SLVSHX6 December 2024 TPS62966 , TPS62968
PRODUCTION DATA
Most low-noise and low-ripple applications use a ferrite bead and bypass capacitor before the load. Using a second L-C filter is especially useful for low-noise and low-ripple applications with constant load current such as ADCs, DACs, and Jitter Cleaner. The second stage L-C filter is optional, and the device can be used without this filter. Without the filter, the device has a low output voltage noise of typically 16.9μVRMS with an output voltage ripple of 280μVRMS . The second stage L-C filter attenuates the output voltage ripple by another approximately 30dB. To improve load regulation, the device can remote sense the output voltage after the second stage L-C filter and is internally compensated for the additional double pole generated by the L-C filter.
To keep the second stage L-C filter as small as possible, the internal compensation is optimized for a 10nH to 50nH inductance. A small ferrite bead or even a PCB trace provides sufficient inductance for output voltage ripple filtering. For details, see Section 7.2.2.2.4.