Explanation: The silicon steel EI butt stack exhibits high permeability high flux density and ease of construction and mounting therefore, it is most commonly used in low voltage switching regulators. 13. Find the value of Rsc, L and Co for a µA7840 switching regulator to provide +5 v at 3A, using the following specifications: toff= 24µs, ripple voltage = 400mA and ton=26µs.
A. Rsc = 55 mΩ , L = 25µH & Co = 750µF
B. Rsc = 550 mΩ , L = 25µH & Co = 75µF
C. Rsc = 650 mΩ , L = 25µH & Co = 65µF
D. Rsc = 720 mΩ , L = 25µH & Co = 250µF
Answer:A
Explanation: The silicon steel EI butt stack exhibits high permeability high flux density and ease of construction and mounting therefore, it is most commonly used in low voltage switching regulators. 13. Find the value of Rsc, L and Co for a µA7840 switching regulator to provide +5 v at 3A, using the following specifications: toff= 24µs, ripple voltage = 400mA and ton=26µs.
A. Rsc = 55 mΩ , L = 25µH & Co = 750µF B. Rsc = 550 mΩ , L = 25µH & Co = 75µF C. Rsc = 650 mΩ , L = 25µH & Co = 65µF D. Rsc = 720 mΩ , L = 25µH & Co = 250µF
Explanation: Peak current,Ipk= 400mA× 1.5 (since Ipk = 1.5 A for peak current)