LM2578A/LM3578A
Absolute Maximum Ratings
ESD Tolerance (Note 4)
2 kV
If Military/Aerospace specified devices are required,
please contact the National Semiconductor Sales Office/
Distributors for availability and specifications.
Total Supply Voltage
Collector Output to Ground
Emitter Output to Ground (Note 2)
Power Dissipation (Note 3)
Output Current
Storage Temperature
Lead Temperature
(soldering, 10 seconds)
Maximum Junction Temperature
260˚C
150˚C
50V
−0.3V to +50V
−1V to +50V
Internally limited
750 mA
−65˚C to +150˚C
Operating Ratings
Ambient Temperature Range
LM2578A
LM3578A
Junction Temperature Range
LM2578A
LM3578A
−40˚C
≤
T
J
≤+125˚C
0˚C
≤
T
J
≤+125˚C
−40˚C
≤
T
A
≤+85˚C
0˚C
≤
T
A
≤+70˚C
Electrical Characteristics
These specifications apply for 2V
≤
V
IN
≤
40V (2.2V
≤
V
IN
≤
40V for T
J
≤
−25˚C), timing capacitor C
T
= 3900 pF, and 25%
≤
duty cycle
≤
75%, unless otherwise specified. Values in standard typeface are for T
J
= 25˚C; values in
boldface type
apply for
operation over the specified operating junction temperature range.
LM2578A/
Symbol
OSCILLATOR
f
OSC
Frequency
20
24
16
∆f
OSC
/∆T
Frequency Drift with Temperature
Amplitude
REFERENCE/COMPARATOR
V
R
Input Reference
Voltage
∆V
R
/∆V
IN
Input Reference Voltage Line
Regulation
Inverting Input Current
Level Shift Accuracy
∆V
R
/∆t
OUTPUT
V
C
(sat)
V
E
(sat)
I
CES
BV
CEO(SUS)
Collector Saturation Voltage
Emitter Saturation Voltage
Collector Leakage Current
I
C
= 750 mA pulsed, Emitter
grounded
I
O
= 80 mA pulsed,
V
IN
= V
C
= 40V
V
IN
= V
CE
= 40V, Emitter grounded,
Output OFF
0.1
200/250
60
50
CURRENT LIMIT
V
CL
Sense Voltage Shutdown Level
Referred to V
IN
or Ground
110
80
160
mV
mV (min)
mV (max)
0.7
0.90/1.2
1.4
1.7/2.0
V
V (max)
V
V (max)
µA
µA (max)
V
V (min)
Input Reference Voltage Long Term
Stability
I
1
= I
2
= 0 mA and
I
1
= I
2
= 1 mA
±
1% (Note 8)
I
1
= I
2
= 0 mA and
I
1
= I
2
= 1 mA
±
1% (Note 8)
I
INV
I
1
= I
2
= 0 mA, duty cycle = 25%
Level Shift Current = 1 mA
0.5
1.0
10/13
100
0.003
0.01/0.02
1.0
1.050/1.070
0.950/0.930
V
V (max)
V (min)
%/V
%/V (max)
µA
%
% (max)
ppm/1000h
−0.13
550
kHz
kHz (max)
kHz (min)
%/˚C
mV
p-p
Parameter
Conditions
Typical
LM3578A
Limit
Units
Collector-Emitter Sustaining Voltage I
SUST
= 0.2A (pulsed), V
IN
= 0
3
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