L4974 STMicroelectronics, L4974 Datasheet - Page 10

• Manufacturer Part Number: L4974
• Description: 3.5A SWITCHING REGULATOR
• Manufacturer: STMicroelectronics

L4974A
Figure 6a : Component Layout of fig.5 (1 : 1 scale). Evaluation Board Available
PART LIST
R
R
R
R
R
R
R
R
R
** C
* 2 capacitors in parallel to increase input RMS current capability.
* * 3 capacitors in parallel to reduce total output ESR.
10/22
* C
1
2
3
4
5
6
7
8
9
C
C
C
C
C
C
C
D1 = SB 560 (OR EQUIVALENT)
L1 = 150 H
core 58310 MAGNETICS
45 TURNS 0.91mm (AWG 19)
COGEMA 949181
= 30K
= 10K
= 15K
= 30K
= 22
= 4.7K
= see table A
= OPTION
= 4.7K
1
3
7
8
9
10
11
12
15
= C
= 390pF Film
= 22nF MKT 1837 (ERO)
= C
= 2.7nF KP 1830 (ERO)
= 0.33 F Film
= 1nF
= C
= 1 F Film
4
2
13
= C
= 1000 F 63V EYF (ROE)
= C
5
= C
14
= 100 F 40V EKR (ROE)
6
= 2,2 F 50V
Table A
Table B
SUGGESTED BOOSTRAP CAPACITORS
Operatin g F requency
12V
15V
18V
24V
V
f = 100KHz
f = 200KHz
f = 500KHz
f = 20KHz
f = 50KHz
0
4.7k
4.7k
4.7k
4.7k
R
9
Boo strap Cap.c10
680nF
470nF
330nF
220nF
100nF
6.2kW
9.1k
12
18
R
7