TI LM2675M-ADJ

LM2675
www.ti.com
SNVS129E – MAY 2004 – REVISED JUNE 2005
LM2675 SIMPLE SWITCHER® Power Converter High Efficiency 1A Step-Down Voltage
Regulator
Check for Samples: LM2675
FEATURES
DESCRIPTION
• Efficiency up to 96%
• Available in 8-pin SOIC and PDIP Packages
and a 16-pin WSON Package
• Computer Design Software LM267X Made
Simple (version 6.0)
• Simple and Easy to Design with
• Requires Only 5 External Components
• Uses Readily Available Standard Inductors
• 3.3V, 5.0V, 12V, and Adjustable Output
Versions
• Adjustable Version Output Voltage Range:
1.21V to 37V
• ±1.5% Max Output Voltage Tolerance Over
Line and Load Conditions
• Ensured 1A Output Load Current
• 0.25Ω DMOS Output Switch
• Wide Input Voltage Range: 8V to 40V
• 260 kHz Fixed Frequency Internal Oscillator
• TTL Shutdown Capability, Low Power Standby
Mode
• Thermal Shutdown and Current Limit
Protection
The LM2675 series of regulators are monolithic
integrated circuits built with a LMDMOS process.
These regulators provide all the active functions for a
step-down (buck) switching regulator, capable of
driving a 1A load current with excellent line and load
regulation. These devices are available in fixed output
voltages of 3.3V, 5.0V, 12V, and an adjustable output
version.
TYPICAL APPLICATIONS
Other features include a ensured ±1.5% tolerance on
output voltage within specified input voltages and
output load conditions, and ±10% on the oscillator
frequency. External shutdown is included, featuring
typically 50 μA stand-by current. The output switch
includes current limiting, as well as thermal shutdown
for full protection under fault conditions.
1
234
•
•
•
Simple High Efficiency (>90%) Step-Down
(Buck) Regulator
Efficient Pre-Regulator for Linear Regulators
Positive-to-Negative Converter
Requiring a minimum number of external
components, these regulators are simple to use and
include patented internal frequency compensation
(Patent Nos. 5,382,918 and 5,514,947) and a fixed
frequency oscillator.
The LM2675 series operates at a switching frequency
of 260 kHz, thus allowing smaller sized filter
components than what would be needed with lower
frequency switching regulators. Because of its very
high efficiency (>90%), the copper traces on the
printed circuit board are the only heat sinking needed.
A family of standard inductors for use with the
LM2675 are available from several different
manufacturers. This feature greatly simplifies the
design of switch-mode power supplies using these
advanced ICs. Also included in the datasheet are
selector guides for diodes and capacitors designed to
work in switch-mode power supplies.
To simplify the LM2675 buck regulator design
procedure, there exists computer design software,
LM267X Made Simple version 6.0.
1
2
3
4
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
SIMPLE SWITCHER is a registered trademark of Texas Instruments.
Windows is a registered trademark of Microsoft Corporation.
All other trademarks are the property of their respective owners.
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
Copyright © 2004–2005, Texas Instruments Incorporated
LM2675
SNVS129E – MAY 2004 – REVISED JUNE 2005
www.ti.com
Typical Application
Connection Diagram
CB
1
16
VSW
*
2
15
VSW
*
3
14
VIN
DAP**
13
*
*
5
12
GND
*
6
11
GND
*
7
10
*
FB
8
9
ON/OFF
*
4
* No Connections
**Connect to Pins 11, 12 on PCB
Figure 1. 16-Lead WSON Surface Mount Package
Top View
Package Drawing Number NHN0016A
Figure 2. 8-Lead SOIC/PDIP Package
Top View
Package Drawing Number D0008A/P0008E
These devices have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam
during storage or handling to prevent electrostatic damage to the MOS gates.
2
Submit Documentation Feedback
Copyright © 2004–2005, Texas Instruments Incorporated
Product Folder Links: LM2675
LM2675
www.ti.com
SNVS129E – MAY 2004 – REVISED JUNE 2005
Absolute Maximum Ratings (1) (2)
Supply Voltage
45V
−0.1V ≤ VSH ≤ 6V
ON/OFF Pin Voltage
−1V
Switch Voltage to Ground
Boost Pin Voltage
VSW + 8V
−0.3V ≤ VFB ≤ 14V
Feedback Pin Voltage
ESD Susceptibility
Human Body Model (3)
2 kV
Power Dissipation
Internally Limited
Storage Temperature Range
−65°C to +150°C
Lead Temperature
D Package
Vapor Phase (60s)
+215°C
Infrared (15s)
+220°C
P Package (Soldering, 10s)
+260°C
WSON Package (See AN-1187 - SNOA401)
Maximum Junction Temperature
(1)
(2)
(3)
+150°C
Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for
which the device is intended to be functional, but device parameter specifications may not be ensured under these conditions. For
ensured specifications and test conditions, see the Electrical Characteristics.
If Military/Aerospace specified devices are required, please contact the Texas Instruments Sales Office/ Distributors for availability and
specifications.
The human body model is a 100 pF capacitor discharged through a 1.5 kΩ resistor into each pin.
Operating Ratings
Supply Voltage
6.5V to 40V
−40°C ≤ TJ ≤ +125°C
Junction Temperature Range
LM2675-3.3 Electrical Characteristics
Specifications with standard type face are for TJ = 25°C, and those with bold type face apply over full Operating
Temperature Range.
Symbol
Parameter
Conditions
SYSTEM PARAMETERS Test Circuit Figure 22
Typ (1)
Min (2)
Max (2)
Units
V
(3)
VOUT
Output Voltage
VIN = 8V to 40V, ILOAD = 20 mA to 1A
3.3
3.251/3.201
3.350/3.399
VOUT
Output Voltage
VIN = 6.5V to 40V, ILOAD = 20 mA to 500 mA
3.3
3.251/3.201
3.350/3.399
η
Efficiency
VIN = 12V, ILOAD = 1A
86
(1)
(2)
(3)
V
%
Typical numbers are at 25°C and represent the most likely norm.
All limits specified at room temperature (standard type face) and at temperature extremes (bold type face). All room temperature limits
are 100% production tested. All limits at temperature extremes are specified via correlation using standard Statistical Quality Control
(SQC) methods. All limits are used to calculate Average Outgoing Quality Level (AOQL).
External components such as the catch diode, inductor, input and output capacitors, and voltage programming resistors can affect
switching regulator performance. When the LM2675 is used as shown in Figure 22 and Figure 23 test circuits, system performance will
be as specified by the system parameters section of the Electrical Characteristics.
Submit Documentation Feedback
Copyright © 2004–2005, Texas Instruments Incorporated
Product Folder Links: LM2675
3
LM2675
SNVS129E – MAY 2004 – REVISED JUNE 2005
www.ti.com
LM2675-5.0 Electrical Characteristics
Symbol
Parameter
Conditions
SYSTEM PARAMETERS Test Circuit Figure 22
Typ (1)
Min (2)
Max (2)
Units
(3)
VOUT
Output Voltage
VIN = 8V to 40V, ILOAD = 20 mA to 1A
5.0
4.925/4.850
5.075/5.150
V
VOUT
Output Voltage
VIN = 6.5V to 40V, ILOAD = 20 mA to 500 mA
5.0
4.925/4.850
5.075/5.150
V
η
Efficiency
VIN = 12V, ILOAD = 1A
90
(1)
(2)
(3)
%
Typical numbers are at 25°C and represent the most likely norm.
All limits specified at room temperature (standard type face) and at temperature extremes (bold type face). All room temperature limits
are 100% production tested. All limits at temperature extremes are specified via correlation using standard Statistical Quality Control
(SQC) methods. All limits are used to calculate Average Outgoing Quality Level (AOQL).
External components such as the catch diode, inductor, input and output capacitors, and voltage programming resistors can affect
switching regulator performance. When the LM2675 is used as shown in Figure 22 and Figure 23 test circuits, system performance will
be as specified by the system parameters section of the Electrical Characteristics.
LM2675-12 Electrical Characteristics
Symbol
Parameter
Conditions
SYSTEM PARAMETERS Test Circuit Figure 22
Typ (1)
Min (2)
Max (2)
11.82/11.64
12.18/12.36
VOUT
Output Voltage
VIN = 15V to 40V, ILOAD = 20 mA to 1A
12
η
Efficiency
VIN = 24V, ILOAD = 1A
94
(1)
(2)
(3)
Units
(3)
V
%
Typical numbers are at 25°C and represent the most likely norm.
All limits specified at room temperature (standard type face) and at temperature extremes (bold type face). All room temperature limits
are 100% production tested. All limits at temperature extremes are specified via correlation using standard Statistical Quality Control
(SQC) methods. All limits are used to calculate Average Outgoing Quality Level (AOQL).
External components such as the catch diode, inductor, input and output capacitors, and voltage programming resistors can affect
switching regulator performance. When the LM2675 is used as shown in Figure 22 and Figure 23 test circuits, system performance will
be as specified by the system parameters section of the Electrical Characteristics.
LM2675-ADJ Electrical Characteristics
Symbol
Typ (1)
Min (2)
Max (2)
Units
VIN = 8V to 40V, ILOAD = 20 mA to 1A
VOUT Programmed for 5V
(see Circuit of Figure 23)
1.210
1.192/1.174
1.228/1.246
V
VIN = 6.5V to 40V, ILOAD = 20 mA to 500 mA
VOUT Programmed for 5V
(see Circuit of Figure 23)
1.210
1.192/1.174
1.228/1.246
V
Parameter
Conditions
SYSTEM PARAMETERS Test Circuit Figure 23 (3)
VFB
Feedback Voltage
VFB
Feedback Voltage
η
Efficiency
(1)
(2)
(3)
VIN = 12V, ILOAD = 1A
90
%
Typical numbers are at 25°C and represent the most likely norm.
All limits specified at room temperature (standard type face) and at temperature extremes (bold type face). All room temperature limits
are 100% production tested. All limits at temperature extremes are specified via correlation using standard Statistical Quality Control
(SQC) methods. All limits are used to calculate Average Outgoing Quality Level (AOQL).
External components such as the catch diode, inductor, input and output capacitors, and voltage programming resistors can affect
switching regulator performance. When the LM2675 is used as shown in Figure 22 and Figure 23 test circuits, system performance will
be as specified by the system parameters section of the Electrical Characteristics.
All Output Voltage Versions Electrical Characteristics
Specifications with standard type face are for TJ = 25°C, and those with bold type face apply over full Operating
Temperature Range. Unless otherwise specified, VIN = 12V for the 3.3V, 5V, and Adjustable versions and VIN = 24V for the
12V version, and ILOAD = 100 mA.
Symbol
Parameters
Conditions
Typ
Min
Max
Units
3.6
mA
DEVICE PARAMETERS
IQ
Quiescent Current
ISTBY
Standby Quiescent Current
ICL
Current Limit
4
VFEEDBACK = 8V
For 3.3V, 5.0V, and ADJ Versions
2.5
VFEEDBACK = 15V
For 12V Versions
2.5
ON/OFF Pin = 0V
50
1.55
Submit Documentation Feedback
mA
1.25/1.2
100/150
μA
2.1/2.2
A
Copyright © 2004–2005, Texas Instruments Incorporated
Product Folder Links: LM2675
LM2675
www.ti.com
SNVS129E – MAY 2004 – REVISED JUNE 2005
All Output Voltage Versions Electrical Characteristics (continued)
Specifications with standard type face are for TJ = 25°C, and those with bold type face apply over full Operating
Temperature Range. Unless otherwise specified, VIN = 12V for the 3.3V, 5V, and Adjustable versions and VIN = 24V for the
12V version, and ILOAD = 100 mA.
Symbol
Parameters
Conditions
VIN = 40V, ON/OFF Pin = 0V
VSWITCH = 0V
Typ
Max
Units
25
μA
6
15
mA
0.25
0.30/0.50
Ω
275
kHz
IL
Output Leakage Current
RDS(ON)
Switch On-Resistance
ISWITCH = 1A
fO
Oscillator Frequency
Measured at Switch Pin
260
D
Maximum Duty Cycle
VSWITCH = −1V, ON/OFF Pin = 0V
Minimum Duty Cycle
IBIAS
Feedback Bias
Current
VS/D
ON/OFF Pin
Voltage Thesholds
IS/D
ON/OFF Pin Current
θJA
Thermal Resistance
(1)
VFEEDBACK = 1.3V
ADJ Version Only
Min
1
225
95
%
0
%
85
nA
1.4
0.8
2.0
ON/OFF Pin = 0V
20
7
37
P Package, Junction to Ambient (1)
D Package, Junction to Ambient (1)
95
V
μA
°C/W
105
Junction to ambient thermal resistance with approximately 1 square inch of printed circuit board copper surrounding the leads. Additional
copper area will lower thermal resistance further. See Application Information section in the application note accompanying this
datasheet and the thermal model in LM267X Made Simple software (version 6.0). The value θJ−A for the WSON (NHN) package is
specifically dependent on PCB trace area, trace material, and the number of layers and thermal vias. For improved thermal resistance
and power dissipation for the WSON package, refer to Application Note AN-1187 (SNOA401).
Submit Documentation Feedback
Copyright © 2004–2005, Texas Instruments Incorporated
Product Folder Links: LM2675
5
LM2675
SNVS129E – MAY 2004 – REVISED JUNE 2005
www.ti.com
Typical Performance Characteristics
6
Normalized
Output Voltage
Line Regulation
Figure 3.
Figure 4.
Efficiency
Drain-to-Source
Resistance
Figure 5.
Figure 6.
Switch Current Limit
Operating
Quiescent Current
Figure 7.
Figure 8.
Submit Documentation Feedback
Copyright © 2004–2005, Texas Instruments Incorporated
Product Folder Links: LM2675
LM2675
www.ti.com
SNVS129E – MAY 2004 – REVISED JUNE 2005
Typical Performance Characteristics (continued)
Standby
Quiescent Current
ON/OFF Threshold
Voltage
Figure 9.
Figure 10.
ON/OFF Pin
Current (Sourcing)
Switching Frequency
Figure 11.
Figure 12.
Feedback Pin
Bias Current
Peak Switch Current
Figure 13.
Figure 14.
Submit Documentation Feedback
Copyright © 2004–2005, Texas Instruments Incorporated
Product Folder Links: LM2675
7
LM2675
SNVS129E – MAY 2004 – REVISED JUNE 2005
www.ti.com
Typical Performance Characteristics (continued)
Dropout Voltage—3.3V Option
Dropout Voltage—5.0V Option
Figure 15. m
Figure 16.
Block Diagram
* Active Inductor Patent Number 5,514,947
† Active Capacitor Patent Number 5,382,918
Figure 17.
8
Submit Documentation Feedback
Copyright © 2004–2005, Texas Instruments Incorporated
Product Folder Links: LM2675
LM2675
www.ti.com
SNVS129E – MAY 2004 – REVISED JUNE 2005
Typical Performance Characteristics
(Circuit of Figure 22)
Continuous Mode Switching Waveforms
VIN = 20V, VOUT = 5V, ILOAD = 1A
L = 47 μH, COUT = 68 μF, COUTESR = 50 mΩ
A: VSW Pin Voltage, 10 V/div.
B: Inductor Current, 0.5 A/div
C: Output Ripple Voltage, 20 mV/div AC-Coupled
Figure 18. Horizontal Time Base: 1 μs/div
Load Transient Response for Continuous Mode
VIN = 20V, VOUT = 5V, ILOAD = 1A
L = 47 μH, COUT = 68 μF, COUTESR = 50 mΩ
A: Output Voltage, 100 mV/div, AC-Coupled.
B: Load Current: 200 mA to 1A Load Pulse
Figure 20. Horizontal Time Base: 50 μs/div
Discontinuous Mode Switching Waveforms
VIN = 20V, VOUT = 5V, ILOAD = 300 mA
L = 15 μH, COUT = 68 μF (2×), COUTESR = 25 mΩ
A: VSW Pin Voltage, 10 V/div.
B: Inductor Current, 0.5 A/div
C: Output Ripple Voltage, 20 mV/div AC-Coupled
Figure 19. Horizontal Time Base: 1 μs/div
Load Transient Response for Discontinuous Mode
VIN = 20V, VOUT = 5V,
L = 47 μH, COUT = 68 μF, COUTESR = 50 mΩ
A: Output Voltage, 100 mV/div, AC-Coupled.
B: Load Current: 100 mA to 400 mA Load Pulse
Figure 21. Horizontal Time Base: 200 μs/div
Submit Documentation Feedback
Copyright © 2004–2005, Texas Instruments Incorporated
Product Folder Links: LM2675
9
LM2675
SNVS129E – MAY 2004 – REVISED JUNE 2005
www.ti.com
Test Circuit and Layout Guidelines
CIN - 22 μF, 50V Tantalum, Sprague “199D Series”
COUT - 47 μF, 25V Tantalum, Sprague “595D Series”
D1 - 3.3A, 50V Schottky Rectifier, IR 30WQ05F
L1 - 68 μH Sumida #RCR110D-680L
CB - 0.01 μF, 50V Ceramic
Figure 22. Standard Test Circuits and Layout Guides
Fixed Output Voltage Versions
CIN - 22 μF, 50V Tantalum, Sprague “199D Series”
COUT - 47 μF, 25V Tantalum, Sprague “595D Series”
D1 - 3.3A, 50V Schottky Rectifier, IR 30WQ05F
L1 - 68 μH Sumida #RCR110D-680L
R1 - 1.5 kΩ, 1%
CB - 0.01 μF, 50V Ceramic
For a 5V output, select R2 to be 4.75 kΩ, 1%
where VREF = 1.21V
Use a 1% resistor for best stability.
Figure 23. Standard Test Circuits and Layout Guides
Adjustable Output Voltage Version
10
Submit Documentation Feedback
Copyright © 2004–2005, Texas Instruments Incorporated
Product Folder Links: LM2675
LM2675
www.ti.com
SNVS129E – MAY 2004 – REVISED JUNE 2005
LM2675 Series Buck Regulator Design Procedure (Fixed Output)
PROCEDURE (Fixed Output Voltage Version)
EXAMPLE (Fixed Output Voltage Version)
To simplify the buck regulator design procedure, Texas Instruments
is making available computer design software to be used with the
SIMPLE SWITCHERline of switching regulators.LM267X Made
Simpleversion 6.0 is available on Windows® 3.1, NT, or 95 operating
systems.
Given:
Given:
VOUT = Regulated Output Voltage (3.3V, 5V, or 12V)
VOUT = 5V
VIN(max) = Maximum DC Input Voltage
VIN(max) = 12V
ILOAD(max) = Maximum Load Current
ILOAD(max) = 1A
1. Inductor Selection (L1)
1. Inductor Selection (L1)
A. Select the correct inductor value selection guide from Figure 24,
A. Use the inductor selection guide for the 5V version shown in
Figure 25 or Figure 26 (output voltages of 3.3V, 5V, or 12V
Figure 25.
respectively). For all other voltages, see the design procedure for the
adjustable version.
B. From the inductor value selection guide, identify the inductance
region intersected by the Maximum Input Voltage line and the
Maximum Load Current line. Each region is identified by an
inductance value and an inductor code (LXX).
B. From the inductor value selection guide shown in Figure 25, the
inductance region intersected by the 12V horizontal line and the 1A
vertical line is 33 μH, and the inductor code is L23.
C. Select an appropriate inductor from the four manufacturer's part
numbers listed in Inductor Value Selection Guides. Each
manufacturer makes a different style of inductor to allow flexibility in
meeting various design requirements. Listed below are some of the
differentiating characteristics of each manufacturer's inductors:
C. The inductance value required is 33 μH. From the table in
Table 1, go to the L23 line and choose an inductor part number from
any of the four manufacturers shown. (In most instances, both
through hole and surface mount inductors are available.)
Schott: ferrite EP core inductors; these have very low leakage
magnetic fields to reduce electro-magnetic interference (EMI) and
are the lowest power loss inductors
Renco: ferrite stick core inductors; benefits are typically lowest cost
inductors and can withstand E•T and transient peak currents above
rated value. Be aware that these inductors have an external
magnetic field which may generate more EMI than other types of
inductors.
Pulse: powered iron toroid core inductors; these can also be low cost
and can withstand larger than normal E•T and transient peak
currents. Toroid inductors have low EMI.
Coilcraft: ferrite drum core inductors; these are the smallest physical
size inductors, available only as SMT components. Be aware that
these inductors also generate EMI—but less than stick inductors.
Complete specifications for these inductors are available from the
respective manufacturers. A table listing the manufacturers' phone
numbers is located in Table 2.
2. Output Capacitor Selection (COUT)
2. Output Capacitor Selection (COUT)
A. Select an output capacitor from the output capacitor table in
Table 3. Using the output voltage and the inductance value found in
the inductor selection guide, step 1, locate the appropriate capacitor
value and voltage rating.
A. Use the 5.0V section in the output capacitor table in Table 3.
Choose a capacitor value and voltage rating from the line that
contains the inductance value of 33 μH. The capacitance and
voltage rating values corresponding to the 33 μH inductor are the:
The capacitor list contains through-hole electrolytic capacitors from
four different capacitor manufacturers and surface mount tantalum
capacitors from two different capacitor manufacturers. It is
recommended that both the manufacturers and the manufacturer's
series that are listed in the table be used. A table listing the
manufacturers' phone numbers is located in Table 2.
Surface Mount:
68 μF/10V Sprague 594D Series.
100 μF/10V AVX TPS Series.
Through Hole:
68 μF/10V Sanyo OS-CON SA Series.
220 μF/35V Sanyo MV-GX Series.
220 μF/35V Nichicon PL Series.
220 μF/35V Panasonic HFQ Series.
Submit Documentation Feedback
Copyright © 2004–2005, Texas Instruments Incorporated
Product Folder Links: LM2675
11
LM2675
SNVS129E – MAY 2004 – REVISED JUNE 2005
www.ti.com
PROCEDURE (Fixed Output Voltage Version)
3. Catch Diode Selection (D1)
A. In normal operation, the average current of the catch diode is the
load current times the catch diode duty cycle, 1-D (D is the switch
duty cycle, which is approximately the output voltage divided by the
input voltage). The largest value of the catch diode average current
occurs at the maximum load current and maximum input voltage
(minimum D). For normal operation, the catch diode current rating
must be at least 1.3 times greater than its maximum average
current. However, if the power supply design must withstand a
continuous output short, the diode should have a current rating equal
to the maximum current limit of the LM2675. The most stressful
condition for this diode is a shorted output condition.
EXAMPLE (Fixed Output Voltage Version)
3. Catch Diode Selection (D1)
A. Refer to the table shown in Table 5. In this example, a 1A, 20V
Schottky diode will provide the best performance. If the circuit must
withstand a continuous shorted output, a higher current Schottky
diode is recommended.
B. The reverse voltage rating of the diode should be at least 1.25
times the maximum input voltage.
C. Because of their fast switching speed and low forward voltage
drop, Schottky diodes provide the best performance and efficiency.
This Schottky diode must be located close to the LM2675 using
short leads and short printed circuit traces.
4. Input Capacitor (CIN)
4. Input Capacitor (CIN)
A low ESR aluminum or tantalum bypass capacitor is needed
between the input pin and ground to prevent large voltage transients
from appearing at the input. This capacitor should be located close
to the IC using short leads. In addition, the RMS current rating of the
input capacitor should be selected to be at least ½ the DC load
current. The capacitor manufacturer data sheet must be checked to
assure that this current rating is not exceeded. The curves shown in
Figure 28 show typical RMS current ratings for several different
aluminum electrolytic capacitor values. A parallel connection of two
or more capacitors may be required to increase the total minimum
RMS current rating to suit the application requirements.
For an aluminum electrolytic capacitor, the voltage rating should be
at least 1.25 times the maximum input voltage. Caution must be
exercised if solid tantalum capacitors are used. The tantalum
capacitor voltage rating should be twice the maximum input voltage.
The tables in Table 3 show the recommended application voltage for
AVX TPS and Sprague 594D tantalum capacitors. It is also
recommended that they be surge current tested by the manufacturer.
The TPS series available from AVX, and the 593D and 594D series
from Sprague are all surge current tested. Another approach to
minimize the surge current stresses on the input capacitor is to add
a small inductor in series with the input supply line.
Use caution when using ceramic capacitors for input bypassing,
because it may cause severe ringing at the VIN pin.
The important parameters for the input capacitor are the input
voltage rating and the RMS current rating. With a maximum input
voltage of 12V, an aluminum electrolytic capacitor with a voltage
rating greater than 15V (1.25 × VIN) would be needed. The next
higher capacitor voltage rating is 16V.
The RMS current rating requirement for the input capacitor in a buck
regulator is approximately ½ the DC load current. In this example,
with a 1A load, a capacitor with a RMS current rating of at least 500
mA is needed. The curves shown in Figure 28 can be used to select
an appropriate input capacitor. From the curves, locate the 16V line
and note which capacitor values have RMS current ratings greater
than 500 mA.
For a through hole design, a 330 μF/16V electrolytic capacitor
(Panasonic HFQ series, Nichicon PL, Sanyo MV-GX series or
equivalent) would be adequate. Other types or other manufacturers'
capacitors can be used provided the RMS ripple current ratings are
adequate. Additionally, for a complete surface mount design,
electrolytic capacitors such as the Sanyo CV-C or CV-BS and the
Nichicon WF or UR and the NIC Components NACZ series could be
considered.
For surface mount designs, solid tantalum capacitors can be used,
but caution must be exercised with regard to the capacitor surge
current rating and voltage rating. In this example, checking Table 8,
and the Sprague 594D series datasheet, a Sprague 594D 15 μF,
25V capacitor is adequate.
5. Boost Capacitor (CB)
5. Boost Capacitor (CB)
This capacitor develops the necessary voltage to turn the switch
gate on fully. All applications should use a 0.01 μF, 50V ceramic
capacitor.
For this application, and all applications, use a 0.01 μF, 50V ceramic
capacitor.
12
Submit Documentation Feedback
Copyright © 2004–2005, Texas Instruments Incorporated
Product Folder Links: LM2675
LM2675
www.ti.com
SNVS129E – MAY 2004 – REVISED JUNE 2005
Inductor Value Selection Guides
(For Continuous Mode Operation)
Figure 24. LM2675-3.3
Figure 25. LM2675-5.0
Figure 26. LM2675-12
Figure 27. LM2675-ADJ
Table 1. Inductor Manufacturers' Part Numbers
Ind.
Inductance
Ref.
(μH)
Desg.
Schott
Current
(A)
Through
Renco
Surface
Hole
Mount
Through
Pulse Engineering
Surface
Through
Surface
Coilcraft
Surface
Hole
Mount
Hole
Mount
L4
68
0.32
67143940
67144310
RL-1284-68-43
RL1500-68
PE-53804
PE-53804-S
DO1608-683
Mount
L5
47
0.37
67148310
67148420
RL-1284-47-43
RL1500-47
PE-53805
PE-53805-S
DO1608-473
L6
33
0.44
67148320
67148430
RL-1284-33-43
RL1500-33
PE-53806
PE-53806-S
DO1608-333
L7
22
0.52
67148330
67148440
RL-1284-22-43
RL1500-22
PE-53807
PE-53807-S
DO1608-223
L9
220
0.32
67143960
67144330
RL-5470-3
RL1500-220
PE-53809
PE-53809-S
DO3308-224
L10
150
0.39
67143970
67144340
RL-5470-4
RL1500-150
PE-53810
PE-53810-S
DO3308-154
L11
100
0.48
67143980
67144350
RL-5470-5
RL1500-100
PE-53811
PE-53811-S
DO3308-104
L12
68
0.58
67143990
67144360
RL-5470-6
RL1500-68
PE-53812
PE-53812-S
DO3308-683
L13
47
0.70
67144000
67144380
RL-5470-7
RL1500-47
PE-53813
PE-53813-S
DO3308-473
L14
33
0.83
67148340
67148450
RL-1284-33-43
RL1500-33
PE-53814
PE-53814-S
DO3308-333
L15
22
0.99
67148350
67148460
RL-1284-22-43
RL1500-22
PE-53815
PE-53815-S
DO3308-223
L18
220
0.55
67144040
67144420
RL-5471-2
RL1500-220
PE-53818
PE-53818-S
DO3316-224
L19
150
0.66
67144050
67144430
RL-5471-3
RL1500-150
PE-53819
PE-53819-S
DO3316-154
L20
100
0.82
67144060
67144440
RL-5471-4
RL1500-100
PE-53820
PE-53820-S
DO3316-104
L21
68
0.99
67144070
67144450
RL-5471-5
RL1500-68
PE-53821
PE-53821-S
DO3316-683
L22
47
1.17
67144080
67144460
RL-5471-6
—
PE-53822
PE-53822-S
DO3316-473
Submit Documentation Feedback
Copyright © 2004–2005, Texas Instruments Incorporated
Product Folder Links: LM2675
13
LM2675
SNVS129E – MAY 2004 – REVISED JUNE 2005
www.ti.com
Table 1. Inductor Manufacturers' Part Numbers (continued)
Schott
Ind.
Inductance
Ref.
(μH)
Desg.
Current
(A)
Through
Renco
Surface
Hole
Mount
Pulse Engineering
Through
Surface
Through
Surface
Coilcraft
Surface
Hole
Mount
Hole
Mount
L23
33
1.40
67144090
67144470
RL-5471-7
—
PE-53823
PE-53823-S
DO3316-333
Mount
L24
22
1.70
67148370
67148480
RL-1283-22-43
—
PE-53824
PE-53824-S
DO3316-223
L27
220
1.00
67144110
67144490
RL-5471-2
—
PE-53827
PE-53827-S
DO5022P-224
L28
150
1.20
67144120
67144500
RL-5471-3
—
PE-53828
PE-53828-S
DO5022P-154
L29
100
1.47
67144130
67144510
RL-5471-4
—
PE-53829
PE-53829-S
DO5022P-104
L30
68
1.78
67144140
67144520
RL-5471-5
—
PE-53830
PE-53830-S
DO5022P-683
Table 2. Inductor Manufacturers' Phone Numbers
Coilcraft Inc.
Coilcraft Inc., Europe
Pulse Engineering Inc.
Pulse Engineering Inc., Europe
Renco Electronics Inc.
Schott Corp.
Phone
(800) 322-2645
FAX
(708) 639-1469
Phone
+44 1236 730 595
FAX
+44 1236 730 627
Phone
(619) 674-8100
FAX
(619) 674-8262
Phone
+353 93 24 107
FAX
+353 93 24 459
Phone
(800) 645-5828
FAX
(516) 586-5562
Phone
(612) 475-1173
FAX
(612) 475-1786
Table 3. Output Capacitor Table
Output Capacitor
Output
Voltage
(V)
3.3
5.0
14
Surface Mount
Inductance
(μH)
Through Hole
Sprague
AVX TPS
Sanyo OS-CON
Sanyo MV-GX
Nichicon
Panasonic
594D Series
Series
SA Series
Series
PL Series
HFQ Series
(μF/V)
(μF/V)
(μF/V)
(μF/V)
(μF/V)
(μF/V)
22
120/6.3
100/10
100/10
330/35
330/35
330/35
33
120/6.3
100/10
68/10
220/35
220/35
220/35
47
68/10
100/10
68/10
150/35
150/35
150/35
68
120/6.3
100/10
100/10
120/35
120/35
120/35
100
120/6.3
100/10
100/10
120/35
120/35
120/35
150
120/6.3
100/10
100/10
120/35
120/35
120/35
22
100/16
100/10
100/10
330/35
330/35
330/35
33
68/10
10010
68/10
220/35
220/35
220/35
47
68/10
100/10
68/10
150/35
150/35
150/35
68
100/16
100/10
100/10
120/35
120/35
120/35
100
100/16
100/10
100/10
120/35
120/35
120/35
150
100/16
100/10
100/10
120/35
120/35
120/35
Submit Documentation Feedback
Copyright © 2004–2005, Texas Instruments Incorporated
Product Folder Links: LM2675
LM2675
www.ti.com
SNVS129E – MAY 2004 – REVISED JUNE 2005
Table 3. Output Capacitor Table (continued)
Output Capacitor
Output
Voltage
(V)
Surface Mount
Inductance
(μH)
12
Through Hole
Sprague
AVX TPS
Sanyo OS-CON
Sanyo MV-GX
Nichicon
Panasonic
594D Series
Series
SA Series
Series
PL Series
HFQ Series
(μF/V)
(μF/V)
(μF/V)
(μF/V)
(μF/V)
(μF/V)
22
120/20
(2×) 68/20
68/20
330/35
330/35
330/35
33
68/25
68/20
68/20
220/35
220/35
220/35
47
47/20
68/20
47/20
150/35
150/35
150/35
68
47/20
68/20
47/20
120/35
120/35
120/35
100
47/20
68/20
47/20
120/35
120/35
120/35
150
47/20
68/20
47/20
120/35
120/35
120/35
220
47/20
68/20
47/20
120/35
120/35
120/35
Table 4. Capacitor Manufacturers' Phone Numbers
Nichicon Corp.
Panasonic
AVX Corp.
Sprague/Vishay
Sanyo Corp.
Phone
(847) 843-7500
FAX
(847) 843-2798
Phone
(714) 373-7857
FAX
(714) 373-7102
Phone
(803) 448-9411
FAX
(803) 448-1943
Phone
(207) 324-4140
FAX
(207) 324-7223
Phone
(619) 661-6322
FAX
(619) 661-1055
Table 5. Schottky Diode Selection Table
1A Diodes
VR
20V
30V
40V
3A Diodes
Surface
Through
Surface
Through
Mount
Hole
Mount
Hole
SK12
1N5817
SK32
1N5820
B120
SR102
SK13
1N5818
SK33
1N5821
B130
11DQ03
30WQ03F
31DQ03
MBRS130
SR103
SR302
SK14
1N5819
SK34
1N5822
B140
11DQ04
30BQ040
MBR340
MBRS140
SR104
30WQ04F
31DQ04
10BQ040
MBRS340
SR304
10MQ040
MBRD340
15MQ040
50V
SK15
MBR150
SK35
MBR350
B150
11DQ05
30WQ05F
31DQ05
10BQ050
SR105
SR305
Submit Documentation Feedback
Copyright © 2004–2005, Texas Instruments Incorporated
Product Folder Links: LM2675
15
LM2675
SNVS129E – MAY 2004 – REVISED JUNE 2005
www.ti.com
Table 6. Diode Manufacturers' Phone Numbers
International Rectifier Corp.
Motorola, Inc.
General Instruments Corp.
Diodes, Inc.
Phone
(310) 322-3331
FAX
(310) 322-3332
Phone
(800) 521-6274
FAX
(602) 244-6609
Phone
(516) 847-3000
FAX
(516) 847-3236
Phone
(805) 446-4800
FAX
(805) 446-4850
Figure 28. RMS Current Ratings for Low ESR Electrolytic Capacitors (Typical)
Table 7. AVX TPS
Recommended Application Voltage
Voltage Rating
+85°C Rating
3.3
6.3
5
10
10
20
12
25
15
35
Table 8. Sprague 594D
Recommended Application Voltage
Voltage Rating
+85°C Rating
16
2.5
4
3.3
6.3
5
10
8
16
12
20
18
25
24
35
29
50
Submit Documentation Feedback
Copyright © 2004–2005, Texas Instruments Incorporated
Product Folder Links: LM2675
LM2675
www.ti.com
SNVS129E – MAY 2004 – REVISED JUNE 2005
LM2675 Series Buck Regulator Design Procedure (Adjustable Output)
PROCEDURE (Adjustable Output Voltage Version)
EXAMPLE (Adjustable Output Voltage Version)
To simplify the buck regulator design procedure, Texas Instruments
is making available computer design software to be used with the
SIMPLE SWITCHER line of switching regulators.LM267X Made
Simpleversion 6.0 is available for use on Windows®3.1, NT, or 95
operating systems.
Given:
Given:
•
•
•
•
•
•
•
•
VOUT = Regulated Output Voltage
VIN(max) = Maximum Input Voltage
ILOAD(max) = Maximum Load Current
F = Switching Frequency (Fixed at a nominal 260
kHz).
VOUT = 20V
VIN(max) = 28V
ILOAD(max) = 1A
F = Switching Frequency (Fixed at a nominal 260
kHz).
1. Programming Output Voltage (Selecting R1 and R2, as shown in 1. Programming Output Voltage (Selecting R1 and R2, as shown in
Figure 23)
Figure 23)
Use the following formula to select the appropriate resistor values.
Select R1 to be 1 kΩ, 1%. Solve for R2.
where VREF = 1.21V
Select a value for R1 between 240Ω and 1.5 kΩ. The lower resistor
values minimize noise pickup in the sensitive feedback pin. (For the
lowest temperature coefficient and the best stability with time, use
1% metal film resistors.)
R2 = 1k (16.53 − 1) = 15.53 kΩ, closest 1% value is 15.4 kΩ.
R2 = 15.4 kΩ.
2. Inductor Selection (L1)
2. Inductor Selection (L1)
A. Calculate the inductor Volt • microsecond constant E • T (V • μs),
from the following formula:
A. Calculate the inductor Volt • microsecond constant (E • T),
where
•
•
VSAT = internal switch saturation voltage =
0.25V
VD = diode forward voltage drop = 0.5V
B. Use the E • T value from the previous formula and match it with
the E • T number on the vertical axis of the Inductor Value Selection
Guide shown in Figure 27.
B. E • T = 21.6 (V • μs)
C. On the horizontal axis, select the maximum load current.
C. ILOAD(max) = 1A
D. Identify the inductance region intersected by the E • T value and
the Maximum Load Current value. Each region is identified by an
inductance value and an inductor code (LXX).
D. From the inductor value selection guide shown in Figure 27, the
inductance region intersected by the 21.6 (V • μs) horizontal line and
the 1A vertical line is 68 μH, and the inductor code is L30.
E. Select an appropriate inductor from the four manufacturer's part
numbers listed in Table 1. For information on the different types of
inductors, see the inductor selection in the fixed output voltage
design procedure.
E. From the table in Table 1, locate line L30, and select an inductor
part number from the list of manufacturers part numbers.
3. Output Capacitor Selection (COUT)
3. Output Capacitor SeIection (COUT)
A. Select an output capacitor from the capacitor code selection guide A. Use the appropriate row of the capacitor code selection guide, in
in Table 9. Using the inductance value found in the inductor
Table 9. For this example, use the 15–20V row. The capacitor code
selection guide, step 1, locate the appropriate capacitor code
corresponding to an inductance of 68 μH is C20.
corresponding to the desired output voltage.
Submit Documentation Feedback
Copyright © 2004–2005, Texas Instruments Incorporated
Product Folder Links: LM2675
17
LM2675
SNVS129E – MAY 2004 – REVISED JUNE 2005
www.ti.com
PROCEDURE (Adjustable Output Voltage Version)
EXAMPLE (Adjustable Output Voltage Version)
B. Select an appropriate capacitor value and voltage rating, using
the capacitor code, from the output capacitor selection table in
Table 10. There are two solid tantalum (surface mount) capacitor
manufacturers and four electrolytic (through hole) capacitor
manufacturers to choose from. It is recommended that both the
manufacturers and the manufacturer's series that are listed in the
table be used. A table listing the manufacturers' phone numbers is
located in Table 4.
B. From the output capacitor selection table in Table 10, choose a
capacitor value (and voltage rating) that intersects the capacitor
code(s) selected in section A, C20.
The capacitance and voltage rating values corresponding to the
capacitor code C20 are the:
Surface Mount:
33 μF/25V Sprague 594D Series.
33 μF/25V AVX TPS Series.
Through Hole:
33 μF/25V Sanyo OS-CON SC Series.
120 μF/35V Sanyo MV-GX Series.
120 μF/35V Nichicon PL Series.
120 μF/35V Panasonic HFQ Series.
Other manufacturers or other types of capacitors may also be used,
provided the capacitor specifications (especially the 100 kHz ESR)
closely match the characteristics of the capacitors listed in the output
capacitor table. Refer to the capacitor manufacturers' data sheet for
this information.
4. Catch Diode Selection (D1)
A. In normal operation, the average current of the catch diode is the
load current times the catch diode duty cycle, 1-D (D is the switch
duty cycle, which is approximately VOUT/VIN). The largest value of
the catch diode average current occurs at the maximum input
voltage (minimum D). For normal operation, the catch diode current
rating must be at least 1.3 times greater than its maximum average
current. However, if the power supply design must withstand a
continuous output short, the diode should have a current rating
greater than the maximum current limit of the LM2675. The most
stressful condition for this diode is a shorted output condition.
4. Catch Diode Selection (D1)
A. Refer to the table shown in Table 5. Schottky diodes provide the
best performance, and in this example a 1A, 40V Schottky diode
would be a good choice. If the circuit must withstand a continuous
shorted output, a higher current (at least 2.2A) Schottky diode is
recommended.
B. The reverse voltage rating of the diode should be at least 1.25
times the maximum input voltage.
C. Because of their fast switching speed and low forward voltage
drop, Schottky diodes provide the best performance and efficiency.
The Schottky diode must be located close to the LM2675 using short
leads and short printed circuit traces.
5. Input Capacitor (CIN)
A low ESR aluminum or tantalum bypass capacitor is needed
between the input pin and ground to prevent large voltage transients
from appearing at the input. This capacitor should be located close
to the IC using short leads. In addition, the RMS current rating of the
input capacitor should be selected to be at least ½ the DC load
current. The capacitor manufacturer data sheet must be checked to
assure that this current rating is not exceeded. The curves shown in
Figure 28 show typical RMS current ratings for several different
aluminum electrolytic capacitor values. A parallel connection of two
or more capacitors may be required to increase the total minimum
RMS current rating to suit the application requirements.
For an aluminum electrolytic capacitor, the voltage rating should be
at least 1.25 times the maximum input voltage. Caution must be
exercised if solid tantalum capacitors are used. The tantalum
capacitor voltage rating should be twice the maximum input voltage.
Table 7 and Table 8 show the recommended application voltage for
AVX TPS and Sprague 594D tantalum capacitors. It is also
recommended that they be surge current tested by the manufacturer.
The TPS series available from AVX, and the 593D and 594D series
from Sprague are all surge current tested. Another approach to
minimize the surge current stresses on the input capacitor is to add
a small inductor in series with the input supply line.
Use caution when using ceramic capacitors for input bypassing,
because it may cause severe ringing at the VIN pin.
5. Input Capacitor (CIN)
The important parameters for the input capacitor are the input
voltage rating and the RMS current rating. With a maximum input
voltage of 28V, an aluminum electrolytic capacitor with a voltage
rating of at least 35V (1.25 × VIN) would be needed.
The RMS current rating requirement for the input capacitor in a buck
regulator is approximately ½ the DC load current. In this example,
with a 1A load, a capacitor with a RMS current rating of at least 500
mA is needed. The curves shown in Figure 28 can be used to select
an appropriate input capacitor. From the curves, locate the 35V line
and note which capacitor values have RMS current ratings greater
than 500 mA.
For a through hole design, a 330 μF/35V electrolytic capacitor
(Panasonic HFQ series, Nichicon PL, Sanyo MV-GX series or
equivalent) would be adequate. Other types or other manufacturers'
capacitors can be used provided the RMS ripple current ratings are
adequate. Additionally, for a complete surface mount design,
electrolytic capacitors such as the Sanyo CV-C or CV-BS, and the
Nichicon WF or UR and the NIC Components NACZ series could be
considered.
For surface mount designs, solid tantalum capacitors can be used,
but caution must be exercised with regard to the capacitor surge
current rating and voltage rating. In this example, checking Table 8,
and the Sprague 594D series datasheet, a Sprague 594D 15 μF,
50V capacitor is adequate.
6. Boost Capacitor (CB)
6. Boost Capacitor (CB)
This capacitor develops the necessary voltage to turn the switch
gate on fully. All applications should use a 0.01 μF, 50V ceramic
capacitor.
For this application, and all applications, use a 0.01 μF, 50V ceramic
capacitor.
18
Submit Documentation Feedback
Copyright © 2004–2005, Texas Instruments Incorporated
Product Folder Links: LM2675
LM2675
www.ti.com
SNVS129E – MAY 2004 – REVISED JUNE 2005
Table 9. Capacitor Code Selection Guide
(1)
Inductance (μH)
Case
Style (1)
Output
Voltage (V)
22
33
47
SM and TH
1.21–2.50
—
—
SM and TH
2.50–3.75
—
—
SM and TH
3.75–5.0
—
SM and TH
5.0–6.25
—
SM and TH
6.25–7.5
C8
C4
C7
C6
C6
C6
C6
SM and TH
7.5–10.0
C9
C10
C11
C12
C13
C13
C13
SM and TH
10.0–12.5
C14
C11
C12
C12
C13
C13
C13
SM and TH
12.5–15.0
C15
C16
C17
C17
C17
C17
C17
SM and TH
15.0–20.0
C18
C19
C20
C20
C20
C20
C20
SM and TH
20.0–30.0
C21
C22
C22
C22
C22
C22
C22
TH
30.0–37.0
C23
C24
C24
C25
C25
C25
C25
SM - Surface Mount,
68
100
150
220
—
—
C1
C2
C3
—
C1
C2
C3
C3
—
C4
C5
C6
C6
C6
C4
C7
C6
C6
C6
C6
TH - Through Hole
Table 10. Output Capacitor Selection Table
Output Capacitor
Cap.
Ref.
Desg.
#
(1)
(2)
Surface Mount
Through Hole
Sprague
AVX TPS
Sanyo OS-CON
Sanyo MV-GX
Nichicon
Panasonic
594D Series
Series
SA Series
Series
PL Series
HFQ Series
(μF/V)
(μF/V)
(μF/V)
(μF/V)
(μF/V)
(μF/V)
C1
120/6.3
100/10
100/10
220/35
220/35
220/35
C2
120/6.3
100/10
100/10
150/35
150/35
150/35
C3
120/6.3
100/10
100/35
120/35
120/35
120/35
C4
68/10
100/10
68/10
220/35
220/35
220/35
C5
100/16
100/10
100/10
150/35
150/35
150/35
C6
100/16
100/10
100/10
120/35
120/35
120/35
C7
68/10
100/10
68/10
150/35
150/35
150/35
C8
100/16
100/10
100/10
330/35
330/35
330/35
C9
100/16
100/16
100/16
330/35
330/35
330/35
C10
100/16
100/16
68/16
220/35
220/35
220/35
C11
100/16
100/16
68/16
150/35
150/35
150/35
C12
100/16
100/16
68/16
120/35
120/35
120/35
C13
100/16
100/16
100/16
120/35
120/35
120/35
C14
100/16
100/16
100/16
220/35
220/35
220/35
C15
47/20
68/20
47/20
220/35
220/35
220/35
C16
47/20
68/20
47/20
150/35
150/35
150/35
C17
47/20
68/20
47/20
120/35
120/35
120/35
C18
68/25
(2×) 33/25
47/25
(1)
220/35
220/35
220/35
C19
33/25
33/25
33/25
(1)
150/35
150/35
150/35
C20
33/25
33/25
33/25
(1)
120/35
120/35
120/35
C21
33/35
(2×) 22/25
(2)
150/35
150/35
150/35
C22
33/35
22/35
(2)
120/35
120/35
120/35
C23
(2)
(2)
(2)
220/50
100/50
120/50
C24
(2)
(2)
(2)
150/50
100/50
120/50
C25
(2)
(2)
(2)
150/50
82/50
82/50
The SC series of Os-Con capacitors (others are SA series)
The voltage ratings of the surface mount tantalum chip and Os-Con capacitors are too low to work at these voltages.
Submit Documentation Feedback
Copyright © 2004–2005, Texas Instruments Incorporated
Product Folder Links: LM2675
19
LM2675
SNVS129E – MAY 2004 – REVISED JUNE 2005
www.ti.com
APPLICATION INFORMATION
TYPICAL SURFACE MOUNT PC BOARD LAYOUT, FIXED OUTPUT (4X SIZE)
CIN - 15 μF, 50V, Solid Tantalum Sprague, “594D series”
COUT - 68 μF, 16V, Solid Tantalum Sprague, “594D series”
D1 - 1A, 40V Schottky Rectifier, Surface Mount
L1 - 33 μH, L23, Coilcraft DO3316
CB - 0.01 μF, 50V, Ceramic
TYPICAL SURFACE MOUNT PC BOARD LAYOUT, ADJUSTABLE OUTPUT (4X SIZE)
CIN - 15 μF, 50V, Solid Tantalum Sprague, “594D series”
COUT - 33 μF, 25V, Solid Tantalum Sprague, “594D series”
D1 - 1A, 40V Schottky Rectifier, Surface Mount
L1 - 68 μH, L30, Coilcraft DO3316
CB - 0.01 μF, 50V, Ceramic
R1 - 1k, 1%
R2 - Use formula in Design Procedure
Figure 29. PC Board Layout
Layout is very important in switching regulator designs. Rapidly switching currents associated with wiring
inductance can generate voltage transients which can cause problems. For minimal inductance and ground
loops, the wires indicated by heavy lines (in Figure 22 and Figure 23) should be wide printed circuit traces
and should be kept as short as possible. For best results, external components should be located as close to
the switcher IC as possible using ground plane construction or single point grounding.
If open core inductors are used, special care must be taken as to the location and positioning of this type of
inductor. Allowing the inductor flux to intersect sensitive feedback, IC ground path, and COUT wiring can cause
problems.
20
Submit Documentation Feedback
Copyright © 2004–2005, Texas Instruments Incorporated
Product Folder Links: LM2675
LM2675
www.ti.com
SNVS129E – MAY 2004 – REVISED JUNE 2005
When using the adjustable version, special care must be taken as to the location of the feedback resistors and
the associated wiring. Physically locate both resistors near the IC, and route the wiring away from the inductor,
especially an open core type of inductor.
WSON PACKAGE DEVICES
The LM2675 is offered in the 16 lead WSON surface mount package to allow for increased power dissipation
compared to the SOIC and PDIP.
The Die Attach Pad (DAP) can and should be connected to PCB Ground plane/island. For CAD and assembly
guidelines refer to Application Note AN-1187 (SNOA401).
Submit Documentation Feedback
Copyright © 2004–2005, Texas Instruments Incorporated
Product Folder Links: LM2675
21
PACKAGE OPTION ADDENDUM
www.ti.com
16-Aug-2013
PACKAGING INFORMATION
Orderable Device
Status
(1)
Package Type Package Pins Package
Drawing
Qty
Eco Plan
Lead/Ball Finish
(2)
MSL Peak Temp
Op Temp (°C)
Device Marking
(3)
(4/5)
LM2675LD-5.0
ACTIVE
WSON
NHN
16
1000
TBD
Call TI
Call TI
-40 to 125
S000FB
LM2675LD-5.0/NOPB
ACTIVE
WSON
NHN
16
1000
Green (RoHS
& no Sb/Br)
CU SN
Level-3-260C-168 HR
-40 to 125
S000FB
LM2675LD-ADJ
ACTIVE
WSON
NHN
16
1000
TBD
Call TI
Call TI
-40 to 125
S000GB
LM2675LD-ADJ/NOPB
ACTIVE
WSON
NHN
16
1000
Green (RoHS
& no Sb/Br)
CU SN
Level-3-260C-168 HR
-40 to 125
S000GB
LM2675LDX-ADJ
ACTIVE
WSON
NHN
16
4500
TBD
Call TI
Call TI
-40 to 125
S000GB
LM2675LDX-ADJ/NOPB
ACTIVE
WSON
NHN
16
4500
Green (RoHS
& no Sb/Br)
CU SN
Level-3-260C-168 HR
-40 to 125
S000GB
LM2675M-12
ACTIVE
SOIC
D
8
95
TBD
Call TI
Call TI
-40 to 125
2675
M-12
LM2675M-12/NOPB
ACTIVE
SOIC
D
8
95
Green (RoHS
& no Sb/Br)
CU SN
Level-1-260C-UNLIM
-40 to 125
2675
M-12
LM2675M-3.3/NOPB
ACTIVE
SOIC
D
8
95
Green (RoHS
& no Sb/Br)
CU SN
Level-1-260C-UNLIM
-40 to 125
2675
M3.3
LM2675M-5.0
ACTIVE
SOIC
D
8
95
TBD
Call TI
Call TI
-40 to 125
2675
M5.0
LM2675M-5.0/NOPB
ACTIVE
SOIC
D
8
95
Green (RoHS
& no Sb/Br)
CU SN
Level-1-260C-UNLIM
-40 to 125
2675
M5.0
LM2675M-ADJ
ACTIVE
SOIC
D
8
95
TBD
Call TI
Call TI
-40 to 125
2675
MADJ
LM2675M-ADJ/NOPB
ACTIVE
SOIC
D
8
95
Green (RoHS
& no Sb/Br)
CU SN
Level-1-260C-UNLIM
-40 to 125
2675
MADJ
LM2675MX-12
ACTIVE
SOIC
D
8
2500
TBD
Call TI
Call TI
-40 to 125
2675
M-12
LM2675MX-12/NOPB
ACTIVE
SOIC
D
8
2500
Green (RoHS
& no Sb/Br)
CU SN
Level-1-260C-UNLIM
-40 to 125
2675
M-12
LM2675MX-3.3
ACTIVE
SOIC
D
8
2500
TBD
Call TI
Call TI
-40 to 125
2675
M3.3
LM2675MX-3.3/NOPB
ACTIVE
SOIC
D
8
2500
Green (RoHS
& no Sb/Br)
CU SN
Level-1-260C-UNLIM
-40 to 125
2675
M3.3
Addendum-Page 1
Samples
PACKAGE OPTION ADDENDUM
www.ti.com
16-Aug-2013
Orderable Device
Status
(1)
Package Type Package Pins Package
Drawing
Qty
Eco Plan
Lead/Ball Finish
(2)
MSL Peak Temp
Op Temp (°C)
Device Marking
(3)
(4/5)
LM2675MX-5.0/NOPB
ACTIVE
SOIC
D
8
2500
Green (RoHS
& no Sb/Br)
CU SN
Level-1-260C-UNLIM
-40 to 125
2675
M5.0
LM2675MX-ADJ
ACTIVE
SOIC
D
8
2500
TBD
Call TI
Call TI
-40 to 125
2675
MADJ
LM2675MX-ADJ/NOPB
ACTIVE
SOIC
D
8
2500
Green (RoHS
& no Sb/Br)
CU SN
Level-1-260C-UNLIM
-40 to 125
2675
MADJ
LM2675N-12
ACTIVE
PDIP
P
8
40
TBD
Call TI
Call TI
-40 to 125
LM2675
N-12
LM2675N-12/NOPB
ACTIVE
PDIP
P
8
40
Green (RoHS
& no Sb/Br)
CU SN
Level-1-NA-UNLIM
-40 to 125
LM2675
N-12
LM2675N-3.3
ACTIVE
PDIP
P
8
40
TBD
Call TI
Call TI
-40 to 125
LM2675
N-3.3
LM2675N-3.3/NOPB
ACTIVE
PDIP
P
8
40
Green (RoHS
& no Sb/Br)
CU SN
Level-1-NA-UNLIM
-40 to 125
LM2675
N-3.3
LM2675N-5.0
ACTIVE
PDIP
P
8
40
TBD
Call TI
Call TI
-40 to 125
LM2675
N-5.0
LM2675N-5.0/NOPB
ACTIVE
PDIP
P
8
40
Green (RoHS
& no Sb/Br)
CU SN
Level-1-NA-UNLIM
-40 to 125
LM2675
N-5.0
LM2675N-ADJ
ACTIVE
PDIP
P
8
40
TBD
Call TI
Call TI
-40 to 125
LM2675
N-ADJ
LM2675N-ADJ/NOPB
ACTIVE
PDIP
P
8
40
Green (RoHS
& no Sb/Br)
CU SN
Level-1-NA-UNLIM
-40 to 125
LM2675
N-ADJ
(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)
Eco Plan - The planned eco-friendly classification: Pb-Free (RoHS), Pb-Free (RoHS Exempt), or Green (RoHS & no Sb/Br) - please check http://www.ti.com/productcontent for the latest availability
information and additional product content details.
TBD: The Pb-Free/Green conversion plan has not been defined.
Pb-Free (RoHS): TI's terms "Lead-Free" or "Pb-Free" mean semiconductor products that are compatible with the current RoHS requirements for all 6 substances, including the requirement that
lead not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, TI Pb-Free products are suitable for use in specified lead-free processes.
Pb-Free (RoHS Exempt): This component has a RoHS exemption for either 1) lead-based flip-chip solder bumps used between the die and package, or 2) lead-based die adhesive used between
the die and leadframe. The component is otherwise considered Pb-Free (RoHS compatible) as defined above.
Addendum-Page 2
Samples
PACKAGE OPTION ADDENDUM
www.ti.com
16-Aug-2013
Green (RoHS & no Sb/Br): TI defines "Green" to mean Pb-Free (RoHS compatible), and free of Bromine (Br) and Antimony (Sb) based flame retardants (Br or Sb do not exceed 0.1% by weight
in homogeneous material)
(3)
MSL, Peak Temp. -- The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder temperature.
(4)
There may be additional marking, which relates to the logo, the lot trace code information, or the environmental category on the device.
(5)
Multiple Device Markings will be inside parentheses. Only one Device Marking contained in parentheses and separated by a "~" will appear on a device. If a line is indented then it is a continuation
of the previous line and the two combined represent the entire Device Marking for that device.
Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is provided. TI bases its knowledge and belief on information
provided by third parties, and makes no representation or warranty as to the accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and
continues to take reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on incoming materials and chemicals.
TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited information may not be available for release.
In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI to Customer on an annual basis.
Addendum-Page 3
PACKAGE MATERIALS INFORMATION
www.ti.com
26-Mar-2013
TAPE AND REEL INFORMATION
*All dimensions are nominal
Device
Package Package Pins
Type Drawing
SPQ
Reel
Reel
A0
Diameter Width (mm)
(mm) W1 (mm)
B0
(mm)
K0
(mm)
P1
(mm)
W
Pin1
(mm) Quadrant
LM2675LD-5.0
WSON
NHN
16
1000
178.0
12.4
5.3
5.3
1.3
8.0
12.0
Q1
LM2675LD-5.0/NOPB
WSON
NHN
16
1000
178.0
12.4
5.3
5.3
1.3
8.0
12.0
Q1
LM2675LD-ADJ
WSON
NHN
16
1000
178.0
12.4
5.3
5.3
1.3
8.0
12.0
Q1
LM2675LD-ADJ/NOPB
WSON
NHN
16
1000
178.0
12.4
5.3
5.3
1.3
8.0
12.0
Q1
LM2675LDX-ADJ
WSON
NHN
16
4500
330.0
12.4
5.3
5.3
1.3
8.0
12.0
Q1
LM2675LDX-ADJ/NOPB
WSON
NHN
16
4500
330.0
12.4
5.3
5.3
1.3
8.0
12.0
Q1
LM2675MX-12
SOIC
D
8
2500
330.0
12.4
6.5
5.4
2.0
8.0
12.0
Q1
LM2675MX-12/NOPB
SOIC
D
8
2500
330.0
12.4
6.5
5.4
2.0
8.0
12.0
Q1
LM2675MX-3.3
SOIC
D
8
2500
330.0
12.4
6.5
5.4
2.0
8.0
12.0
Q1
LM2675MX-3.3/NOPB
SOIC
D
8
2500
330.0
12.4
6.5
5.4
2.0
8.0
12.0
Q1
LM2675MX-5.0/NOPB
SOIC
D
8
2500
330.0
12.4
6.5
5.4
2.0
8.0
12.0
Q1
LM2675MX-ADJ
SOIC
D
8
2500
330.0
12.4
6.5
5.4
2.0
8.0
12.0
Q1
LM2675MX-ADJ/NOPB
SOIC
D
8
2500
330.0
12.4
6.5
5.4
2.0
8.0
12.0
Q1
Pack Materials-Page 1
PACKAGE MATERIALS INFORMATION
www.ti.com
26-Mar-2013
*All dimensions are nominal
Device
Package Type
Package Drawing
Pins
SPQ
Length (mm)
Width (mm)
Height (mm)
LM2675LD-5.0
WSON
NHN
16
1000
210.0
185.0
35.0
LM2675LD-5.0/NOPB
WSON
NHN
16
1000
213.0
191.0
55.0
LM2675LD-ADJ
WSON
NHN
16
1000
210.0
185.0
35.0
LM2675LD-ADJ/NOPB
WSON
NHN
16
1000
213.0
191.0
55.0
LM2675LDX-ADJ
WSON
NHN
16
4500
367.0
367.0
35.0
LM2675LDX-ADJ/NOPB
WSON
NHN
16
4500
367.0
367.0
35.0
LM2675MX-12
SOIC
D
8
2500
367.0
367.0
35.0
LM2675MX-12/NOPB
SOIC
D
8
2500
367.0
367.0
35.0
LM2675MX-3.3
SOIC
D
8
2500
367.0
367.0
35.0
LM2675MX-3.3/NOPB
SOIC
D
8
2500
367.0
367.0
35.0
LM2675MX-5.0/NOPB
SOIC
D
8
2500
367.0
367.0
35.0
LM2675MX-ADJ
SOIC
D
8
2500
367.0
367.0
35.0
LM2675MX-ADJ/NOPB
SOIC
D
8
2500
367.0
367.0
35.0
Pack Materials-Page 2
MECHANICAL DATA
NHN0016A
LDA16A (REV A)
www.ti.com
IMPORTANT NOTICE
Texas Instruments Incorporated and its subsidiaries (TI) reserve the right to make corrections, enhancements, improvements and other
changes to its semiconductor products and services per JESD46, latest issue, and to discontinue any product or service per JESD48, latest
issue. Buyers should obtain the latest relevant information before placing orders and should verify that such information is current and
complete. All semiconductor products (also referred to herein as “components”) are sold subject to TI’s terms and conditions of sale
supplied at the time of order acknowledgment.
TI warrants performance of its components to the specifications applicable at the time of sale, in accordance with the warranty in TI’s terms
and conditions of sale of semiconductor products. Testing and other quality control techniques are used to the extent TI deems necessary
to support this warranty. Except where mandated by applicable law, testing of all parameters of each component is not necessarily
performed.
TI assumes no liability for applications assistance or the design of Buyers’ products. Buyers are responsible for their products and
applications using TI components. To minimize the risks associated with Buyers’ products and applications, Buyers should provide
adequate design and operating safeguards.
TI does not warrant or represent that any license, either express or implied, is granted under any patent right, copyright, mask work right, or
other intellectual property right relating to any combination, machine, or process in which TI components or services are used. Information
published by TI regarding third-party products or services does not constitute a license to use such products or services or a warranty or
endorsement thereof. Use of such information may require a license from a third party under the patents or other intellectual property of the
third party, or a license from TI under the patents or other intellectual property of TI.
Reproduction of significant portions of TI information in TI data books or data sheets is permissible only if reproduction is without alteration
and is accompanied by all associated warranties, conditions, limitations, and notices. TI is not responsible or liable for such altered
documentation. Information of third parties may be subject to additional restrictions.
Resale of TI components or services with statements different from or beyond the parameters stated by TI for that component or service
voids all express and any implied warranties for the associated TI component or service and is an unfair and deceptive business practice.
TI is not responsible or liable for any such statements.
Buyer acknowledges and agrees that it is solely responsible for compliance with all legal, regulatory and safety-related requirements
concerning its products, and any use of TI components in its applications, notwithstanding any applications-related information or support
that may be provided by TI. Buyer represents and agrees that it has all the necessary expertise to create and implement safeguards which
anticipate dangerous consequences of failures, monitor failures and their consequences, lessen the likelihood of failures that might cause
harm and take appropriate remedial actions. Buyer will fully indemnify TI and its representatives against any damages arising out of the use
of any TI components in safety-critical applications.
In some cases, TI components may be promoted specifically to facilitate safety-related applications. With such components, TI’s goal is to
help enable customers to design and create their own end-product solutions that meet applicable functional safety standards and
requirements. Nonetheless, such components are subject to these terms.
No TI components are authorized for use in FDA Class III (or similar life-critical medical equipment) unless authorized officers of the parties
have executed a special agreement specifically governing such use.
Only those TI components which TI has specifically designated as military grade or “enhanced plastic” are designed and intended for use in
military/aerospace applications or environments. Buyer acknowledges and agrees that any military or aerospace use of TI components
which have not been so designated is solely at the Buyer's risk, and that Buyer is solely responsible for compliance with all legal and
regulatory requirements in connection with such use.
TI has specifically designated certain components as meeting ISO/TS16949 requirements, mainly for automotive use. In any case of use of
non-designated products, TI will not be responsible for any failure to meet ISO/TS16949.
Products
Applications
Audio
www.ti.com/audio
Automotive and Transportation
www.ti.com/automotive
Amplifiers
amplifier.ti.com
Communications and Telecom
www.ti.com/communications
Data Converters
dataconverter.ti.com
Computers and Peripherals
www.ti.com/computers
DLP® Products
www.dlp.com
Consumer Electronics
www.ti.com/consumer-apps
DSP
dsp.ti.com
Energy and Lighting
www.ti.com/energy
Clocks and Timers
www.ti.com/clocks
Industrial
www.ti.com/industrial
Interface
interface.ti.com
Medical
www.ti.com/medical
Logic
logic.ti.com
Security
www.ti.com/security
Power Mgmt
power.ti.com
Space, Avionics and Defense
www.ti.com/space-avionics-defense
Microcontrollers
microcontroller.ti.com
Video and Imaging
www.ti.com/video
RFID
www.ti-rfid.com
OMAP Applications Processors
www.ti.com/omap
TI E2E Community
e2e.ti.com
Wireless Connectivity
www.ti.com/wirelessconnectivity
Mailing Address: Texas Instruments, Post Office Box 655303, Dallas, Texas 75265
Copyright © 2013, Texas Instruments Incorporated