INCREASING THE CURRENT LIMIT THRESHOLD

The current limit threshold is nominally 1.25A, with a mini-

mum guaranteed value of 1.0A. If, at maximum load current,

the lower peak of the inductor current (I

exceeds 1.0A, resistor R

and I

exceed that lower peak current. This resistor diverts some of

the recirculating current from the internal sense resistor so

that a higher current level is needed to switch the internal

current limit comparator. I

(11)

where I

the minimum ripple current calculated using Equation 10.

R

20119934

FIGURE 15. Efficiency vs V

IN

Circuit of Figure 14

20119935

FIGURE 16. Efficiency vs Load Current and V

IN

Circuit of Figure 14

20119936

FIGURE 17. Output Voltage Ripple vs V

IN

Circuit of Figure 14

20119937

FIGURE 18. Frequency vs V

IN

Circuit of Figure 14

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