SWCS133D September 2015 – May 2019 TPS65094
PRODUCTION DATA.
An inductor must be placed between the external FETs and the output capacitors. Together, the inductor and output capacitors form a double-pole in the control loop that contributes to stability. In addition, the inductor is responsible for the output ripple, efficiency, and transient performance. When the inductance increases, the ripple current decreases, which typically results in an increase in efficiency. However, with an increase in inductance, the transient performance decreases. Finally, the inductor selected must be rated for appropriate saturation current, core losses, and DCR.
NOTE
Internal parameters for the converters are optimized for a 0.47-µH inductor; however, it is possible to use other inductor values as long as they are chosen carefully and thoroughly tested.
Equation 3 shows the calculation for the recommended inductance for the converter.
where
With the chosen inductance value and the peak current for the inductor in steady state operation, IL(MAX) can be calculated using Equation 4. The rated saturation current of the inductor must be higher than the IL(MAX) current.
Following these equations, Table 7-2 lists the preferred inductor selected for the converters.
MANUFACTURER | PART NUMBER | VALUE | SIZE | HEIGHT |
---|---|---|---|---|
Cyntec | PIFE32251B-R47MS | 0.47 µH | 3.2 mm × 2.5 mm | 1.2 mm |