January 2007
LM2940/LM2940C
1A Low Dropout Regulator
General Description
The LM2940/LM2940C positive voltage regulator features the
ability to source 1A of output current with a dropout voltage of
typically 0.5V and a maximum of 1V over the entire temper-
ature range. Furthermore, a quiescent current reduction cir-
cuit has been included which reduces the ground current
when the differential between the input voltage and the output
voltage exceeds approximately 3V. The quiescent current
with 1A of output current and an input-output differential of 5V
is therefore only 30 mA. Higher quiescent currents only exist
when the regulator is in the dropout mode (VIN − VOUT 3V).
Designed also for vehicular applications, the LM2940/
LM2940C and all regulated circuitry are protected from re-
verse battery installations or 2-battery jumps. During line
transients, such as load dump when the input voltage can
momentarily exceed the specified maximum operating volt-
age, the regulator will automatically shut down to protect both
the internal circuits and the load. The LM2940/LM2940C can-
not be harmed by temporary mirror-image insertion. Familiar
regulator features such as short circuit and thermal overload
protection are also provided.
Features
Dropout voltage typically 0.5V @IO = 1A
Output current in excess of 1A
Output voltage trimmed before assembly
Reverse battery protection
Internal short circuit current limit
Mirror image insertion protection
P+ Product Enhancement tested
Typical Application
882203
*Required if regulator is located far from power supply filter.
**COUT must be at least 22 μF to maintain stability. May be increased without bound to maintain regulation during transients. Locate as close as possible to
the regulator. This capacitor must be rated over the same operating temperature range as the regulator and the ESR is critical; see curve.
Ordering Information
Temp
Range
Output Voltage Package
5.0 8.0 9.0 10 12 15
0°C
TJ
125°C
LM2940CT-5.0 LM2940CT-9.0 LM2940CT-12 LM2940CT-15 TO-220
LM2940CS-5.0 LM2940CS-9.0 LM2940CS-12 LM2940CS-15
TO-263
LM2940CSX
-5.0 LM2940CSX
-9.0 LM2940CSX
-12
LM2940CSX
-15
−40°C
TJ
125°C
LM2940LD-5.0 LM2940LD-8.0 LM2940LD-9.0 LM2940LD-10 LM2940LD-12 LM2940LD-15
LLP
1k Units
Tape and
Reel
LM2940LDX
-5.0
LM2940LDX
-8.0
LM2940LDX
-9.0
LM2940LDX
-10
LM2940LDX
-12
LM2940LDX
-15
LLP
4.5k
Units
Tape and
Reel
−40°C
TJ
125°C
LM2940T-5.0 LM2940T-8.0 LM2940T-9.0 LM2940T-10 LM2940T-12 TO-220
LM2940S-5.0 LM2940S-8.0 LM2940S-9.0 LM2940S-10 LM2940S-12 TO-263
LM2940SX-5.0 LM2940SX-8.0 LM2940SX-9.0 LM2940SX-10 LM2940SX-12
© 2007 National Semiconductor Corporation 8822 www.national.com
LM2940/LM2940C 1A Low Dropout Regulator
Temp
Range
Output Voltage Package
5.0 8.0 9.0 10 12 15
−40°C
TA
85°C
LM2940IMP-5.0 LM2940IMP-8.0 LM2940IMP-9.0 LM2940IMP-10 LM2940IMP-12 LM2940IMP-15 SOT-223
LM2940IMPX
-5.0
LM2940IMPX
-8.0
LM2940IMPX
-9.0
LM2940IMPX
-10
LM2940IMPX
-12
LM2940IMPX
-15
SOT-223
in Tape
and Reel
Marking L53B L54B L0EB L55B L56B L70B
The physical size of the SOT-223 is too small to contain the full device part number. The package markings indicated are what will appear on the actual device.
Mil-Aero Ordering Information
Temperature
Range
Output Voltage Package
5.0 8.0 12 15
−55°C
TJ
125°C
LM2940J-5.0/883
5962-8958701EA LM2940J-12/883
5962-9088401QEA
LM2940J-15/883
5962-9088501QEA J16A
LM2940WG5.0/883
5962-8958701XA LM2940WG5-12/883 LM2940WG5-15/883 WG16A
For information on military temperature range products, please go to the Mil/Aero Web Site at http://www.national.com/appinfo/milaero/index.html.
Connection Diagrams
TO-220 (T) Plastic Package
882202
Front View
See NS Package Number TO3B
SOT-223 (MP) 3-Lead
882242
Front View
See NS Package Number MP04A
16-Lead Dual-in-Line Package (J)
882243
Top View
See NS Package Number J16A
16-Lead Ceramic Surface-Mount Package (WG)
882244
Top View
See NS Package Number WG16A
TO-263 (S) Surface-Mount Package
882211
Top View
LLP (LD) 8-Lead
882246
Pin 2 and pin 7 are fused to center DAP
Pin 5 and 6 need to be tied together on PCB board
Top View
See NS Package Number LDC08A
882212
Side View
See NS Package Number TS3B
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LM2940/LM2940C
Absolute Maximum Ratings (Note 1)
If Military/Aerospace specified devices are required,
please contact the National Semiconductor Sales Office/
Distributors for availability and specifications.
LM2940S, J, WG, T, MP 100
ms 60V
LM2940CS, T 1 ms 45V
Internal Power Dissipation
(Note 2) Internally Limited
Maximum Junction Temperature 150°C
Storage Temperature Range −65°C TJ +150°C
Soldering Temperature (Note 3)
TO-220 (T), Wave 260°C, 10s
TO-263 (S) 235°C, 30s
SOT-223 (MP) 260°C, 30s
LLP-8 (LD) 235°C, 30s
ESD Susceptibility (Note 4) 2 kV
Operating Conditions (Note 1)
Input Voltage 26V
Temperature Range
LM2940T, LM2940S −40°C TJ 125°C
LM2940CT, LM2940CS 0°C TJ 125°C
LM2940IMP −40°C TA 85°C
LM2940J, LM2940WG −55°C TJ 125°C
LM2940LD −40°C TJ 125°C
Electrical Characteristics
VIN = VO + 5V, IO = 1A, CO = 22 μF, unless otherwise specified. Boldface limits apply over the entire operating temperature
range of the indicated device. All other specifications apply for TA = TJ = 25°C.
Output Voltage (VO) 5V 8V
Units
LM2940 LM2940/883 LM2940 LM2940/883
Parameter Conditions Typ Limit Limit Typ Limit Limit
(Note 5) (Note 6) (Note 5) (Note 6)
6.25V VIN 26V 9.4V VIN 26V
Output Voltage 5 mA IO 1A 5.00 4.85/4.75 4.85/4.75 8.00 7.76/7.60 7.76/7.60 VMIN
5.15/5.25 5.15/5.25 8.24/8.40 8.24/8.40 VMAX
Line Regulation VO + 2V VIN 26V, 20 50 40/50 20 80 50/80 mVMAX
IO = 5 mA
Load Regulation 50 mA IO 1A
LM2940, LM2940/883 35 50/80 50/100 55 80/130 80/130 mVMAX
LM2940C 35 50 55 80
Output 100 mADC and
Impedance 20 mArms, 35 1000/1000 55 1000/1000 mΩ
fO = 120 Hz
Quiescent VO +2V VIN 26V,
Current IO = 5 mA
LM2940, LM2940/883 10 15/20 15/20 10 15/20 15/20 mAMAX
LM2940C 10 15
VIN = VO + 5V, 30 45/60 50/60 30 45/60 50/60 mAMAX
IO = 1A
Output Noise 10 Hz − 100 kHz, 150 700/700 240 1000/1000 μVrms
Voltage IO = 5 mA
Ripple Rejection fO = 120 Hz, 1 Vrms,
IO = 100 mA
LM2940 72 60/54 66 54/48 dBMIN
LM2940C 72 60 66 54
fO = 1 kHz, 1 Vrms, 60/50 54/48 dBMIN
IO = 5 mA
Long Term 20 32 mV/
Stability 1000 Hr
Dropout Voltage IO = 1A 0.5 0.8/1.0 0.7/1.0 0.5 0.8/1.0 0.7/1.0 VMAX
IO = 100 mA 110 150/200 150/200 110 150/200 150/200 mVMAX
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LM2940/LM2940C
Output Voltage (VO) 5V 8V
Units
LM2940 LM2940/883 LM2940 LM2940/883
Parameter Conditions Typ Limit Limit Typ Limit Limit
(Note 5) (Note 6) (Note 5) (Note 6)
Short Circuit
Current
(Note 7) 1.9 1.6 1.5/1.3 1.9 1.6 1.6/1.3 AMIN
Maximum Line RO = 100Ω
VMIN
Transient LM2940, T 100 ms 75 60/60 75 60/60
LM2940/883, T 20 ms 40/40 40/40
LM2940C, T 1 ms 55 45 55 45
Reverse Polarity RO = 100Ω
DC Input Voltage LM2940, LM2940/883 −30 −15/−15 −15/−15 −30 −15/−15 −15/−15 VMIN
LM2940C −30 −15 −30 −15
Reverse Polarity RO = 100Ω
Transient Input LM2940, T 100 ms −75 −50/−50 −75 −50/−50 VMIN
Voltage LM2940/883, T 20 ms −45/−45 −45/−45
LM2940C, T 1 ms −55 −45/−45
Electrical Characteristics
VIN = VO + 5V, IO = 1A, CO = 22 μF, unless otherwise specified. Boldface limits apply over the entire operating temperature
range of the indicated device. All other specifications apply for TA = TJ = 25°C.
Output Voltage (VO) 9V 10V
Units
Parameter Conditions Typ
LM2940
Typ
LM2940
Limit Limit
(Note 5) (Note 5)
10.5V VIN 26V 11.5V VIN 26V
Output Voltage 5 mA IO 1A 9.00 8.73/8.55 10.00 9.70/9.50 VMIN
9.27/9.45 10.30/10.50 VMAX
Line Regulation VO + 2V VIN 26V, 20 90 20 100 mVMAX
IO = 5 mA
Load Regulation 50 mA IO 1A
LM2940 60 90/150 65 100/165 mVMAX
LM2940C 60 90
Output Impedance 100 mADC and
20 mArms, 60 65 mΩ
fO = 120 Hz
Quiescent VO +2V VIN < 26V,
Current IO = 5 mA
LM2940 10 15/20 10 15/20 mAMAX
LM2940C 10 15
VIN = VO + 5V, IO = 1A 30 45/60 30 45/60 mAMAX
Output Noise 10 Hz − 100 kHz, 270 300 μVrms
Voltage IO = 5 mA
Ripple Rejection fO = 120 Hz, 1 Vrms,
IO = 100 mA
LM2940 64 52/46 63 51/45 dBMIN
LM2940C 64 52
Long Term
Stability
34 36 mV/
1000 Hr
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LM2940/LM2940C
Output Voltage (VO) 9V 10V
Units
Parameter Conditions Typ
LM2940
Typ
LM2940
Limit Limit
(Note 5) (Note 5)
Dropout Voltage IO = 1A 0.5 0.8/1.0 0.5 0.8/1.0 VMAX
IO = 100 mA 110 150/200 110 150/200 mVMAX
Short Circuit (Note 7) 1.9 1.6 1.9 1.6 AMIN
Current
Maximum Line RO = 100Ω
Transient T 100 ms
LM2940 75 60/60 75 60/60 VMIN
LM2940C 55 45
Reverse Polarity RO = 100Ω
DC Input Voltage LM2940 −30 −15/−15 −30 −15/−15 VMIN
LM2940C −30 −15
Reverse Polarity RO = 100Ω
Transient Input T 100 ms
Voltage LM2940 −75 −50/−50 −75 −50/−50 VMIN
LM2940C −55 −45/−45
Electrical Characteristics
VIN = VO + 5V, IO = 1A, CO = 22 μF, unless otherwise specified. Boldface limits apply over the entire operating temperature
range of the indicated device. All other specifications apply for TA = TJ = 25°C.
Output Voltage (VO) 12V 15V
Units
LM2940 LM2940/833 LM2940 LM2940/833
Parameter Conditions Typ Limit Limit Typ Limit Limit
(Note 5) (Note 6) (Note 5) (Note 6)
13.6V VIN 26V 16.75V VIN 26V
Output Voltage 5 mA IO 1A 12.00 11.64/11.40 11.64/11.40 15.00 14.55/14.25 14.55/14.25 VMIN
12.36/12.60 12.36/12.60 15.45/15.75 15.45/15.75 VMAX
Line Regulation VO + 2V VIN 26V, 20 120 75/120 20 150 95/150 mVMAX
IO = 5 mA
Load Regulation 50 mA IO 1A
LM2940, LM2940/883 55 120/200 120/190 150/240 mVMAX
LM2940C 55 120 70 150
Output 100 mADC and
Impedance 20 mArms, 80 1000/1000 100 1000/1000 mΩ
fO = 120 Hz
Quiescent
Current
VO +2V VIN 26V,
IO = 5 mA
LM2940, LM2940/883 10 15/20 15/20 15/20 mAMAX
LM2940C 10 15 10 15
VIN = VO + 5V, IO = 1A 30 45/60 50/60 30 45/60 50/60 mAMAX
Output Noise 10 Hz − 100 kHz, 360 1000/1000 450 1000/1000 μVrms
Voltage IO = 5 mA
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LM2940/LM2940C
Output Voltage (VO) 12V 15V
Units
LM2940 LM2940/833 LM2940 LM2940/833
Parameter Conditions Typ Limit Limit Typ Limit Limit
(Note 5) (Note 6) (Note 5) (Note 6)
Ripple Rejection fO = 120 Hz, 1 Vrms,
IO = 100 mA
LM2940 66 54/48 dBMIN
LM2940C 66 54 64 52
fO = 1 kHz, 1 Vrms, 52/46 48/42 dBMIN
IO = 5 mA
Long Term 48 60 mV/
Stability 1000 Hr
Dropout Voltage IO = 1A 0.5 0.8/1.0 0.7/1.0 0.5 0.8/1.0 0.7/1.0 VMAX
IO = 100 mA 110 150/200 150/200 110 150/200 150/200 mVMAX
Short Circuit (Note 7) 1.9 1.6 1.6/1.3 1.9 1.6 1.6/1.3 AMIN
Current
Maximum Line RO = 100Ω
Transient LM2940, T 100 ms 75 60/60
LM2940/883, T 20 ms 40/40 40/40 VMIN
LM2940C, T 1 ms 55 45 55 45
Reverse Polarity RO = 100Ω
DC Input LM2940, LM2940/883 −30 −15/−15 −15/−15 −15/−15 VMIN
Voltage LM2940C −30 −15 −30 −15
Reverse Polarity RO = 100Ω
Transient Input LM2940, T 100 ms −75 −50/−50
Voltage LM2940/883, T 20 ms −45/−45 −45/−45 VMIN
LM2940C, T 1 ms −55 −45/−45 −55 −45/−45
Thermal Performance
Thermal Resistance
Junction-to-Case, θ(JC)
3-Lead TO-220 4 °C/W
3-Lead TO-263 4
Thermal Resistance
Junction-to-Ambient, θ(JA)
3-Lead TO-220 (Note 2) 60
°C/W
3-Lead TO-263 (Note 2) 80
SOT-223(Note 2) 174
8-Lead LLP (Note 2) 35
Note 1: Absolute Maximum Ratings are limits beyond which damage to the device may occur. Operating Conditions are conditions under which the device
functions but the specifications might not be guaranteed. For guaranteed specifications and test conditions see the Electrical Characteristics.
Note 2: The maximum allowable power dissipation is a function of the maximum junction temperature, TJ, the junction-to-ambient thermal resistance, θJA, and
the ambient temperature, TA. Exceeding the maximum allowable power dissipation will cause excessive die temperature, and the regulator will go into thermal
shutdown. The value of θJA (for devices in still air with no heatsink) is 60°C/W for the TO-220 package, 80°C/W for the TO-263 package, and 174°C/W for the
SOT-223 package. The effective value of θJA can be reduced by using a heatsink (see Application Hints for specific information on heatsinking). The value of
θJA for the LLP 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 LLP package, refer to Application Note AN-1187. It is recommended that 6 vias be placed under the center pad to improve thermal
performance.
Note 3: Refer to JEDEC J-STD-020C for surface mount device (SMD) package reflow profiles and conditions. Unless otherwise stated, the temperature and time
are for Sn-Pb (STD) only.
Note 4: ESD rating is based on the human body model, 100 pF discharged through 1.5 kΩ.
Note 5: All limits are guaranteed at TA = TJ = 25°C only (standard typeface) or over the entire operating temperature range of the indicated device (boldface type).
All limits at TA = TJ = 25°C are 100% production tested. All limits at temperature extremes are guaranteed via correlation using standard Statistical Quality Control
methods.
Note 6: All limits are guaranteed at TA = TJ = 25°C only (standard typeface) or over the entire operating temperature range of the indicated device (boldface type).
All limits are 100% production tested and are used to calculate Outgoing Quality Levels.
Note 7: Output current will decrease with increasing temperature but will not drop below 1A at the maximum specified temperature.
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LM2940/LM2940C
Typical Performance Characteristics
Dropout Voltage
882213
Dropout Voltage vs. Temperature
882214
Output Voltage vs. Temperature
882215
Quiescent Current vs. Temperature
882216
Quiescent Current
882217
Quiescent Current
882218
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LM2940/LM2940C
Line Transient Response
882219
Load Transient Response
882220
Ripple Rejection
882221
Low Voltage Behavior
882225
Low Voltage Behavior
882226
Low Voltage Behavior
882227
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LM2940/LM2940C
Low Voltage Behavior
882228
Low Voltage Behavior
882229
Low Voltage Behavior
882230
Output at Voltage Extremes
882231
Output at Voltage Extremes
882232
Output at Voltage Extremes
882233
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LM2940/LM2940C
Output at Voltage Extremes
882234
Output at Voltage Extremes
882235
Output at Voltage Extremes
882236
Output Capacitor ESR
882206
Peak Output Current
882208
Output Impedance
882222
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LM2940/LM2940C
Maximum Power Dissipation (TO-220)
882223
Maximum Power Dissipation (SOT-223)
882224
Maximum Power Dissipation (TO-263)
882210
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LM2940/LM2940C
Equivalent Schematic Diagram
882201
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LM2940/LM2940C
Application Information
EXTERNAL CAPACITORS
The output capacitor is critical to maintaining regulator stabil-
ity, and must meet the required conditions for both ESR
(Equivalent Series Resistance) and minimum amount of ca-
pacitance.
MINIMUM CAPACITANCE:
The minimum output capacitance required to maintain stabil-
ity is 22 μF (this value may be increased without limit). Larger
values of output capacitance will give improved transient re-
sponse.
ESR LIMITS:
The ESR of the output capacitor will cause loop instability if it
is too high or too low. The acceptable range of ESR plotted
versus load current is shown in the graph below. It is essen-
tial that the output capacitor meet these requirements, or
oscillations can result.
Output Capacitor ESR
882206
FIGURE 1. ESR Limits
It is important to note that for most capacitors, ESR is speci-
fied only at room temperature. However, the designer must
ensure that the ESR will stay inside the limits shown over the
entire operating temperature range for the design.
For aluminum electrolytic capacitors, ESR will increase by
about 30X as the temperature is reduced from 25°C to −40°
C. This type of capacitor is not well-suited for low temperature
operation.
Solid tantalum capacitors have a more stable ESR over tem-
perature, but are more expensive than aluminum electrolyt-
ics. A cost-effective approach sometimes used is to parallel
an aluminum electrolytic with a solid Tantalum, with the total
capacitance split about 75/25% with the Aluminum being the
larger value.
If two capacitors are paralleled, the effective ESR is the par-
allel of the two individual values. The “flatter” ESR of the
Tantalum will keep the effective ESR from rising as quickly at
low temperatures.
HEATSINKING
A heatsink may be required depending on the maximum pow-
er dissipation and maximum ambient temperature of the ap-
plication. Under all possible operating conditions, the junction
temperature must be within the range specified under Abso-
lute Maximum Ratings.
To determine if a heatsink is required, the power dissipated
by the regulator, PD, must be calculated.
The figure below shows the voltages and currents which are
present in the circuit, as well as the formula for calculating the
power dissipated in the regulator:
882237
IIN = IL + IG
PD = (VIN − VOUT) IL + (VIN) IG
FIGURE 2. Power Dissipation Diagram
The next parameter which must be calculated is the maximum
allowable temperature rise, TR(MAX). This is calculated by us-
ing the formula:
TR(MAX) = TJ(MAX) − TA(MAX)
where: TJ(MAX) is the maximum allowable junction tempera-
ture, which is 125°C for commercial grade
parts.
TA(MAX) is the maximum ambient temperature which
will be encountered in the application.
Using the calculated values for TR(MAX) and PD, the maximum
allowable value for the junction-to-ambient thermal resis-
tance, θ(JA), can now be found:
θ(JA) = TR(MAX) / PD
IMPORTANT: If the maximum allowable value for θ(JA) is
found to be 53°C/W for the TO-220 package, 80°C/W for
the TO-263 package, or 174°C/W for the SOT-223 pack-
age, no heatsink is needed since the package alone will
dissipate enough heat to satisfy these requirements.
If the calculated value for θ(JA)falls below these limits, a
heatsink is required.
HEATSINKING TO-220 PACKAGE PARTS
The TO-220 can be attached to a typical heatsink, or secured
to a copper plane on a PC board. If a copper plane is to be
used, the values of θ(JA) will be the same as shown in the next
section for the TO-263.
If a manufactured heatsink is to be selected, the value of
heatsink-to-ambient thermal resistance, θ(H−A), must first be
calculated:
θ(H−A) = θ(JA) − θ(C−H) − θ(J−C)
Where: θ(J−C) is defined as the thermal resistance from the
junction to the surface of the case. A value of
3°C/W can be assumed for θ(J−C) for this cal-
culation.
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LM2940/LM2940C
   θ(C−H) is defined as the thermal resistance between
the case and the surface of the heatsink. The
value of θ(C−H) will vary from about 1.5°C/W to
about 2.5°C/W (depending on method of at-
tachment, insulator, etc.). If the exact value is
unknown, 2°C/W should be assumed for θ(C
−H).
When a value for θ(H−A) is found using the equation shown, a
heatsink must be selected that has a value that is less than
or equal to this number.
θ(H−A) is specified numerically by the heatsink manufacturer
in the catalog, or shown in a curve that plots temperature rise
vs power dissipation for the heatsink.
HEATSINKING TO-263 PACKAGE PARTS
The TO-263 (“S”) package uses a copper plane on the PCB
and the PCB itself as a heatsink. To optimize the heat sinking
ability of the plane and PCB, solder the tab of the package to
the plane.
Figure 3 shows for the TO-263 the measured values of θ(JA)
for different copper area sizes using a typical PCB with 1
ounce copper and no solder mask over the copper area used
for heatsinking.
882238
FIGURE 3. θ(JA) vs. Copper (1 ounce) Area for the TO-263
Package
As shown in the figure, increasing the copper area beyond 1
square inch produces very little improvement. It should also
be observed that the minimum value of θ(JA) for the TO-263
package mounted to a PCB is 32°C/W.
As a design aid, Figure 4 shows the maximum allowable pow-
er dissipation compared to ambient temperature for the
TO-263 device. This assumes a θ(JA) of 35°C/W for 1 square
inch of 1 ounce copper and a maximum junction temperature
(TJ) of 125°C.
882239
FIGURE 4. Maximum Power Dissipation vs. TA for the
TO-263 Package
HEATSINKING SOT-223 PACKAGE PARTS
The SOT-223 (“MP”) packages use a copper plane on the
PCB and the PCB itself as a heatsink. To optimize the heat
sinking ability of the plane and PCB, solder the tab of the
package to the plane.
Figure 5 and Figure 6 show the information for the SOT-223
package. Figure 6 assumes a θ(JA) of 74°C/W for 1 square
inch of 1 ounce copper and 51°C/W for 1 square inch of 2
ounce copper, with a maximum ambient temperature (TA) of
85°C and a maximum junction temperature (TJ) of 125°C.
For techniques for improving the thermal resistance and pow-
er dissipation for the SOT-223 package, please refer to Ap-
plication Note AN-1028.
882240
FIGURE 5. θ(JA) vs. Copper (2 ounce) Area for the SOT-223
Package
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LM2940/LM2940C
882241
FIGURE 6. Maximum Power Dissipation vs. TA for the
SOT-223 Package
HEATSINKING LLP PACKAGE PARTS
The value of θJA for the LLP package is specifically dependent
on PCB trace area, trace material, and the number of layers
and thermal vias. It is recommended that a minimum of 6
thermal vias be placed under the center pad to improve ther-
mal performance.
For techniques for improving the thermal resistance and pow-
er dissipation for the LLP package, please refer to Application
Note AN-1187.
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LM2940/LM2940C
Physical Dimensions inches (millimeters) unless otherwise noted
3-Lead SOT-223 Package
NS Package Number MP04A
16 Lead Dual-in-Line Package (J)
See NS Package Number J16A
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LM2940/LM2940C
16 Lead Surface Mount Package (WG)
See NS Package Number WG16A
3-Lead TO-220 Plastic Package (T)
NS Package Number TO3B
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LM2940/LM2940C
3-Lead TO-263 Surface Mount Package (MP)
NS Package Number TS3B
8-Lead LLP
Order Number LM2940LD-5.0, LM2940LD-8.0,
LM2940LD-9.0, LM2940LD-10,
LM2940LD-12 or LM2940LD-15
NS Package Number LDC08A
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LM2940/LM2940C
Notes
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LM2940/LM2940C
Notes
LM2940/LM2940C 1A Low Dropout Regulator
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NATIONAL’S PRODUCT WARRANTY. EXCEPT WHERE MANDATED BY GOVERNMENT REQUIREMENTS, TESTING OF ALL
PARAMETERS OF EACH PRODUCT IS NOT NECESSARILY PERFORMED. NATIONAL ASSUMES NO LIABILITY FOR
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NATIONAL COMPONENTS, BUYERS SHOULD PROVIDE ADEQUATE DESIGN, TESTING AND OPERATING SAFEGUARDS.
EXCEPT AS PROVIDED IN NATIONAL’S TERMS AND CONDITIONS OF SALE FOR SUCH PRODUCTS, NATIONAL ASSUMES NO
LIABILITY WHATSOEVER, AND NATIONAL DISCLAIMS ANY EXPRESS OR IMPLIED WARRANTY RELATING TO THE SALE
AND/OR USE OF NATIONAL PRODUCTS INCLUDING LIABILITY OR WARRANTIES RELATING TO FITNESS FOR A PARTICULAR
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LIFE SUPPORT POLICY
NATIONAL’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR
SYSTEMS WITHOUT THE EXPRESS PRIOR WRITTEN APPROVAL OF THE CHIEF EXECUTIVE OFFICER AND GENERAL
COUNSEL OF NATIONAL SEMICONDUCTOR CORPORATION. As used herein:
Life support devices or systems are devices 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. A critical component is any component in 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.
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Copyright© 2007 National Semiconductor Corporation
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