NSC LM7815CT, LM7815CK, LM7812CT Datasheet

LM78XX
Series Voltage Regulators

LM78XX Series Voltage Regulators

May 2000

General Description

The LM78XX series of three terminal regulators is available
with several fixed output voltages making them useful in a
wide range of applications. One of these is local on card
regulation, eliminating the distribution problems associated
with single point regulation. The voltages available allow
these regulators to be used in logic systems, instrumenta­tion, HiFi, and other solid state electronic equipment. Al­though designed primarily as fixed voltage regulators these
devices can be used with external components to obtain ad­justable voltages and currents.

The LM78XX series is available in an aluminum TO-3 pack­age which will allow over 1.0A load current if adequate heat
sinking is provided. Current limiting is included to limit the
peak output current to a safe value. Safe area protection for
the output transistor is provided to limit internal power dissi­pation. If internal power dissipation becomes too high for the
heat sinking provided, the thermal shutdown circuit takes
over preventing the IC from overheating.

Considerable effort was expanded to make the LM78XX se­ries of regulators easy to use and minimize the number of
external components. It is not necessary to bypass the out-

Connection Diagrams

Metal Can Package

TO-3 (K)

Aluminum

put, although this does improve transient response. Input by­passing is needed only if the regulator is located far from the
filter capacitor of the power supply.

For output voltage other than 5V, 12V and 15V the LM117
series provides an output voltage range from 1.2V to 57V.

Features

n Output current in excess of 1A
n Internal thermal overload protection
n No external components required
n Output transistor safe area protection
n Internal short circuit current limit
n Available in the aluminum TO-3 package

Voltage Range

LM7805C 5V
LM7812C 12V
LM7815C 15V

Plastic Package

TO-220 (T)

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Bottom View

Order Number LM7805CK,

LM7812CK or LM7815CK

See NS Package Number KC02A

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Order Number LM7805CT,

LM7812CT or LM7815CT

See NS Package Number T03B

Top View

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Schematic

LM78XX

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LM78XX

Absolute Maximum Ratings (Note 3)

If Military/Aerospace specified devices are required,
please contact the National Semiconductor Sales Office/
Distributors for availability and specifications.

Input Voltage

(V

= 5V, 12V and 15V) 35V

O

Internal Power Dissipation (Note 1) Internally Limited
Operating Temperature Range (T

) 0˚C to +70˚C

A

Maximum Junction Temperature

(K Package) 150˚C
(T Package) 150˚C

Storage Temperature Range −65˚C to +150˚C

Lead Temperature (Soldering, 10 sec.)

TO-3 Package K 300˚C
TO-220 Package T 230˚C

Electrical Characteristics LM78XXC (Note 2)

0˚C ≤ TJ≤ 125˚C unless otherwise noted.

Output Voltage 5V 12V 15V

Input Voltage (unless otherwise noted) 10V 19V 23V Units

Symbol Parameter Conditions Min Typ Max Min Typ Max Min Typ Max

V

∆V

∆V

I

Q

∆I

V

O

Q

N

Output Voltage Tj = 25˚C, 5 mA ≤ IO≤ 1A 4.8 5 5.2 11.5 12 12.5 14.4 15 15.6 V

P

≤ 15W, 5 mA ≤ IO≤ 1A 4.75 5.25 11.4 12.6 14.25 15.75 V

D

V

≤ VIN≤ V

MIN

Line Regulation IO= 500mATj = 25˚C 3 50 4 120 4 150 mV

O

∆V

MAX

IN

(7.5 ≤ VIN≤ 20) (14.5 ≤ VIN≤

27)

(17.5 ≤ VIN≤

30)

(7 ≤ VIN≤ 25) 14.5 ≤ VIN≤ 30) (17.5 ≤ VIN≤

30)
0˚C ≤ Tj ≤ +125˚C 50 120 150 mV
∆V

IN

(8 ≤ VIN≤ 20) (15 ≤ VIN≤ 27) (18.5 ≤ VIN≤

30)

I

≤ 1A Tj = 25˚C 50 120 150 mV

O

∆V

IN

(7.5 ≤ VIN≤ 20) (14.6 ≤ VIN≤

27)

(17.7 ≤ VIN≤

30)
0˚C ≤ Tj ≤ +125˚C 25 60 75 mV
∆V

IN

Load Regulation Tj = 25˚C 5 mA ≤ IO≤ 1.5A 10 50 12 120 12 150 mV

O

250 mA ≤ I

≤

O

(8 ≤ VIN≤ 12) (16 ≤ VIN≤ 22) (20 ≤ VIN≤ 26) V

25 60 75 mV

750 mA

5mA≤I

≤1A, 0˚C ≤ Tj ≤

O

50 120 150 mV

+125˚C

Quiescent Current IO≤ 1A Tj = 25˚C 8 8 8 mA

0˚C ≤ Tj ≤ +125˚C 8.5 8.5 8.5 mA

Quiescent Current 5 mA ≤ IO≤ 1A 0.5 0.5 0.5 mA
Change Tj = 25˚C, I

V

≤ VIN≤ V

MIN

≤ 1A 1.0 1.0 1.0 mA

O

MAX

(7.5 ≤ VIN≤ 20) (14.8 ≤ VIN≤ 27) (17.9 ≤ VIN≤

30)

I

≤ 500 mA, 0˚C ≤ Tj ≤ +125˚C 1.0 1.0 1.0 mA

O

V

MIN

≤ VIN≤ V

MAX

(7 ≤ VIN≤ 25) (14.5 ≤ VIN≤ 30) (17.5 ≤ VIN≤

30)

Output Noise

TA=25˚C, 10 Hz ≤ f ≤ 100 kHz 40 75 90 µV

Voltage

Ripple Rejection IO≤ 1A, Tj = 25˚Cor62 80 55 72 54 70 dB

V

V

V

V

V

V

f = 120 Hz I

≤ 500 mA 62 55 54 dB

O

0˚C ≤ Tj ≤ +125˚C

V

MIN

≤ VIN≤ V

MAX

(8 ≤ VIN≤ 18) (15 ≤ VIN≤ 25) (18.5 ≤ VIN≤

V

28.5)

R

O

Dropout Voltage Tj = 25˚C, I

= 1A 2.0 2.0 2.0 V

OUT

Output Resistance f = 1 kHz 8 18 19 mΩ

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