Electrical characteristics
L4973
4
Electrical characteristics
Table 4. Electrical characteristics
(Refer to the test circuit,V
CC
= 24V; T
J
= 25°C, C
OSC
= 2.7nF; R
OSC
= 20KΩ;
unless otherwise specified)
Symbol
Parameter
Test condition
Min
Typ
Max
Unit
Dynamic characteristics
Input Voltage Range
(1)
Output Voltage
L4973V5.1
V
O
= V
REF
to 40V; I
O
= 3.5A
I
O
= 1A
I
O
= 0.5A to 3.5A V
CC
= 8V
to 55V
I
O
= 1A
Output Voltage
L4973V3.3
I
O
= 0.5A to 3.5A V
CC
= 8V
to 40V
V
CC
= 10.5V I
O
= 3.5A
(2)
8
5.05
5.00
5.1
5.1
5.1
3.36
3.36
3.36
0.15
55
5.15
5.20
5.25
3.393
3.427
3.46
0.22
0.35
V
V
V
V
V
V
V
Ω
Ω
A
A
%
%
(2)
4.95
3.326
3.292
(2)
3.26
R
DS(on )
Maximum Limiting
Current
η
(2)
(2)
V
CC
= 8V to 55V
V
O
= 5.1V; I
O
= 3.5A
V
O
= 3.3V; I
O
= 3.5A
3.8
4
4.5
4.5
90
85
5.5
5.5
Efficiency
Switching Frequency
Supply Voltage Ripple
Rejection
(2)
90
60
100
110
KHz
dB
V
i
= V
CC
+2V
RMS
V
O
= V
ref
;
I
O
= 1A; f
ripple
= 100Hz
V
CC
= 8V to 55V
∆f
sw
Switching Frequency
Stability vs., Supply
Voltage
2
5
%
Reference section
Reference Voltage
I
ref
= 0 to 20mA;
V
CC
= 8 to 55V
I
ref
= 0mA;
V
CC
= 8 to 55V
V
ref
= 0 to 5mA;
V
CC
= 0 to 20mA
30
5.025
(2)
5.1
5.1
5
2
6
65
5.175
5.250
10
10
25
100
V
V
mV
mV
mV
mA
4.950
Line Regulation
Load Regulation
Short Circuit Current
6/27
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