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LM78XX/LM78XXA — 3-Terminal 1A Positive Voltage Regulator

September 2011

LM78XX/LM78XXA 3-Terminal 1A Positive Voltage Regulator
Features
• • • • • Output Current up to 1A Output Voltages of 5, 6, 8, 9, 10, 12, 15, 18, 24 Thermal Overload Protection Short Circuit Protection Output Transistor Safe Operating Area Protection

General Description
The LM78XX series of three terminalpositive regulators are available in the TO-220 package and with several fixed output voltages, making them useful in a wide range of applications. Each type employs internal current limiting, thermal shut down and safe operating area protection, making it essentially indestructible. If adequate heat sinking is provided, they can deliver over 1A output current. Although designed primarily as fixedvoltage regulators, these devices can be used with external components to obtain adjustable voltages and currents.

Ordering Information
Product Number
LM7805CT LM7806CT LM7808CT LM7809CT LM7810CT LM7812CT LM7815CT LM7818CT LM7824CT LM7805ACT LM7806ACT LM7808ACT LM7809ACT LM7810ACT LM7812ACT LM7815ACT LM7818ACT LM7824ACT ±2% 0°C to +125°C

Output Voltage Tolerance
±4%

Package
TO-220 (SingleGauge)

Operating Temperature
-40°C to +125°C

© 2011 Fairchild Semiconductor Corporation LM78XX/LM78XXA Rev. 1.1 1

www.fairchildsemi.com

LM78XX/LM78XXA 3-Terminal 1A Positive Voltage Regulator

Block Diagram
Input 1 Current Generator SOA Protection Series Pass Element Output 3

Starting Circuit

Reference Voltage

Error Amplifier

Thermal Protection GND 2

Figure 1.

PinAssignment
TO-220 (Single Gauge)
GND

1

1. Input 2. GND 3. Output

Figure 2.

Absolute Maximum Ratings
Absolute maximum ratings are those values beyond which damage to the device may occur. The datasheet specifications should be met, without exception, to ensure that the system design is reliable over its power supply, temperature, and output/input loading variables. Fairchild does notrecommend operation outside datasheet specifications.

Symbol
VI RθJC RθJA TOPR TSTG Input Voltage

Parameter
VO = 5V to 18V VO = 24V Thermal Resistance Junction-Cases (TO-220) Thermal Resistance Junction-Air (TO-220) Operating Temperature Range Storage Temperature Range LM78xx LM78xxA

Value
35 40 5 65 -40 to +125 0 to +125 -65 to +150

Unit
V V °C/W °C/W °C

°C

2www.fairchildsemi.com

LM78XX/LM78XXA Rev. 1.1

LM78XX/LM78XXA 3-Terminal 1A Positive Voltage Regulator

Electrical Characteristics (LM7805)
Refer to the test circuits. -40°C < TJ < 125°C, IO = 500mA, VI = 10V, CI = 0.1µF, unless otherwise specified.

Symbol
VO

Parameter
Output Voltage TJ = +25°C

Conditions
5mA ≤ IO ≤ 1A, PO ≤ 15W, VI = 7V to 20V

Min.
4.8 4.75 – – – – – – – – – 62.0 – –– –

Typ.
5.0 5.0 4.0 1.6 9.0 4.0 5.0 0.03 0.3 -0.8 42.0 73.0 2.0 15.0 230 2.2

Max.
5.2 5.25 100 50.0 100 50.0 8.0 0.5 1.3 – – – – – – –

Unit
V

Regline

Line Regulation(1) Regulation(1)

TJ = +25°C TJ = +25°C TJ = +25°C

VO = 7V to 25V VI = 8V to 12V IO = 5mA to 1.5A IO = 250mA to 750mA

mV

Regload Load

mV

IQ ∆IQ ∆VO/∆T VN RR VDROP rO ISC IPK

Quiescent Current

mAmA

Quiescent Current Change IO = 5mA to 1A VI = 7V to 25V Output Voltage Drift(2) IO = 5mA f = 10Hz to 100kHz, TA = +25°C f = 120Hz, VO = 8V to 18V IO = 1A, TJ = +25°C f = 1kHz VI = 35V, TA = +25°C TJ = +25°C Output Noise Voltage Ripple Rejection(2) Resistance(2)
(2)

mV/°C µV/VO dB V mΩ mA A

Dropout Voltage Output

Short Circuit Current Peak Current

Notes: 1. Load and lineregulation are specified at constant junction temperature. Changes in VO due to heating effects must be taken into account separately. Pulse testing with low duty is used. 2. These parameters, although guaranteed, are not 100% tested in production.

3 LM78XX/LM78XXA Rev. 1.1

www.fairchildsemi.com

LM78XX/LM78XXA 3-Terminal 1A Positive Voltage Regulator

Electrical Characteristics (LM7806)...
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