Absolute Maximum Ratings (Note 1)

If Military/Aerospace specified devices are required,

please contact the National Semiconductor Sales Office/

Distributors for availability and specifications.

Total Supply Voltage

50V

Collector Output to Ground

−0.3V to +50V

Emitter Output to Ground (Note 2)

−1V to +50V

Power Dissipation (Note 3)

Internally limited

Output Current

750 mA

Storage Temperature

−65˚C to +150˚C

Lead Temperature

(soldering, 10 seconds)

260˚C

Maximum Junction Temperature

150˚C

ESD Tolerance (Note 4)

2 kV

Operating Ratings

Ambient Temperature Range

LM2578A

−40˚C

≤ T

A

≤+85˚C

LM3578A

0˚C

≤ T

A

≤+70˚C

Junction Temperature Range

LM2578A

−40˚C

≤ T

J

≤+125˚C

LM3578A

0˚C

≤ T

J

≤+125˚C

Electrical Characteristics

These specifications apply for 2V

≤ V

IN

≤ 40V (2.2V ≤ V

IN

≤ 40V for T

J

≤ −25˚C), timing capacitor C

≤

duty cycle

≤ 75%, unless otherwise specified. Values in standard typeface are for T

operation over the specified operating junction temperature range.

LM2578A/

Symbol

Parameter

Conditions

Typical

LM3578A

Units

(Note 5)

Limit (Note 6)

OSCILLATOR

f

OSC

Frequency

20

kHz

24

kHz (max)

16

kHz (min)

∆f

∆T

Frequency Drift with Temperature

−0.13

%/˚C

Amplitude

550

mV

p-p

REFERENCE/COMPARATOR (Note 7)

V

R

Input Reference

I

1.0

V

Voltage

I

1.050/1.070

V (max)

0.950/0.930

V (min)

∆V

∆V

IN

Input Reference Voltage Line

Regulation

I

0.003

%/V

I

0.01/0.02

%/V (max)

I

INV

Inverting Input Current

I

0.5

µA

Level Shift Accuracy

Level Shift Current=1mA

1.0

%

10/13

% (max)

∆V

∆t

Input Reference Voltage Long Term

Stability

100

ppm/1000h

OUTPUT

V

Collector Saturation Voltage

I

grounded

0.7

V

0.90/1.2

V (max)

V

Emitter Saturation Voltage

I

1.4

V

V

1.7/2.0

V (max)

I

CES

Collector Leakage Current

V

Output OFF

0.1

µA

200/250

µA (max)

BV

CEO(SUS)

Collector-Emitter Sustaining Voltage I

60

V

50

V (min)

CURRENT LIMIT

V

CL

Sense Voltage Shutdown Level

Referred to V

110

mV

(Note 9)

80

mV (min)

160

mV (max)

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