Datasheet

ELECTRICAL CHARACTERISTICS (referto the test circuit, T
J
=25°C, V
i
= 35V, R
4
= 30KΩ,
C
9
= 2.7nF, f
SW
= 100KHztyp, unlessotherwise specified)
DYNAMIC CHARACTERISTICS
Symbol Parameter Test Conditions Min. Typ. Max. Unit Fig.
V
i
Input Volt. Range (pin 11) V
o
=V
ref
to 40V
I
o
=2A(**)
15 50 V 5
V
o
Output Voltage V
i
=15V to 50V
I
o
= 1A;V
o
=V
ref
5 5.1 5.2 V 5
∆V
o
Line Regulation V
i
= 15V to 50V
I
o
= 0.5A; V
o
=V
ref
12 30 mV
∆V
o
Load Regulation Vo =V
ref
I
o
= 0.5A to 2A 7 20 mV
V
d
Dropout Voltage between
Pin 11 and 20
I
o
= 2A 0.25 0.4 V
I
20L
Max Limiting Current V
i
= 15V to 50V
V
o
=V
ref
to 40V
2.5 2.8 3.5 A
η Efficiency (*) I
o
= 2A,f = 100KHz
V
o
=V
ref
V
o
= 12V
75 85
90
%
%
SVR Supply Voltage Ripple
Rejection
V
i
= 2VRMS; I
o
=1A
f = 100Hz; V
o
=V
ref
56 60 dB 5
f Switching Frequency 90 100 110 KHz 5
∆f/∆Vi Voltage Stability of
Switching
Frequency
V
i
= 15V to 45V 2 6 % 5
∆f/T
j
Temperature Stability of
Switching Frequency
T
j
= 0 to 125°C1%5
f
max
Maximum Operating
Switching Frequency
V
o
=V
ref
R
4
=15KΩ
I
o
=2AC
9
= 2.2nF
200 KHz 5
(*) Only for DIP version (**) Pulse testing with a low duty cycle
V
ref
SECTION(pin 13)
Symbol Parameter Test Condition Min. Typ. Max. Unit Fig.
V
13
Reference Voltage 5 5.1 5.2 V 7
∆V
13
Line Regulation V
i
= 15V to 50V 10 25 mV 7
∆V
13
Load Regulation I13 = 0 to 1mA 20 40 mV 7
∆ V
13
∆T
Average Temperature
Coefficient Reference
Voltage
T
j
=0°C to 125°C 0.4 mV/°C7
I
13 short
Short Circuit Current Limit V
13
= 0 70 mA 7
V
START
SECTION (pin 15)
Symbol Parameter Test Condition Min. Typ. Max. Unit Fig.
V
14
Reference Voltage 11.4 12 12.6 V 7
∆V
14
Line Regulation V
i
= 15 to 50V 0.6 1.4 V 7
∆V
14
Load Regulation I14 = 0 to 1mA 50 200 mV 7
I
14 short
Short Circuit Current Limit V15 =0V 80 mA 7
L4972A-L4972AD
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