8.2.2 Detailed Design Procedure

The first step in the design procedure is to verify that the maximum possible output current of the boost converter supports the specific application requirements. A simple approach is to estimate the converter efficiency, by taking the efficiency numbers from the provided efficiency curves or to use a worst-case assumption for the expected efficiency, for example, 90%.

1. Duty cycle:
Equation 1.
2. Maximum output current:
Equation 2.
3. Peak switch current:
Equation 3.
where
• 
• I_swpeak = converter switch current (minimum switch current limit = 2 A)
• fs = Converter switching frequency (typically 1.2 MHz)
• L = Selected inductor value
• η = Estimated converter efficiency (please use the number from the efficiency plots or 90% as an estimation)
• ΔI_L = Inductor peak-to-peak ripple current

The peak switch current is the steady-state peak switch current that the integrated switch, inductor, and external Schottky diode must be able to handle. The calculation must be done for the minimum input voltage where the peak switch current is the highest.