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LM337L
SNVS780E – MAY 1998 – REVISED DECEMBER 2016
LM337L 3-Terminal Adjustable Regulator
1 Features
•
•
•
•
•
•
•
•
•
1
Adjustable Output Down to 1.2 V
Ensured 100-mA Output Current
Line Regulation Typically 0.01%/V
Load Regulation Typically 0.1%
Current Limit Constant With Temperature
Eliminates the Need to Stock Many Voltages
Standard 3-Pin Transistor Package
80-dB Ripple Rejection
Output is Short Circuit Protected
2 Applications
•
•
•
•
•
•
•
•
Normally, only a single 1-µF solid tantalum output
capacitor is required unless the device is situated
more than 6 inches from the input filter capacitors, in
which case an input bypass is required. A larger
output capacitor can be added to improve transient
response. The adjustment pin can be bypassed to
achieve very high ripple rejection ratios, which are
difficult to achieve with standard 3-pin regulators.
Besides replacing fixed regulators, the LM337L is
useful in a wide variety of other applications. Because
the regulator is floating and monitors only the inputto-output differential voltage, supplies of several
hundred volts can be regulated as long as the
maximum input-to-output differential is not exceeded.
The LM337L makes a simple adjustable switching
regulator, a programmable output regulator, or by
connecting a fixed resistor between the adjustment
and output, the LM337L can be used as a precision
current regulator. Supplies with electronic shutdown
can be achieved by clamping the adjustment pin to
ground, which programs the output to 1.2 V, where
most loads draw little current.
Industrial Power Supplies
Factory Automation Systems
Building Automation Systems
PLC Systems
Instrumentation
IGBT Drive Negative Gate Supplies
Networking
Set-Top Boxes
The LM337L is available in a standard TO-92
transistor package and a standard SO-8 surface
mount package. The LM337L is rated for operation
over a –25°C to 125°C range.
3 Description
The LM337L is an adjustable 3-pin negative voltage
regulator capable of supplying 100 mA over a –1.2-V
to –37-V output range. The LM337L is easy to use
and requires only two external resistors to set the
output voltage. Both line and load regulation are
better than standard fixed regulators. The LM337L is
packaged in a standard, easy-to-use TO-92 transistor
package.
In addition to higher performance than fixed
regulators, the LM337L offers full overload protection.
Included on the chip are current limit, thermal
overload protection, and safe area protection. All
overload protection circuitry remains fully functional
even if the adjustment pin is disconnected.
For applications requiring output current in excess of
0.5 A and 1.5 A, The LM137 series may be suitable.
For the positive complement, the LM117 and LM317L
series are options.
Device Information(1)
PART NUMBER
LM337L
PACKAGE
BODY SIZE (NOM)
SOIC (8)
3.91 mm × 4.90 mm
TO-92 (3)
4.30 mm × 4.30 mm
(1) For all available packages, see the orderable addendum at
the end of the data sheet.
1.2-V to 25-V Adjustable Regulator
LM337L Available Packages
Pin 1. Output
2. Adjustment
3. Input
R2
+
C2
ADJ
-VIN
VIN
LM337L
VOUT
R1
240 Ÿ
3
1
+
C1
1 µF
2
SOIC
TO-92
1
Copyright © 2016, Texas Instruments Incorporated
1
An IMPORTANT NOTICE at the end of this data sheet addresses availability, warranty, changes, use in safety-critical applications,
intellectual property matters and other important disclaimers. PRODUCTION DATA.
LM337L
SNVS780E – MAY 1998 – REVISED DECEMBER 2016
www.ti.com
Table of Contents
1
2
3
4
5
6
7
Features ..................................................................
Applications ...........................................................
Description .............................................................
Revision History.....................................................
Pin Configuration and Functions .........................
Specifications.........................................................
1
1
1
2
3
3
6.1
6.2
6.3
6.4
6.5
6.6
3
3
3
4
4
5
Absolute Maximum Ratings ......................................
ESD Ratings..............................................................
Recommended Operating Conditions.......................
Thermal Information ..................................................
Electrical Characteristics...........................................
Typical Characteristics ..............................................
Detailed Description .............................................. 6
7.1 Overview ................................................................... 6
7.2 Functional Block Diagram ......................................... 6
7.3 Feature Description................................................... 6
7.4 Device Functional Modes.......................................... 6
8
Application and Implementation .......................... 8
8.1 Application Information.............................................. 8
8.2 Typical Applications .................................................. 8
9 Power Supply Recommendations...................... 10
10 Layout................................................................... 10
10.1 Layout Guidelines ................................................. 10
10.2 Layout Example .................................................... 10
11 Device and Documentation Support ................. 11
11.1
11.2
11.3
11.4
11.5
11.6
Documentation Support ........................................
Receiving Notification of Documentation Updates
Community Resources..........................................
Trademarks ...........................................................
Electrostatic Discharge Caution ............................
Glossary ................................................................
11
11
11
11
11
11
12 Mechanical, Packaging, and Orderable
Information ........................................................... 11
4 Revision History
NOTE: Page numbers for previous revisions may differ from page numbers in the current version.
Changes from Revision D (May 2013) to Revision E
Page
•
Added Applications section, Device Information table, Pin Configuration and Functions section, ESD Ratings table,
Recommended Operating Conditions table, Typical Characteristics section, Detailed Description section, Application
and Implementation section, Power Supply Recommendations section, Layout section, Device and Documentation
Support section, and Mechanical, Packaging, and Orderable Information section................................................................ 1
•
Deleted DSBGA Package references throughout the data sheet .......................................................................................... 1
•
Deleted soldering information rows from Absolute Maximum Ratings table .......................................................................... 3
•
Added Thermal Information table ........................................................................................................................................... 4
•
Changed RθJA values for D (SOIC) package From: 180 To: 111.3 and for LP (TO-92) package From: 160 To: 156.9 ........ 4
Changes from Revision C (May 2013) to Revision D
•
2
Page
Changed layout of National Semiconductor Data Sheet to TI format .................................................................................... 1
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SNVS780E – MAY 1998 – REVISED DECEMBER 2016
5 Pin Configuration and Functions
D Package
8-Pin SOIC
Top View
LP Package
3-Pin TO-92
Bottom View
Pin Functions
PIN
NAME
I/O
TO-92
SOIC
ADJ
1
4
NC
—
VIN
3
VOUT
2
1
Output
DESCRIPTION
—
Adjust pin
5, 8
—
No connection
2, 3, 6, 7
Input
Input voltage pin for the regulator
Output voltage pin for the regulator
6 Specifications
6.1 Absolute Maximum Ratings
See
(1) (2)
MIN
Input-output voltage differential
Power dissipation
(2)
UNIT
40
V
Internally Limited
Storage temperature, Tstg
(1)
MAX
–55
150
°C
Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings
only, which do not imply functional operation of the device at these or any other conditions beyond those indicated under Recommended
Operating Conditions. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.
If Military/Aerospace specified devices are required, please contact the Texas Instruments Sales Office/Distributors for availability and
specifications.
6.2 ESD Ratings
V(ESD)
(1)
(2)
Electrostatic discharge
Human-body model (HBM), per ANSI/ESDA/JEDEC JS-001 (1) (2)
VALUE
UNIT
±1500
V
JEDEC document JEP155 states that 500-V HBM allows safe manufacturing with a standard ESD control process. Pins listed as ±1500
V may actually have higher performance.
Human-body model, 1.5k Ω in series with 100 pF.
6.3 Recommended Operating Conditions
over operating free-air temperature range (unless otherwise noted)
Operating junction temperature
MIN
MAX
UNIT
–25
125
°C
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SNVS780E – MAY 1998 – REVISED DECEMBER 2016
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6.4 Thermal Information
LM337L
THERMAL METRIC (1)
D (SOIC)
LP (TO-92)
8 PINS
3 PINS
UNIT
RθJA
Junction-to-ambient thermal resistance
111.3
156.9
°C/W
RθJC(top)
Junction-to-case (top) thermal resistance
56.1
80.2
°C/W
RθJB
Junction-to-board thermal resistance
51.9
—
°C/W
ψJT
Junction-to-top characterization parameter
10.6
24.7
°C/W
ψJB
Junction-to-board characterization parameter
51.3
136.2
°C/W
(1)
For more information about traditional and new thermal metrics, see the Semiconductor and IC Package Thermal Metrics application
report.
6.5 Electrical Characteristics (1)
PARAMETER
TEST CONDITIONS
Line regulation (2)
TA = 25°C, 3 V ≤ |VIN – VOUT| ≤ 40 V
Load regulation (2)
TA = 25°C, 5 mA ≤ IOUT ≤ IMAX
Thermal regulation
TA = 25°C, 10-ms Pulse
MIN
Adjustment pin current
Adjustment pin current change
5 mA ≤ IL ≤ 100 mA, 3 V ≤ |VIN – VOUT| ≤ 40 V
Reference voltage
3 V ≤ |VIN – VOUT| ≤ 40 V, 10 mA ≤ IOUT ≤ 100 mA, P ≤
625 mW
Line regulation
(2)
3 V ≤ |VIN – VOUT| ≤ 40 V
Load regulation (2)
5 mA ≤ IOUT ≤ 100 mA
Temperature stability
TMIN ≤ Tj ≤ TMAX
Minimum load current
Current limit
RMS output noise, % of VOUT
Ripple rejection ratio
Long-term stability
(1)
(2)
4
1.2
TYP
MAX
UNIT
0.01
0.04
%/V
0.1%
0.5%
0.04
0.2
%/W
50
100
μA
0.2
5
μA
1.25
1.3
V
0.02
0.07
%/V
0.3%
1.5%
0.65%
|VIN – VOUT| ≤ 40 V
3.5
5
mA
3 V ≤ |VIN – VOUT| ≤ 15 V
2.2
3.5
mA
100
200
320
mA
25
50
120
mA
3 V ≤ |VIN – VOUT| ≤ 13 V
|VIN – VOUT| = 40 V
TA = 25°C, 10 Hz ≤ f ≤ 10 kHz
0.003%
VOUT = –10 V, F = 120 Hz, CADJ = 0
CADJ = 10 μF
65
66
TA = 125°C
dB
80
0.3%
dB
1%
Unless otherwise specified, these specifications apply –25°C ≤ TJ ≤ 125°C for the LM337L; |VIN – VOUT| = 5 V and IOUT = 40 mA.
Although power dissipation is internally limited, these specifications are applicable for power dissipations up to 625 mW. IMAX is 100 mA.
Regulation is measured at constant junction temperature, using pulse testing with a low duty cycle. Changes in output voltage due to
heating effects are covered under the specification for thermal regulation.
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SNVS780E – MAY 1998 – REVISED DECEMBER 2016
140
5.37
120
5.36
100
5.35
80
5.34
IQ (mA)
Input-Output Voltage Differential (V)
6.6 Typical Characteristics
60
5.33
40
5.32
20
5.31
5.3
0
0
5
10
15
Current (mA)
20
25
0
D001
5
10
15
20
25
30
Input-Output Voltage Differential (V)
35
Figure 1. Current Limit
Figure 2. Minimum Operating Current
Figure 3. Line Transient Response
Figure 4. Load Transient Response
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D001
5
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SNVS780E – MAY 1998 – REVISED DECEMBER 2016
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7 Detailed Description
7.1 Overview
The LM337L devices are adjustable 3-terminal negative-voltage regulators capable of supplying 100 mA over an
output voltage range of –1.2 V to –37 V. They are exceptionally easy to use, requiring only two external resistors
to set the output voltage and one output capacitor for frequency compensation. In addition, LM337L offers full
overload protection. Included on the chip are current limit, thermal overload protection and safe area protection.
All overload protection circuitry remains fully functional even if the adjustment terminal is disconnected. The
LMx37 devices serve a wide variety of applications, including local on-card regulation, programmable outputvoltage regulation, and precision current regulation.
7.2 Functional Block Diagram
OUTPUT
IADJ
+
ADJUST
+ 1.25 V
Over temp
& over
current
protection
INPUT
Copyright © 2016, Texas Instruments Incorporated
7.3 Feature Description
7.3.1 Output Voltage Adjustment
The Adjustment (ADJ) pin serves as a voltage adjustment reference for the output. The ADJ pin can be attached
to a resistor divider circuit to adjust the output voltage level. The reference voltage VADJ will typically be 1.25 V
higher than VO.
7.4 Device Functional Modes
7.4.1 Protection Diodes
When external capacitors are used with any IC regulator, it is sometimes necessary to add protection diodes to
prevent the capacitors from discharging through low current points into the regulator. Most 10-μF capacitors have
low enough internal series resistance to deliver 20-A spikes when shorted. Although the surge is short, there is
enough energy to damage parts of the IC. When an output capacitor is connected to a negative output regulator
and the input is shorted, the output capacitor pulls current out of the output of the regulator. The current depends
on the value of the capacitor, the output voltage of the regulator, and the rate at which VIN is shorted to ground.
The bypass capacitor on the adjustment terminal can discharge through a low current junction. Discharge occurs
when either the input, or the output, is shorted. Figure 15 shows the placement of the protection diodes.
6
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Device Functional Modes (continued)
When CL is larger than 20 μF, D1 protects the LM337L in case the input supply is shorted.
When C2 is larger than 10 μF and −VOUT is larger than −25V, D2 protects the LM337L in case the output is shorted.
Figure 5. Regulator With Protection Diodes
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LM337L
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8 Application and Implementation
NOTE
Information in the following applications sections is not part of the TI component
specification, and TI does not warrant its accuracy or completeness. TI’s customers are
responsible for determining suitability of components for their purposes. Customers should
validate and test their design implementation to confirm system functionality.
8.1 Application Information
The LM337L is a negative output linear regulator with high accuracy and a wide temperature range. An output
capacitor can be added to further improve transient response, and the ADJ pin can be bypassed to achieve very
high ripple-rejection ratios. The device's functionality can be utilized in many different applications that require
negative voltage supplies, such as bipolar amplifiers, operational amplifiers, and constant current regulators.
8.2 Typical Applications
8.2.1 1.2-V to 25-V Adjustable Regulator
R2
+
C2
ADJ
-VIN
VIN
LM337L
VOUT
R1
240 Ÿ
+
C1
1 µF
Copyright © 2016, Texas Instruments Incorporated
Full output current not available at high input-output voltages
†C1 = 1-μF solid tantalum or 10-μF aluminum electrolytic required for stability
*C2 = 1-μF solid tantalum is required only if regulator is more than 4″ from power supply filter capacitor
Figure 6. 1.2-V to 25-V Adjustable Regulator Diagram
8.2.1.1 Design Requirements
The device component count is very minimal, employing two resistors as part of a voltage divider circuit and an
output capacitor for load regulation. An input capacitor is needed if the device is more than 4 in. from the filter
capacitors.
8.2.1.2 Detailed Design Procedure
The output voltage is set based on the selection of the two resistors (R1 and R2) as shown in Equation 1.
VOUT
8
§
R2 ·
1.25 V ¨ 1
¸
240 : ¹
©
(1)
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Typical Applications (continued)
8.2.1.3 Application Curve
Figure 7. Dropout Voltage across Load Current at 25°C (∆Vout < 100 mV
8.2.2 Regulator With Trimmable Output Voltage
R2
3.92 Ÿ
± 1%
R1
249 Ÿ
1%
ADJ
LM337L
R3
3.9 Ÿ
5%
R4
8.2 Ÿ
5%
R5
16 Ÿ
5%
VOUT
+ 1 µf
SOLID
TANTALUM
-22 V
-VIN (-25 V TO -40 V)
Copyright © 2016, Texas Instruments Incorporated
Figure 8. Regulator with Trimmable Output Voltage Diagram
8.2.2.1 Design Requirements
This design uses five resistors with two being used for a voltage divider circuit and the other three used for
trimming the output voltage. The benefit is lower cost as compared to using a trim pot. An output capacitor is
needed to improve load regulation.
8.2.2.2 Detailed Design Procedure
This design will trim the output voltage to within 1% of –22 V. The parallel combination of R1, R3, R4 and R5
serve as the bottom resistance and R2 as the top resistance in the voltage divider that sets the output voltage.
Trim Procedure:
• If VOUT is –23.08 V or larger, do not use R3, otherwise leave it in.
• Then if VOUT is –22.47 V or bigger, do not use R4, otherwise leave it in.
• Then if VOUT is –22.16 V or bigger, do not use R5, otherwise leave it in.
This will trim the output to well within 1% of –22 VDC, without any of the expense or trouble of a trim pot (see LB46). This technique can be used at any output voltage level.
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9 Power Supply Recommendations
The input supply to the LM337L must be kept at a voltage level such that its maximum input to output differential
voltage rating is not exceeded. The minimum dropout voltage must also be met with extra headroom when
possible to keep the LM337L in regulation. TI recommends an input capacitor, especially when the input pin is
placed more than 4 in. away from the power-supply filter capacitor.
10 Layout
10.1 Layout Guidelines
Some layout guidelines must be followed to ensure proper regulation of the output voltage with minimum noise.
Traces carrying the load current must be wide to reduce the amount of parasitic trace inductance and the
feedback loop from VOUT to ADJ must be kept as short as possible. To improve PSRR, a bypass capacitor can
be placed at the ADJ pin and must be placed as close as possible to the IC. In cases when VIN shorts to ground,
an external diode must be placed from VIN to VOUT to divert the surge current into the output capacitor and
protect the IC. Similarly, in cases when a large bypass capacitor is placed at the ADJ pin and VOUT shorts to
ground, an external diode must be placed from VOUT to ADJ to provide a path for the bypass capacitor to
discharge. These diodes must be placed close to the corresponding IC pins to increase their effectiveness.
10.2 Layout Example
Figure 9. LM337L Layout Example
10
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11 Device and Documentation Support
11.1 Documentation Support
11.1.1 Related Documentation
For related documentation see the following:
• LM317L-N 3-Terminal Adjustable Regulator (SNOSBW2)
• LM117, LM317-N Wide Temperature Three-Pin Adjustable Regulator (SNVS774)
• LM317L-N 3-Terminal Adjustable Regulator (SNVS775)
11.2 Receiving Notification of Documentation Updates
To receive notification of documentation updates, navigate to the device product folder on ti.com. In the upper
right corner, click on Alert me to register and receive a weekly digest of any product information that has
changed. For change details, review the revision history included in any revised document.
11.3 Community Resources
The following links connect to TI community resources. Linked contents are provided "AS IS" by the respective
contributors. They do not constitute TI specifications and do not necessarily reflect TI's views; see TI's Terms of
Use.
TI E2E™ Online Community TI's Engineer-to-Engineer (E2E) Community. Created to foster collaboration
among engineers. At e2e.ti.com, you can ask questions, share knowledge, explore ideas and help
solve problems with fellow engineers.
Design Support TI's Design Support Quickly find helpful E2E forums along with design support tools and
contact information for technical support.
11.4 Trademarks
E2E is a trademark of Texas Instruments.
All other trademarks are the property of their respective owners.
11.5 Electrostatic Discharge Caution
This integrated circuit can be damaged by ESD. Texas Instruments recommends that all integrated circuits be handled with
appropriate precautions. Failure to observe proper handling and installation procedures can cause damage.
ESD damage can range from subtle performance degradation to complete device failure. Precision integrated circuits may be more
susceptible to damage because very small parametric changes could cause the device not to meet its published specifications.
11.6 Glossary
SLYZ022 — TI Glossary.
This glossary lists and explains terms, acronyms, and definitions.
12 Mechanical, Packaging, and Orderable Information
The following pages include mechanical, packaging, and orderable information. This information is the most
current data available for the designated devices. This data is subject to change without notice and revision of
this document. For browser-based versions of this data sheet, refer to the left-hand navigation.
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PACKAGE OPTION ADDENDUM
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11-Dec-2021
PACKAGING INFORMATION
Orderable Device
Status
(1)
Package Type Package Pins Package
Drawing
Qty
Eco Plan
(2)
Lead finish/
Ball material
MSL Peak Temp
Op Temp (°C)
Device Marking
(3)
(4/5)
(6)
LM337LM
NRND
SOIC
D
8
95
Non-RoHS
& Green
Call TI
Level-1-235C-UNLIM
-25 to 100
LM337
LM
LM337LM/NOPB
ACTIVE
SOIC
D
8
95
RoHS & Green
SN
Level-1-260C-UNLIM
-25 to 100
LM337
LM
LM337LMX
NRND
SOIC
D
8
2500
Non-RoHS
& Green
Call TI
Level-1-235C-UNLIM
-25 to 100
LM337
LM
LM337LMX/NOPB
ACTIVE
SOIC
D
8
2500
RoHS & Green
SN
Level-1-260C-UNLIM
-25 to 100
LM337
LM
LM337LZ/LFT3
ACTIVE
TO-92
LP
3
2000
RoHS & Green
SN
N / A for Pkg Type
LM337LZ/NOPB
ACTIVE
TO-92
LP
3
1800
RoHS & Green
SN
N / A for Pkg Type
LM337
LZ
-25 to 100
LM337
LZ
(1)
The marketing status values are defined as follows:
ACTIVE: Product device recommended for new designs.
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design.
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.
OBSOLETE: TI has discontinued the production of the device.
(2)
RoHS: TI defines "RoHS" to mean semiconductor products that are compliant with the current EU RoHS requirements for all 10 RoHS substances, including the requirement that RoHS substance
do not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, "RoHS" products are suitable for use in specified lead-free processes. TI may
reference these types of products as "Pb-Free".
RoHS Exempt: TI defines "RoHS Exempt" to mean products that contain lead but are compliant with EU RoHS pursuant to a specific EU RoHS exemption.
Green: TI defines "Green" to mean the content of Chlorine (Cl) and Bromine (Br) based flame retardants meet JS709B low halogen requirements of