SC4524B_08 Datasheet, PDF (15/18 Pages) Semtech Corporation – 18V 2A Step-Down Switching Regulator

SC4524B
Recommended Component Parameters in Typical Applications
Table 4 lists the recommended inductance (L₁) and compensation network (R₇, C₅, C₈) for common input and output
voltages. The inductance is determined by assuming that the ripple current is 35% of load current I_O. The compensator
parameters are calculated by assuming a 22mF low ESR ceramic output capacitor and a loop gain crossover frequency
of F_SW/10.
Table 4. Recommended inductance (L₁) and compensator (R₇, C₅, C₈)
Typical Applications
Recommended Parameters
Vin(V) Vo(V)
Io(A) Fsw(kHz) C2(uF) L1(uH) R7(k) C5(nF) C8(pF)
1.5
1
500
1000
3.3
2
500
1000
1
500
2.5
2
1000
500
1000
6.8
6.65
2.2
3.3
12.4
0.68
3.3
6.65
2.2
1.5
12.4
0.68
4.7
22.1
0.68
2.2
35.7
0.47
2.2
18.2
0.68
1.5
35.7
0.47
1.5
1
2
500
1000
500
1000
6.8
6.65
2.2
3.3
12.7
0.68
3.3
6.65
2.2
2.2
12.7
0.68
5
2.5
1
500
1000
2
500
1000
8.2
11.3
1.5
4.7
23.7
0.47
4.7
11.3
1
2.2
20
0.47
1
500
3.3
2
1000
500
1000
6.8
15
0.82
3.3
26.7
0.47
3.3
15
0.82
2.2
29.4
0.47
1.5
1
2
500
500
22
8.2
7.15
2.2
4.7
7.15
2.2
10
1
500
2.5
2
1000
500
1000
15
11.3
1
6.8
20
0.68
6.8
11.3
1
3.3
20
0.47
3.3
1
2
500
1000
500
1000
15
15
0.82
8.2
30.9
0.47
8.2
15
0.82
4.7
30.9
0.47
12
5
1
500
1000
2
500
1000
15
23.7
0.68
10
41.2
0.47
8.2
23.7
0.68
4.7
45.3
0.47
1
500
7.5
2
1000
500
1000
15
35.7
0.68
8.2
63.4
0.47
8.2
35.7
0.68
4.7
63.4
0.47
10
1
500
1000
2
500
1000
10
42.2
0.68
4.7
84.5
0.47
4.7
42.2
0.68
2.2
84.5
0.47
15