JAJSNJ1H May 2013 – December 2021 TPS65310A-Q1
PRODUCTION DATA
The inductor value L depends on the allowed ripple current ΔIL_PP in the coil at chosen input voltage VIN and output voltage VOUT, and given switching frequency fsw:
For example:
VIN = 3.3 V (from BUCK1)
VOUT = 5 V
ΔIL_PP = 200 mA (20% of 1-A peak current)
ƒsw = 0.98 MHz
→ L ≈ 4.7 μH
The capacitor value COUT
must be selected such that the L-C double-pole frequency FLC is in the
range of
10 kHz–15 kHz. The FLC is given
by Equation 12:
The right half-plane zero FRHPZ, as given in Equation 13, must be > 200 kHz:
where
If the condition FRHPZ > 200 kHz is not satisfied, L and therefore COUT have to be recalculated.