monitor and voltage fine adjustment without decrease the performance by LT3045 (Noise, PSRR)?
With best regards
You can refer to the "Applications information" section of the datasheet. There you can find how to improve LT3045 perfomance in reference to noise and PSRR.