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L6997

3.9 Soft start capacitor

Considering the soft start equations:

The equations are valid without load. When an active load is present the equations result more complex; further

some active loads have unexpected effect, as higher current than the expected one during the soft start, can

change the start up time.

In this case the capacitor value can be selected on the application; anyway the Eq11 gives an idea about the

3.10 Sink mode

Figure 13. Efficiency vs output current

0,0

10,0

20,0

30,0

40,0

50,0

60,0

70,0

80,0

90,0

100,0

0,01,0

2,03,0

4,05,0

Current [A]

Eff [%]