L4973 STMicroelectronics, L4973 Datasheet - Page 11

• Manufacturer Part Number: L4973
• Description: 3.5A STEP DOWN SWITCHING REGULATOR
• Manufacturer: STMicroelectronics

Figure 22: Efficiency vs. Output Current
Figure 24: Power dissipation vs. Output Voltage
Figure 26: Load Transient
Pdiss
2
1
(%)
(A)
90
85
80
75
70
I
(W)
3.0
2.5
2.0
1.5
1.0
0.5
3
2
1
O
0
0
0
0.5
(Device only)
200 s/DIV
Vcc=12V
5
(see fig.1d)
V
f
sw
T
CC
T
1
= 100KHz
= 35V
10
1.5
Vcc=24V
15
Vcc=48V
2
20
2.5
V
f
sw
CC
= 100KHz
V
f
sw
= 35V
O
25
= 200KHz
= 3.3V
3
D97IN649
I
I
I
O
O
I
30
O
I
D97IN662
3.5
D97IN648
O
O
=3.5A
=2.5A
=2A
=1A
=3A
V
I
O
(mV)
-100
O
100
V
(A)
(V)
0
O
Figure 23: Power dissipation vs. Input Voltage
Figure 25: Pulse by Pulse Limiting Current vs.
Figure 27: Line Transient
L4973V3 - L4973V5 - L4973D3 - L4973D5
V
Pdiss
Ilim
1
2
(A)
5.2
4.8
4.6
4.4
4.2
(V)
30
20
10
(W)
5
1.5
1.0
0.5
CC
0
-40 -20
0
(Device only) (see fig.1c)
Junction Temperature
1ms/DIV
10
0
20 40
I
O
=2.5A
20
I
O
=3A
I
O
I
O
=3.5A
30
60 80
=2A
Vcc=35
I
f
O
sw
40
= 1A
= 100KHz
100
V
f
sw
O
= 100KHz
= 5.1V
120
D97IN650
50
D97IN647A
D97IN652
Vcc(V)
Tj( C)
(mV)
-100
100
V
0
11/16
O