L4973D3 STMICROELECTRONICS [STMicroelectronics], L4973D3 Datasheet - Page 12

• Manufacturer Part Number: L4973D3
• Description: 3.5A STEP DOWN SWITCHING REGULATOR
• Manufacturer: STMICROELECTRONICS [STMicroelectronics]

L4973V3.3 - L4973V5.1 - L4973D3.3 - L4973D5.1
Figure 28: Source Current Rise and Fall Time,
Figure 30:Soft Start Capacitor Selection vs. In-
12/16
Figure 32: 3.5A at V
Lomax
( H)
150
100
50
0
15
V
CC
pin 2, 3 (See fig1)
ductor and V
20
f
sw
C1
= 200KHz
25
R2
C2
30
O
< 3.3V (see part list fig. 1)
CC
C7
C3
35
max (ref. AN938)
C5
40
45
1
17
7,8
11
R1
C6
D97IN654
50
L4973V3.3
INH
10
D97IN666A
Vi(V)
16
C4
SYNC
R5
18
13,14,15
4,5,6
Figure 29: Soft Start Capacitor Selection vs.
Figure 31: Open Loop Frequency and Phase of
2,3
12
9
GAIN
Lomax
-100
-150
-200
(dB)
-50
50
( H)
300
250
200
150
100
0
50
0
10
25
D1
C8
10
Inductor and V
Error amplifier
2
30
L1
1.5
2.5
3 x
C0
V
10
1
2
3
P
f
sw
3
= 100KHz
3.6K
4.7K
7.5K
5.1K
10
2K
R
35
5
4
10
4.7K
3.6K
3.6K
R
2K
1K
Vo
R3
CC
5
3
40
10
max (ref. AN938)
V
6
O
Phase
Css=1 F
=3.36-1.74
GAIN
10
45
7
10
D97IN663
Css=220nF
Css=470nF
Css=100nF
Css=820nF
Css=680nF
50
8
R
R
D97IN653
3
5
f(Hz)
Phase
Vi(V)
135
45
90
0