On another closed thread, SgtWookie wrote:
Is that 120 microvolts of noise enough that I should forget about the cap across IN and COMMON, and just put one each on the op amp's V+ and V-? Are they going to make much of a difference with respect to noise at that level?
I wonder if this is true in the particular case of a dual rail op amp being powered by a TLE2426 rail splitter which isn't powering anything else. If I have a bypass cap across the TLE2426 IN and COMMON, that "stiffens" the voltage into the TLE. From there, I assume that I can depend on the TLE to reliably divide that stable difference into halves (or as close to halves as that particular TLE can manage), without introducing significant new noise. If I'm reading the data sheet correctly, the noise out of the TLE2426 is about 120 microvolts, since I'm using the three lead version which has no noise reduction pin.If the IC has a dual-rail supply (eg: Vcc/Vdd, GND, and Vee/Vss) then you need at least two caps; one from GND to Vcc/Vdd and one from GND to Vee/Vss.
Is that 120 microvolts of noise enough that I should forget about the cap across IN and COMMON, and just put one each on the op amp's V+ and V-? Are they going to make much of a difference with respect to noise at that level?