Absolute Maximum Ratings (Note 1)
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.
Operating Ratings
Ambient Temperature Range
LM1578A
Total Supply Voltage
50V
−0.3V to +50V
−1V to +50V
−55˚C ≤ TA ≤+125˚C
−40˚C ≤ TA ≤+85˚C
0˚C ≤ TA ≤+70˚C
Collector Output to Ground
Emitter Output to Ground (Note 2)
Power Dissipation (Note 3)
Output Current
LM2578A
LM3578A
Internally limited
750 mA
Junction Temperature Range
LM1578A
−55˚C ≤ TJ ≤+150˚C
−40˚C ≤ TJ ≤+125˚C
0˚C ≤ TJ ≤+125˚C
Storage Temperature
−65˚C to +150˚C
LM2578A
Lead Temperature
LM3578A
(soldering, 10 seconds)
Maximum Junction Temperature
260˚C
150˚C
Electrical Characteristics
=
These specifications apply for 2V ≤ VIN ≤ 40V (2.2V ≤ VIN ≤ 40V for TJ ≤ −25˚C), timing capacitor CT 3900 pF, and 25% ≤
=
duty cycle ≤ 75%, unless otherwise specified. Values in standard typeface are for TJ 25˚C; values in boldface type apply for
operation over the specified operating junction temperature range.
LM1578A
Limit
LM2578A/
LM3578A
Symbol
Parameter
Conditions
Typical
Units
(Note 5)
(Note 6)
(Note 11)
Limit
(Note 7)
OSCILLATOR
fOSC
Frequency
20
kHz
22.4
17.6
24
16
kHz (max)
kHz (min)
%/˚C
∆fOSC/∆T
Frequency Drift with
Temperature
−0.13
550
Amplitude
mVp-p
REFERENCE/COMPARATOR (Note 8)
=
=
VR
Input Reference
Voltage
I1 I2 0 mA and
1.0
V
=
=
±
I1 I2 1 mA 1% (Note 9)
1.035/1.050 1.050/1.070 V (max)
0.965/0.950 0.950/0.930 V (min)
%/V
=
=
∆VR/∆VIN
Input Reference Volt-
age Line Regulation
Inverting Input
I1 I2 0 mA and
0.003
0.5
=
=
±
I1 I2 1 mA 1% (Note 9)
0.01/0.02
0.01/0.02 %/V (max)
=
=
=
IINV
I1 I2 0 mA, duty cycle 25%
µA
Current
=
Level Shift Accuracy
Level Shift Current 1 mA
1.0
%
5/8
10/13
% (max)
∆VR/∆t
Input Reference
Voltage Long Term
Stability
100
ppm/1000h
OUTPUT
=
VC (sat)
Collector Saturation
Voltage
IC 750 mA pulsed, Emitter
0.7
1.4
0.1
60
V
grounded
0.85/1.2
1.6/2.1
50/100
50
0.90/1.2
1.7/2.0
200/250
50
V (max)
V
=
IO 80 mA pulsed,
VE (sat)
ICES
Emitter Saturation
Voltage
=
=
VIN VC 40V
V (max)
µA
=
=
Collector Leakage
Current
VIN VCE 40V, Emitter
grounded, Output OFF
µA (max)
V
=
=
0
BVCEO(SUS) Collector-Emitter
Sustaining Voltage
ISUST 0.2A (pulsed), VIN
V (min)
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