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

LM1578A

−55˚C

≤ T

LM2578A

−40˚C

≤ T

LM3578A

0˚C

≤ T

Junction Temperature Range

LM1578A

−55˚C

≤ T

LM2578A

−40˚C

≤ T

LM3578A

0˚C

≤ T

Electrical Characteristics

These specifications apply for 2V

≤ V

duty cycle

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

operation over the specified operating junction temperature range.

LM1578A

LM2578A/

Symbol

Parameter

Conditions

Typical

Limit

LM3578A

Units

(Note 5)

(Note 6)

(Note 11)

Limit

(Note 7)

OSCILLATOR

f

OSC

Frequency

20

kHz

22.4

24

kHz (max)

17.6

16

kHz (min)

∆f

Frequency Drift with

−0.13

%/˚C

Temperature

Amplitude

550

mV

p-p

REFERENCE/COMPARATOR (Note 8)

V

R

Input Reference

I

1.0

V

Voltage

I

1.035/1.050

1.050/1.070 V (max)

0.965/0.950

0.950/0.930

V (min)

∆V

Input Reference Volt-

I

0.003

%/V

age Line Regulation

I

0.01/0.02

0.01/0.02

%/V (max)

I

INV

Inverting Input

I

0.5

µA

Current

Level Shift Accuracy

Level Shift Current = 1 mA

1.0

%

5/8

10/13

% (max)

∆V

Input Reference

100

ppm/1000h

Voltage Long Term

Stability

OUTPUT

V

Collector Saturation

I

0.7

V

Voltage

grounded

0.85/1.2

0.90/1.2

V (max)

V

Emitter Saturation

I

1.4

V

Voltage

V

1.6/2.1

1.7/2.0

V (max)

I

CES

Collector Leakage

V

0.1

µA

Current

grounded, Output OFF

50/100

200/250

µA (max)

BV

CEO(SUS)

Collector-Emitter

I

V

Sustaining Voltage

50

50

V (min)

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