Datasheet

Symbol Parameter Test Conditions Min. Typ. Max. Unit
DYNAMIC CHARACTERISTICS
V
o
Output voltage range V
i
= 46V I
o
=1A V
ref
40 V
V
i
Input voltage range V
o
=V
ref
to 36V I
o
= 1.5A 9 46 V
∆ V
o
Line regulation V
i
= 10V to 40V V
o
=V
ref
I
o
=1A 15 50 mV
∆V
o
Load regulation V
o
=V
ref
I
o
= 0.5A to 1.5A 8 20 mV
V
ref
Internal reference voltage
(pin 10)
V
i
= 9V to 46V I
o
= 1A 5 5.1 5.2 V
∆
V
ref
∆ T
Average temperature
coefficient of refer. voltage
T
j
=0°C to 125°C
I
o
=1A
0.4 mV/°C
V
d
Dropout voltage I
o
= 1.5A 1.5 2 V
I
om
Maximum operating load
current
V
i
= 9V to 46V
V
o
=V
ref
to 36V
1.5 A
I
2L
Current limiting threshold
(pin 2)
V
i
= 9V to 46V
V
o
=V
ref
to 36V
2 3.3 A
I
SH
Input average current V
i
= 46V; output short-circuit 15 30 mA
η Efficiency f = 100KHz V
o
=V
ref
70 %
I
o
=1A V
o
= 12V 80 %
SVR Supply voltage ripple
rejection
∆ V
i
=2V
rms
fripple
= 100Hz
V
o
=V
ref
Io = 1A
50 56 dB
ELECTRICAL CHARACTERISTICS (Refer to the test circuit, T
j
=25°C, V
i
= 35V, unless otherwise
specified)
HEPTAWATT POWERDIP NAME
FUNCTION
4 4, 5, 12, 13 GROUND Common ground terminal.
5 14 OSCILLATOR A parallel RC network connected to this terminal
determines the switching frequency. This pin must be
connected to pin 7 input when the internal oscillator is
used.
6 15 SOFT START Soft start time constant. A capacitor is connected
between this terminal and ground to define the soft start
time constant. This capacitor also determines the
average short circuit output current.
7 2 OUTPUT Regulator output.
1, 3, 6,
8, 9, 16
N.C.
PIN FUNCTIONS (cont’d)
3/15
L4962