Question ten

For a 12-V input, 1.0 V output, 4 MHz, 25-A buck converter, the designer wants to get the best performance and minimum loss on the low side (Sync) FET. The controller has a minimum dead time of 25 ns. dI_L = 4 A. Calculate the Sync FET losses for a EPC2023 with a Schottky diode in parallel with a V_f = 0.4 V. (Hint: From the EPC2023 data sheet, V_DS = 30 V, R_DS(on)max = 1.3 m Ω, I_D=25 A, Q_rr = 0.0, V_SD(30A) = 2.2 V, cycle time = (1/4 MHz) T = 250 ns; T_Deadtime = 2 x 25 ns = 50 ns
A. 0.58 W
B. 3.5 W
C. 4.58 W
D. 2.0 W
E. 2.58 W

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