8.2.2.2.1 Method 1
The saturation current should be greater than the sum of the maximum load current and the worst case average to peak inductor current. Use Equation 2 to find the saturation current (ISAT).
Equation 2. I
SAT > I
OUT_MAX + I
RIPPLEwhere
- IOUT_MAX is the maximum load current (750 mA).
- IRIPPLE is the average-to-peak inductor current. Use Equation 3 to calculate the IRIPPLE value.
Equation 3. where
- VIN is the maximum input voltage in application.
- VOUT is the output voltage
- L is the minimum inductor value including worst-case tolerances (30% drop can be considered for Method 1)
- f is the minimum switching frequency (5.7 MHz)