E-L4971D013TR Datasheet, PDF (9/13 Pages) STMicroelectronics – 1.5A STEP DOWN SWITCHING REGULATOR

Figure 24. Load transient.
Figure 25. Line transient.
V_CC
(V)
30
20
10
1
2
1ms/DIV
D97IN786
I_O = 1A
f_sw = 100KHz
V_O
(mV)
100
0
-100
Figure 26. Soft start capacitor selection Vs
inductor and Vccmax.
L
(µH)
400
300
fsw=100KHz
680nF
D97IN745
470nF
330nF
200
220nF
100
100nF
0
15 20 25 30 35 40 45 50 V_CCmax(V)
L4971
Figure 27. Soft start capacitor selection vs.
Inductor and Vccmax
L
(µH)
fsw=200KHz
D97IN746
56nF
300
47nF
200
33nF
22nF
100
0
15 20 25 30 35 40 45 50 V_CCmax(V)
Figure 28. Open loop frequency and phase of
error amplifier
GAIN
(dB)
50
0
-50
D97IN787
Phase
GAIN
0
45
-100
-150
Phase
90
135
-200
10 10² 10³ 10⁴ 10⁵ 10⁶ 10⁷ 10⁸ f(Hz)
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