Datasheet LM1117MPX-5.0, LM1117T-ADJ, LM1117T-5.0, LM1117T-3.3, LM1117T-2.85 Datasheet (NSC)

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LM1117 800mA Low-Dropout Linear Regulator

General Description

The LM1117 is a series of low dropout voltage regulators with a dropout of 1.2V at 800mA of load current. It has the same pin-out as National Semiconductor’s industry standard LM317.

The LM1117 is available in an adjustable version, which can set the output voltage from 1.25V to 13.8V with only two external resistors. In addition, it is also available in five fixed voltages, 1.8V, 2.5V, 2.85V, 3.3V, and 5V.

The LM1117 offers current limiting and thermal shutdown. Its circuit includes a zener trimmed bandgap reference to assure output voltage accuracy to within

1%.

The LM1117 series is available in SOT-223, TO-220, and TO-252 D-PAK packages. A minimum of 10µF tantalum capacitor is required at the output to improve the transient response and stability.

Features

n Available in 1.8V, 2.5V, 2.85V, 3.3V, 5V, and Adjustable

Versions

n Space Saving SOT-223 Package n Current Limiting and Thermal Protection n Output Current 800mA n Temperature Range 0˚C to 125˚C n Line Regulation 0.2%(Max) n Load Regulation 0.4%(Max)

Applications

n 2.85V Model for SCSI-2 Active Termination n Post Regulator for Switching DC/DC Converter n High Efficiency Linear Regulators n Battery Charger n Battery Powered Instrumentation

Typical Application

Active Terminator for SCSI-2 Bus

DS100919-5

Fixed Output Regulator

DS100919-28

February 2000

LM1117 800mA Low-Dropout Linear Regulator

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Ordering Information

Package

Temperature Range

Packaging Marking Transport Media NSC Drawing

0˚C to +125˚C

3-lead SOT-223 LM1117MPX-ADJ N03A Tape and Reel MA04A

LM1117MPX-1.8 N12A Tape and Reel

* LM1117MPX-2.5 N13A Tape and Reel

LM1117MPX-2.85 N04A Tape and Reel

LM1117MPX-3.3 N05A Tape and Reel LM1117MPX-5.0 N06A Tape and Reel

3-lead TO-220 LM1117T-ADJ LM1117T-ADJ Rails T03B

LM1117T-2.85 LM1117T-2.85 Rails

LM1117T-3.3 LM1117T-3.3 Rails LM1117T-5.0 LM1117T-5.0 Rails

3-lead TO-252 LM1117DTX-ADJ LM1117DT-ADJ Tape and Reel TD03B

LM1117DTX-1.8 LM1117DT-1.8 Tape and Reel

* LM1117DTX-2.5 LM1117DT-2.5 Tape and Reel

LM1117DTX-2.85 LM1117DT-2.85 Tape and Reel

LM1117DTX-3.3 LM1117DT-3.3 Tape and Reel LM1117DTX-5.0 LM1117DT-5.0 Tape and Reel

Note:*Contact factory for availability.

Block Diagram

DS100919-1

LM1117

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Connection Diagrams

SOT-223

DS100919-4

Top View

TO-220

DS100919-2

Top View

TO-252

DS100919-38

Top View

LM1117

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Absolute Maximum Ratings (Note 1)

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

Maximum Input Voltage (V

to GND)

LM1117-ADJ, LM1117-1.8, LM1117-2.5, LM1117-3.3, LM1117-5.0 20V

Power Dissipation (Note 2) Internally Limited Junction Temperature (T

)

(Note 2)

150˚C

Storage Temperature Range -65˚C to 150˚C Lead Temperature

TO-220 (T) Package 260˚C, 10 sec SOT-223 (IMP) Package 260˚C, 4 sec ESD Tolerance (Note 3) 2000V

Operating Ratings (Note 1)

Input Voltage (V

to GND)

LM1117-ADJ, LM1117-1.8, LM1117-2.5, LM1117-3.3, LM1117-5.0

15V

LM1117-2.85 10V Junction Temperature Range

)(Note 2)

0˚C to 125˚C

Electrical Characteristics

Typicals and limits appearing in normal type apply for TJ= 25˚C. Limits appearing in Boldface type apply over the entire junction temperature range for operation, 0˚C to 125˚C.

Symbol Parameter Conditions

Min

(Note 5)

Typ

(Note 4)

Max

(Note 5)

Units

REF

Reference Voltage LM1117-ADJ

OUT

= 10mA, VIN-V

OUT

= 2V, TJ= 25˚C

10mA ≤ I

OUT

≤ 800mA, 1.4V ≤ VIN-V

OUT

≤ 10V

1.238

1.225

1.250

1.262

1.270

V V

OUT

Output Voltage LM1117-1.8

OUT

= 10mA, VIN= 3.8V, TJ= 25˚C

0 ≤ I

OUT

≤ 800mA, 3.2V ≤ VIN≤ 10V

1.782

1.746

1.800

1.818

1.854

V V

LM1117-2.5 I

OUT

= 10mA, VIN= 4.5V, TJ= 25˚C

0 ≤ I

OUT

≤ 800mA, 3.9V ≤ VIN≤ 10V

2.475

2.450

2.500

2.525

2.550

V V

LM1117-2.85 I

OUT

= 10mA, VIN= 4.85V, TJ= 25˚C

0 ≤ I

OUT

≤ 800mA, 4.25V ≤ VIN≤ 10V

0 ≤ I

OUT

≤ 500mA, VIN= 4.10V

2.820

2.790

2.850

2.880

2.910

V V V

LM1117-3.3 I

OUT

= 10mA, VIN=5VTJ= 25˚C

0 ≤ I

OUT

≤ 800mA, 4.75V≤ VIN≤ 10V

3.267

3.235

3.300

3.333

3.365

V V

LM1117-5.0 I

OUT

= 10mA, VIN= 7V, TJ= 25˚C

0 ≤ I

OUT

≤ 800mA, 6.5V ≤ VIN≤ 12V

4.950

4.900

5.000

5.050

5.100

V V

∆V

OUT

Line Regulation (Note 6)

LM1117-ADJ I

OUT

= 10mA, 1.5V ≤ VIN-V

OUT

≤

13.75V

0.035 0.2

LM1117-1.8 I

OUT

= 0mA, 3.2V ≤ VIN≤ 10V

1 6 mV

LM1117-2.5 I

OUT

= 0mA, 3.9V ≤ VIN≤ 10V

1 6 mV

LM1117-2.85 I

OUT

= 0mA, 4.25V ≤ VIN≤ 10V 1 6 mV

LM1117-3.3 I

OUT

= 0mA, 4.75V ≤ VIN≤ 15V 1 6 mV

LM1117-5.0 I

OUT

= 0mA, 6.5V ≤ VIN≤ 15V 1 10 mV

LM1117

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Electrical Characteristics (Continued)

Typicals and limits appearing in normal type apply for TJ= 25˚C. Limits appearing in Boldface type apply over the entire junction temperature range for operation, 0˚C to 125˚C.

Symbol Parameter Conditions

Min

(Note 5)

Typ

(Note 4)

Max

(Note 5)

Units

∆V

OUT

Load Regulation (Note 6)

LM1117-ADJ V

IN-VOUT

= 3V, 10 ≤ I

OUT

≤ 800mA 0.2 0.4

LM1117-1.8 V

= 3.2V, 0 ≤ I

OUT

≤ 800mA

1 10 mV

LM1117-2.5 V

= 3.9V, 0 ≤ I

OUT

≤ 800mA

1 10 mV

LM1117-2.85 V

= 4.25V, 0 ≤ I

OUT

≤ 800mA 1 10 mV

LM1117-3.3 V

= 4.75V, 0 ≤ I

OUT

≤ 800mA 1 10 mV

LM1117-5.0 V

= 6.5V, 0 ≤ I

OUT

≤ 800mA 1 15 mV

IN-VOUT

Dropout Voltage (Note 7)

OUT

= 100mA 1.10 1.20 V

OUT

= 500mA 1.15 1.25 V

OUT

= 800mA 1.20 1.30 V

LIMIT

Current Limit VIN-V

OUT

= 5V, TJ= 25˚C 800 1200 1500 mA

Minimum Load Current (Note 8)

LM1117-ADJ V

= 15V 1.7 5 mA

Quiescent Current LM1117-1.8

≤ 15V

5 10 mA

LM1117-2.5 V

≤ 15V

5 10 mA

LM1117-2.85 V

≤ 10V 5 10 mA

LM1117-3.3 V

≤ 15V 5 10 mA

LM1117-5.0 V

≤ 15V 5 10 mA

Thermal Regulation T

= 25˚C, 30ms Pulse 0.01 0.1

Ripple Regulation f

RIPPLE

=1 20Hz, VIN-V

OUT

=3V

RIPPLE

=1V

60 75 dB

Adjust Pin Current 60 120 µA Adjust Pin Current

Change

10 ≤ I

OUT

≤ 800mA,

1.4V ≤ V

IN-VOUT

≤ 10V 0.2 5 µA

Temperature Stability 0.5

Long Term Stability T

= 125˚C, 1000Hrs 0.3

RMS Output Noise (%of V

OUT

), 10Hz ≤ f ≤10kHz 0.003

Thermal Resistance Junction-to-Case

3-Lead SOT-223 3-Lead TO-220 3-Lead TO-252

15.0

3.0 10

˚C/W ˚C/W ˚C/W

Thermal Resistance Junction-to-Ambient (No heat sink; No air flow)

3-Lead SOT-223 3-Lead TO-220 3-Lead TO-252 (Note 9)

136

79 92

˚C/W ˚C/W ˚C/W

Note 1: Absolute Maximum Ratings indicatelimits beyond which damage to the device may occur. Operating Ratings indicate conditions for which the device is intended to be functional, but specific performance is not guaranteed. For guaranteed specifications and the test conditions, see the Electrical Characteristics.

Note 2: The maximum power dissipation is a function of T

J(max)

, θJA, and TA. The maximum allowable power dissipation at any ambient temperature is

=(T

J(max)–TA

)/θJA. All numbers apply for packages soldered directly into a PC board.

Note 3: For testing purposes, ESD was applied using human body model, 1.5kΩ in series with 100pF. Note 4: Typical Values represent the most likely parametric norm. Note 5: All limits are guaranteed by testing or statistical analysis. Note 6: Load and line regulation are measured at constant junction room temperature.

LM1117

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Electrical Characteristics (Continued)

Note 7: The dropout voltage is the input/output differential at which the circuit ceases to regulate against further reduction in input voltage. It is measured when the

output voltage has dropped 100mV from the nominal value obtained at V

IN=VOUT

+1.5V.

Note 8: The minimum output current required to maintain regulation. Note 9: Minimum pad size of 0.038in

LM1117

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Typical Performance Characteristics

Dropout Voltage (VIN-V

OUT

)

DS100919-22

Short-Circuit Current

DS100919-23

Load Regulation

DS100919-24

LM1117-ADJ Ripple Rejection

DS100919-6

LM1117-ADJ Ripple Rejection vs. Current

DS100919-7

Temperature Stability

DS100919-25

LM1117

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Typical Performance Characteristics (Continued)

Adjust Pin Current

DS100919-26

LM1117-2.85 Load Transient Response

DS100919-8

LM1117-5.0 Load Transient Response

DS100919-9

LM1117-2.85 Line Transient Response

DS100919-10

LM1117-5.0 Line Transient Response

DS100919-11

LM1117

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APPLICATION NOTE

1.0 External Capacitors/Stability

1.1 Input Bypass Capacitor

An input capacitor is recommended. A10µF tantalum on the input is a suitable input bypassing for almost all applications.

1.2 Adjust Terminal Bypass Capacitor

The adjust terminal can be bypassed to ground with a bypass capacitor (C

ADJ

) to improve ripple rejection. This bypass capacitor prevents ripple from being amplified as the output voltage is increased. At any ripple frequency, the impedance of the C

ADJ

should be less than R1 to prevent the

ripple from being amplified:

(2π*f

RIPPLE*CADJ

)<R1

The R1 is the resistor between the output and the adjust pin. Its value is normally in the range of 100-200Ω. For example, with R1=124Ω and f

RIPPLE

=120Hz, the C

ADJ

should be

11µF.

1.3 Output Capacitor

The output capacitor iscriticalin maintaining regulator stability, and must meet the required conditions for both minimum amount of capacitance and ESR (Equivalent Series Resistance). The minimum output capacitance required by the LM1117 is 10µF, ifatantalum capacitor is used.Any increase of the output capacitance will merely improve the loop stability and transient response. The ESR of the output capacitor should be less than 0.5Ω. In the case of the adjustable regulator, when the C

ADJ

is used, a larger output capacitance

(22µf tantalum) is required.

2.0 Output Voltage

The LM1117 adjustable version develops a 1.25V reference voltage, V

REF

, between the output and the adjust terminal.

As shown in

Figure 1

, this voltage is applied across resistor R1 to generate a constant current I1. The current I

ADJ

from the adjust terminal could introduce error to the output. But since it is very small (60µA) compared with the I1 and very constant with line and load changes, the error can be ignored. The constant current I1 then flows through the output set resistor R2 and sets the output voltage to the desired level.

For fixed voltage devices, R1 and R2 are integrated inside the devices.

3.0 Load Regulation

The LM1117 regulates the voltage that appears between its output and ground pins, or between its output and adjust pins. In some cases, line resistances can introduce errors to the voltage across the load. To obtain the best load regulation, a few precautions are needed.

Figure 2

, shows a typical application using a fixed output regulator. The Rt1 and Rt2 are the line resistances. It is obvious that the V

LOAD

is less than the V

OUT

by the sum of the voltage drops along the line resistances. In this case, the load regulation seen at the R

LOAD

would be degraded from the data sheet specification. To improve this, the load should be tied directly totheoutputterminal on the positive side and directly tied to the ground terminal on the negative side.

When the adjustable regulator is used (

Figure 3

), the best performance is obtained with the positive side of the resistor R1 tied directly to the output terminal of the regulator rather than near theload.This eliminates line drops from appearing effectively in series with the reference and degrading regulation. For example, a 5V regulator with 0.05Ω resistance between the regulator and load will have a load regulation due to line resistance of 0.05Ω xI

. If R1 (=125Ω) is connected near the load, the effective line resistance will be 0.05Ω (1+R2/R1) or in this case, it is 4 times worse. In addition, the ground side of the resistor R2 can be returned near the ground of the load toprovideremoteground sensing and improve load regulation.

4.0 Protection Diodes

Under normal operation, the LM1117 regulators do not need any protection diode. With the adjustable device, the internal resistance between the adjust andoutputterminalslimits the current. No diode is needed to divert the current around the regulator even with capacitor on the adjust terminal. The adjust pin can take a transient signal of

25V with respect to

the output voltage without damaging the device. When a output capacitor is connected to a regulator and the

input is shortedtoground, the output capacitor will discharge

DS100919-17

FIGURE 1. Basic Adjustable Regulator

DS100919-18

FIGURE 2. Typical Application using Fixed Output

Regulator

DS100919-19

FIGURE 3. Best Load Regulation using Adjustable

Output Regulator

LM1117

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APPLICATION NOTE (Continued)

into the output of the regulator. The discharge current depends on the value of the capacitor, the output voltage of the regulator, and rate of decrease of V

. In the LM1117 regulators, the internal diode between the output and input pins can withstand microsecond surge currents of 10A to 20A. With an extremely large output capacitor (≥1000 µF), and with input instantaneously shorted to ground, the regulator could be damaged.

In this case, an external diode is recommended between the output and input pins to protect the regulator, as shown in

Figure 4

5.0 Heatsink Requirements

When an integrated circuit operates with an appreciable current, its junction temperature is elevated. It is important to quantify its thermal limits in order to achieve acceptable performance and reliability.Thislimit is determined by summing the individual parts consisting of a series of temperature rises from the semiconductor junction to the operating environment. A one-dimensional steady-state model of conduction heat transfer is demonstrated in

Figure 5

. The heat generated at the device junction flows through the die to the die attach pad, through the lead frame to the surrounding case material, to the printed circuit board, and eventually to the ambient environment. Below isalist of variables that may affect the thermal resistance and in turn the need for a heatsink.

θJC

(Component Vari-

ables)

θCA

(Application Vari-

ables)

Leadframe Size & Material

Mounting Pad Size, Material, & Location

No. of Conduction Pins Placement of Mounting

Pad Die Size PCB Size & Material Die Attach Material Traces Length & Width Molding Compound Size

and Material

Adjacent Heat Sources

Volume of Air

Ambient Temperatue

Shape of Mounting Pad

The LM1117 regulators have internal thermal shutdown to protect the device from over-heating. Under all possible operating conditions, the junction temperature of the LM1117 must be within the range of 0˚C to 125˚C. A heatsink may be required depending on the maximum power dissipation and maximum ambient temperature of the application. To determine if a heatsink is needed, the power dissipated by the regulator, P

, must be calculated:

IN=IL+IG

PD=(VIN-V

OUT)IL+VINIG

Figure 6

shows the voltages and currents which are present

in the circuit.

DS100919-15

FIGURE 4. Regulator with Protection Diode

DS100919-37

FIGURE 5. Cross-sectional view of Integrated Circuit

Mounted on a printed circuit board. Note that the case

temperature is measured at the point where the leads

contact with the mounting pad surface

DS100919-16

FIGURE 6. Power Dissipation Diagram

LM1117

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APPLICATION NOTE (Continued)

The next parameter which must be calculated is the maximum allowable temperature rise, T

(max):

(max)=TJ(max)-TA(max)

where T

(max) is the maximum allowable junction tempera-

ture (125˚C), and T

(max) is the maximum ambient tem-

perature which will be encountered in the application. Using the calculated values for T

(max) and PD, the maximum allowable value for the junction-to-ambient thermal resistance (θ

) can be calculated:

JA=TR

(max)/P

If the maximum allowable value for θJAis found to be ≥136˚C/W for SOT-223 package or ≥79˚C/W for TO-220 package or ≥92˚C/W for TO-252 package, no heatsink is

needed since the package alone will dissipate enough heat to satisfy these requirements. If the calculated value for θ

falls below these limits, a heatsink is required. As a design aid,

Table 1

shows the value of the θJAof SOT223 and TO-252 for different heatsink area. The copper patterns that we used to measure these θ

s are shown at the

end of the Application Notes Section.

Figure 7

and

Figure 8

reflects the same test results as what are in the

Table 1

Figure 9

and

Figure 10

shows themaximumallowable power dissipation vs. ambient temperature for the SOT-223 and TO-252 device. Figures

Figure 11

and

Figure 12

shows the

maximum allowable power dissipation vs. copper area (in

) for the SOT-223 and TO-252 devices. Please see AN1028 for power enhancementtechniques to be used with SOT-223 and TO-252 packages.

TABLE 1. θ

Different Heatsink Area

Layout Copper Area Thermal Resistance

Top Side (in

)* Bottom Side (in2)(θ

,˚C/W) SOT-223 (θJA,˚C/W) TO-252 1 0.0123 0 136 103 2 0.066 0 123 87 3 0.3 0 84 60 4 0.53 0 75 54 5 0.76 0 69 52 61 0 66 47 7 0 0.2 115 84 8 0 0.4 98 70 9 0 0.6 89 63

10 0 0.8 82 57 11 0 1 79 57 12 0.066 0.066 125 89 13 0.175 0.175 93 72 14 0.284 0.284 83 61 15 0.392 0.392 75 55 16 0.5 0.5 70 53

*Tab of device attached to topside copper

LM1117

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APPLICATION NOTE (Continued)

DS100919-13

FIGURE 7. θJAvs. 1oz Copper Area for SOT-223

DS100919-34

FIGURE 8. θJAvs. 2oz Copper Area for TO-252

DS100919-12

FIGURE 9. Maximum Allowable Power Dissipation vs.

Ambient Temperature for SOT-223

DS100919-36

FIGURE 10. Maximum Allowable Power Dissipation vs.

Ambient Temperature for TO-252

DS100919-14

FIGURE 11. Maximum Allowable Power Dissipation vs.

1oz Copper Area for SOT-223

DS100919-35

FIGURE 12. Maximum Allowable Power Dissipation vs.

2oz Copper Area for TO-252

LM1117

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APPLICATION NOTE (Continued)

DS100919-20

FIGURE 13. Top View of the Thermal Test Pattern in Actual Scale

LM1117

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APPLICATION NOTE (Continued)

DS100919-21

FIGURE 14. Bottom View of the Thermal Test Pattern in Actual Scale

LM1117

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Typical Application Circuits

DS100919-30

Adjusting Output of Fixed Regulators

DS100919-31

Regulator with Reference

DS100919-29

1.25V to 10V Adjustable Regulator with Improved Ripple Rejection

DS100919-27

5V Logic Regulator with Electronic Shutdown*

DS100919-32

Battery Backed-Up Regulated Supply

LM1117

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Typical Application Circuits (Continued)

DS100919-33

Low Dropout Negative Supply

LM1117

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Physical Dimensions inches (millimeters) unless otherwise noted

3-Lead SOT-223 Package

Order Number LM1117MPX-ADJ, LM1117MPX-1.8, LM1117MPX-2.5, LM1117MPX-2.85, LM1117MPX-3.3, or

LM1117MPX-5.0

NSC Package Number MA04A

LM1117

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Physical Dimensions inches (millimeters) unless otherwise noted (Continued)

3-Lead TO-220 Package

Order Number LM1117T-ADJ, LM1117T-2.85, LM1117T-3.3, or LM1117T-5.0

NSC Package Number T03B

LM1117

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Physical Dimensions inches (millimeters) unless otherwise noted (Continued)

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NATIONAL’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT AND GENERAL COUNSEL OF NATIONAL SEMICONDUCTOR CORPORATION. As used herein:

1. Life support devices or systems are devices or systems which, (a) are intended for surgical implant into the body, or (b) support or sustain life, and whose failure to perform when properly used in accordance with instructions for use provided in the labeling, can be reasonably expected to result in a significant injury to the user.

2. A critical component is any component of a life support device or system whose failure to perform can be reasonably expected to cause the failure of the life support device or system, or to affect its safety or effectiveness.

National Semiconductor Corporation

Americas Tel: 1-800-272-9959 Fax: 1-800-737-7018 Email: support@nsc.com

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Fax: +49 (0) 180-530 85 86

Email: europe.support@nsc.com Deutsch Tel: +49 (0) 69 9508 6208 English Tel: +44 (0) 870 24 0 2171 Français Tel: +33 (0) 1 41 91 8790

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Tel: 81-3-5639-7560 Fax: 81-3-5639-7507

www.national.com

3-Lead TO-252 Package

Order Number LM1117DTX-ADJ, LM1117DTX-1.8, LM1117DTX-2.5, LM1117DTX-2.85, LM1117DTX-3.3, or LM1117DTX-5.0

NSC Package Number TD03B

LM1117 800mA Low-Dropout Linear Regulator

National does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and National reserves the right at any time without notice to change said circuitry and specifications.