NSC 5962-8958701EA

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
temperature range. Furthermore, a quiescent current reduction circuit 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 reverse battery installations or 2-battery jumps. During line
transients, such as load dump when the input voltage can
momentarily exceed the specified maximum operating voltage, the regulator will automatically shut down to protect
both the internal circuits and the load. The LM2940/
LM2940C cannot be harmed by temporary mirror-image insertion. Familiar regulator features such as short circuit and
thermal overload protection are also provided.
Features
n
n
n
n
n
n
n
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
DS008822-3
*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
Temperature
Range
5.0
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
−40˚C ≤ TJ ≤ 125˚C
−40˚C ≤ TJ ≤ 85˚C
Output Voltage
8.0
9.0
10
12
Package
15
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
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
SOT-223 Package
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.
Temperature
Output Voltage
Package
Range
5.0
8.0
12
15
−55˚C ≤ TJ ≤ 125˚C
LM2940J-5.0/883
5962-8958701EA
LM2940J-8.0/883
5962-9088301QEA
LM2940J-12/883
5962-9088401QEA
LM2940J-15/883
5962-9088501QEA
J16A
LM2940WG5.0/883
5962-8958701XA
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.
© 2000 National Semiconductor Corporation
DS008822
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LM2940/LM2940C 1A Low Dropout Regulator
March 2000
LM2940/LM2940C
Connection Diagrams
(TO-220) Plastic Package
3-Lead SOT-223
DS008822-2
DS008822-42
Front View
Order Number LM2940CT-5.0, LM2940CT-9.0,
LM2940CT-12, LM2940CT-15, LM2940T-5.0,
LM2940T-8.0, LM2940T-9.0,
LM2940T-10 or LM2940T-12
See NS Package Number TO3B
Front View
Order Part Number LM2940IMP-5.0,
LM2940IMP-8.0, LM2940IMP-9.0,
LM2940IMP-10, LM2940IMP-12 or LM2940IMP-15
See NS Package Number MP04A
16-Lead Dual-in-Line Package (J)
16-Lead Ceramic Surface-Mount Package (WG)
DS008822-43
DS008822-44
Top View
Order Number LM2940J-5.0/883 (5962-8958701EA),
LM2940J-8.0/883 (5962-9088301QEA),
LM2940J-12/883 (5962-9088401QEA),
LM2940J-15/883 (5962-9088501QEA)
See NS Package Number J16A
Top View
Order Number LM2940WG5.0/883 (5962-8958701XA)
See NS Package Number WG16A
(TO-263) Surface-Mount Package
DS008822-11
Top View
DS008822-12
Side View
Order Number LM2940CS-5.0, LM2940CS-9.0,
LM2940CS-12, LM2940CS-15,
LM2940S-5.0, LM2940S-8.0,
LM2940S-9.0, LM2940S-10 or LM2940S-12
See NS Package Number TS3B
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2
TO-263 (S) Package
SOT-223 (MP) Package
ESD Susceptibility (Note 3)
If Military/Aerospace specified devices are required,
please contact the National Semiconductor Sales Office/
Distributors for availability and specifications.
260˚C, 4s
260˚C, 4s
2 kV
Operating Conditions (Note 1)
LM2940S, 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
Lead Temperature, Time for Wave Soldering
TO-220 (T) Package
260˚C, 10s
Input Voltage
Temperature Range
LM2940T, LM2940S
LM2940CT, LM2940CS
LM2940IMP
LM2940J, LM2940WG
26V
−40˚C ≤ TJ ≤ 125˚C
0˚C ≤ TJ ≤ 125˚C
−40˚C ≤ TJ ≤ 85˚C
−55˚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)
Parameter
Conditions
5V
Typ
8V
LM2940
LM2940/883
Limit
Limit
(Note 4)
(Note 5)
Typ
6.25V ≤ VIN ≤ 26V
Output Voltage
Line Regulation
5 mA ≤ IO ≤ 1A
4.85/4.75
4.85/4.75
5.15/5.25
5.15/5.25
20
50
40/50
LM2940, LM2940/883
35
50/80
50/100
LM2940C
35
50
VO + 2V ≤ VIN ≤ 26V,
5.00
LM2940
LM2940/883
Limit
Limit
(Note 4)
(Note 5)
Units
9.4V ≤ VIN ≤ 26V
8.00
7.76/7.60
7.76/7.60
VMIN
8.24/8.40
8.24/8.40
VMAX
20
80
50/80
mVMAX
55
80/130
80/130
mVMAX
55
80
1000/1000
mΩ
IO = 5 mA
Load Regulation
50 mA ≤ IO ≤ 1A
Output
100 mADC and
Impedance
20 mArms,
Quiescent
VO +2V ≤ VIN ≤ 26V,
Current
IO = 5 mA
35
1000/1000
55
15/20
10
15/20
15/20
mAMAX
50/60
30
45/60
50/60
mAMAX
700/700
240
1000/1000
µVrms
fO = 120 Hz
LM2940, LM2940/883
10
15/20
LM2940C
10
15
VIN = VO + 5V,
30
45/60
IO = 1A
Output Noise
10 Hz − 100 kHz,
Voltage
IO = 5 mA
Ripple Rejection
fO = 120 Hz, 1 Vrms,
150
IO = 100 mA
LM2940
72
60/54
66
54/48
LM2940C
72
60
66
54
fO = 1 kHz, 1 Vrms,
60/50
dBMIN
54/48
dBMIN
IO = 5 mA
Long Term
20
32
mV/
Stability
Dropout Voltage
Short Circuit
Current
1000 Hr
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
1.9
1.6
1.5/1.3
1.9
1.6
1.6/1.3
AMIN
(Note 6)
3
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LM2940/LM2940C
Absolute Maximum Ratings (Note 1)
LM2940/LM2940C
Electrical Characteristics
(Continued)
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)
Parameter
5V
Conditions
Maximum Line
Typ
8V
LM2940
LM2940/883
Limit
Limit
(Note 4)
(Note 5)
Typ
LM2940
LM2940/883
Limit
Limit
(Note 4)
(Note 5)
Units
RO = 100Ω
LM2940, T ≤ 100 ms
Transient
75
60/60
75
LM2940/883, T ≤ 20 ms
LM2940C, T ≤ 1 ms
55
45
LM2940, LM2940/883
−30
−15/−15
LM2940C
−30
−15
−75
−50/−50
Reverse Polarity
RO = 100Ω
DC Input Voltage
Reverse Polarity
60/60
40/40
−15/−15
40/40
55
45
−30
−15/−15
−30
−15
−75
−50/−50
−15/−15
VMIN
VMIN
RO = 100Ω
Transient Input
LM2940, T ≤ 100 ms
Voltage
LM2940/883, T ≤ 20 ms
LM2940C, T ≤ 1 ms
−45/−45
−55
VMIN
−45/−45
−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
LM2940
Parameter
Conditions
Typ
Limit
LM2940
Typ
(Note 4)
10.5V ≤ VIN ≤ 26V
Output Voltage
5 mA ≤ IO ≤1A
9.00
8.73/8.55
VO + 2V ≤ VIN ≤ 26V,
Units
(Note 4)
11.5V ≤ VIN ≤ 26V
10.00
9.27/9.45
Line Regulation
Limit
9.70/9.50
VMIN
10.30/10.50
VMAX
20
90
20
100
mVMAX
LM2940
60
90/150
65
100/165
mVMAX
LM2940C
60
90
IO = 5 mA
Load Regulation
Output Impedance
50 mA ≤ IO ≤ 1A
100 mADC and
20 mArms,
60
65
mΩ
fO = 120 Hz
Quiescent
Current
VO +2V ≤ VIN < 26V,
IO = 5 mA
LM2940
10
15/20
LM2940C
10
15
45/60
VIN = VO + 5V, IO = 1A
30
Output Noise
10 Hz − 100 kHz,
270
Voltage
IO = 5 mA
Ripple Rejection
fO = 120 Hz, 1 Vrms,
10
15/20
mAMAX
30
45/60
mAMAX
300
µVrms
IO = 100 mA
LM2940
64
52/46
LM2940C
64
52
Long Term
Stability
Dropout Voltage
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34
63
51/45
36
dBMIN
mV/
1000 Hr
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
4
(Continued)
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
LM2940
Parameter
Conditions
Typ
Limit
LM2940
Typ
(Note 4)
Short Circuit
(Note 6)
Units
Limit
(Note 4)
1.9
1.6
1.9
1.6
AMIN
LM2940
75
60/60
75
60/60
VMIN
LM2940C
55
45
−30
−15/−15
VMIN
−75
−50/−50
VMIN
Current
Maximum Line
RO = 100Ω
Transient
T ≤ 100 ms
Reverse Polarity
RO = 100Ω
DC Input Voltage
LM2940
−30
−15/−15
LM2940C
−30
−15
Reverse Polarity
RO = 100Ω
Transient Input
T ≤ 100 ms
Voltage
LM2940
−75
−50/−50
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
LM2940
Parameter
Conditions
Typ
15V
LM2940/833
Limit
Limit
(Note 4)
(Note 5)
LM2940
Typ
13.6V ≤ VIN ≤ 26V
Output Voltage
5 mA ≤ IO ≤1A
Line Regulation
VO + 2V ≤ VIN ≤ 26V,
12.00
11.64/11.40
11.64/11.40
12.36/12.60
12.36/12.60
20
120
75/120
LM2940, LM2940/883
55
120/200
120/190
LM2940C
55
120
LM2940/833
Limit
Limit
(Note 4)
(Note 5)
Units
16.75V ≤ VIN ≤ 26V
15.00
14.55/14.25
14.55/14.25
VMIN
15.45/15.75
15.45/15.75
VMAX
20
150
95/150
mVMAX
150/240
mVMAX
70
150
1000/1000
mΩ
15/20
mAMAX
50/60
mAMAX
1000/1000
µVrms
IO = 5 mA
Load Regulation
Output
Impedance
50 mA ≤ IO ≤ 1A
100 mADC and
20 mArms,
80
1000/1000
100
fO = 120 Hz
Quiescent
Current
VO +2V ≤ VIN ≤ 26V,
IO = 5 mA
LM2940, LM2940/883
10
15/20
LM2940C
10
15
VIN = VO + 5V, IO = 1A
30
45/60
Output Noise
10 Hz − 100 kHz,
360
Voltage
IO = 5 mA
Ripple Rejection
fO = 120 Hz, 1 Vrms,
15/20
10
15
50/60
30
45/60
1000/1000
450
IO = 100 mA
LM2940
66
54/48
LM2940C
66
54
dBMIN
64
fO = 1 kHz, 1 Vrms,
52/46
IO = 5 mA
5
52
48/42
dBMIN
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LM2940/LM2940C
Electrical Characteristics
LM2940/LM2940C
Electrical Characteristics
(Continued)
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
LM2940
Parameter
Conditions
Long Term
Short Circuit
Limit
Limit
(Note 4)
(Note 5)
48
Stability
Dropout Voltage
Typ
15V
LM2940/833
LM2940
Typ
LM2940/833
Limit
Limit
(Note 4)
(Note 5)
Units
mV/
60
1000 Hr
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
1.9
1.6
1.6/1.3
1.9
1.6
1.6/1.3
AMIN
75
60/60
40/40
VMIN
55
45
55
45
−15/−15
VMIN
−30
−15
−45/−45
VMIN
(Note 6)
Current
Maximum Line
RO = 100Ω
Transient
LM2940, T ≤ 100 ms
LM2940/883, T ≤ 20 ms
LM2940C, T ≤ 1 ms
40/40
Reverse Polarity
RO = 100Ω
DC Input
LM2940, LM2940/883
−30
−15/−15
Voltage
LM2940C
−30
−15
Reverse Polarity
RO = 100Ω
−75
−50/−50
Transient Input
LM2940, T ≤ 100 ms
Voltage
LM2940/883, T ≤ 20 ms
LM2940C, T ≤ 1 ms
−15/−15
−45/−45
−55
−45/−45
−55
−45/−45
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, θJ−A, 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 θJ−A (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 θJ−A can be reduced by using a heatsink (see Application Hints for specific information on heatsinking). The values of θJ−A and θJ−Cfor the K02A
package are 39˚C/W and 4˚C/W respectively.
Note 3: ESD rating is based on the human body model, 100 pF discharged through 1.5 kΩ.
Note 4: 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 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 are 100% production tested and are used to calculate Outgoing Quality Levels.
Note 6: Output current will decrease with increasing temperature but will not drop below 1A at the maximum specified temperature.
Typical Performance Characteristics
Dropout Voltage
Dropout Voltage
vs Temperature
Output Voltage
vs Temperature
DS008822-13
DS008822-14
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6
DS008822-15
Quiescent Current
vs Temperature
LM2940/LM2940C
Typical Performance Characteristics
(Continued)
Quiescent Current
Quiescent Current
DS008822-18
DS008822-17
DS008822-16
Line Transient Response
Load Transient Response
Low Voltage Behavior
DS008822-25
Low Voltage Behavior
DS008822-21
DS008822-20
DS008822-19
Low Voltage Behavior
Ripple Rejection
Low Voltage Behavior
DS008822-27
DS008822-26
Low Voltage Behavior
DS008822-28
Low Voltage Behavior
DS008822-29
7
DS008822-30
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LM2940/LM2940C
Typical Performance Characteristics
Output at
Voltage Extremes
(Continued)
Output at
Voltage Extremes
DS008822-31
Output at
Voltage Extremes
DS008822-32
Output at
Voltage Extremes
DS008822-34
DS008822-33
Output at
Voltage Extremes
DS008822-35
Output Capacitor ESR
DS008822-36
Peak Output Current
DS008822-8
DS008822-6
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Output at
Voltage Extremes
8
Output Impedance
LM2940/LM2940C
Typical Performance Characteristics
(Continued)
Maximum Power
Dissipation (TO-220)
Maximum Power
Dissipation (TO-3)
DS008822-22
DS008822-23
DS008822-24
Maximum Power Dissipation
(TO-263) See (Note 2)
DS008822-10
9
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LM2940/LM2940C
Equivalent Schematic Diagram
DS008822-1
Application Hints
EXTERNAL CAPACITORS
The output capacitor is critical to maintaining regulator stability, and must meet the required conditions for both ESR
(Equivalent Series Resistance) and minimum amount of capacitance.
MINIMUM CAPACITANCE:
The minimum output capacitance required to maintain stability is 22 µF (this value may be increased without limit).
Larger values of output capacitance will give improved transient response.
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 essential that the output capacitor meet these requirements,
or oscillations can result.
Output Capacitor ESR
DS008822-6
FIGURE 1. ESR Limits
It is important to note that for most capacitors, ESR is specified 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 temperature, but are more expensive than aluminum electrolytics. A cost-effective approach sometimes used is to parallel
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10
If a manufactured heatsink is to be selected, the value of
heatsink-to-ambient thermal resistance, θ(H−A), must first be
calculated:
(Continued)
an aluminum electrolytic with a solid Tantalum, with the total
capacitance split about 75/25% with the Aluminum being the
larger value.
θ(H−A) = θ(J−A) − θ(C−H) − θ(J−C)
Where: θ(J−C)
If two capacitors are paralleled, the effective ESR is the parallel of the two individual values. The “flatter” ESR of the Tantalum will keep the effective ESR from rising as quickly at low
temperatures.
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 calculation.
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 attachment, 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.
HEATSINKING
A heatsink may be required depending on the maximum
power dissipation and maximum ambient temperature of the
application. Under all possible operating conditions, the junction temperature must be within the range specified under
Absolute 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:
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 AND SOT-223 PACKAGE PARTS
Both the TO-263 (“S”) and 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 3 shows for the TO-263 the measured values of θ(J−A)
for different copper area sizes using a typical PCB with 1
ounce copper and no solder mask over the copper area used
for heatsinking.
DS008822-37
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 using the formula:
TR (max) = TJ(max) − TA (max)
where: TJ (max) is the maximum allowable junction temperature, 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 resistance, θ(J−A), can now be found:
θ(J−A) = TR (max)/PD
DS008822-38
FIGURE 3. θ(J−A) 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(J−A) for the TO-263
package mounted to a PCB is 32˚C/W.
As a design aid, Figure 4 shows the maximum allowable
power dissipation compared to ambient temperature for the
TO-263 device (assuming θ(J−A) is 35˚C/W and the maximum junction temperature is 125˚C).
IMPORTANT: If the maximum allowable value for θ(J−A) 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 package, no heatsink is needed since the package alone will dissipate enough heat to satisfy these requirements.
If the calculated value for θ(J−A)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(J−A) will be the same as shown in
the next section for the TO-263.
11
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LM2940/LM2940C
Application Hints
LM2940/LM2940C
Application Hints
(Continued)
DS008822-40
FIGURE 5. θ(J−A) vs Copper (2 ounce) Area for the
SOT-223 Package
DS008822-39
FIGURE 4. Maximum Power Dissipation vs TAMB for
the TO-263 Package
Figure 5 and Figure 6 show the information for the SOT-223
package. Figure 6 assumes a θ(J−A) of 74˚C/W for 1 ounce
copper and 51˚C/W for 2 ounce copper and a maximum
junction temperature of 125˚C.
DS008822-41
FIGURE 6. Maximum Power Dissipation vs TAMB for
the SOT-223 Package
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12
LM2940/LM2940C
Physical Dimensions
inches (millimeters) unless otherwise noted
3-Lead SOT-223 Package
Order Part Number LM2940IMP-5.0
LM2940IMP-8.0 LM2940IMP-9.0
LM2940IMP-10 LM2940IMP-12 LM2940IMP-15
NS Package Number MP04A
13
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LM2940/LM2940C
Physical Dimensions
inches (millimeters) unless otherwise noted (Continued)
16 Lead Dual-in-Line Package (J)
Order Number LM2940J-5.0/883 (5962-8958701EA),
LM2940J-8.0/883 (5962-9088301QEA),
LM2940J-12/883 (5962-9088401QEA),
LM2940J-15/883 (5962-9088501QEA)
See NS Package Number J16A
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14
LM2940/LM2940C
Physical Dimensions
inches (millimeters) unless otherwise noted (Continued)
16 Lead Surface Mount Package (WG)
Order Number LM2940WG5.0/883 (5962-8958701XA)
See NS Package Number WG16A
15
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LM2940/LM2940C
Physical Dimensions
inches (millimeters) unless otherwise noted (Continued)
3-Lead TO-220 Plastic Package (T)
Order Number LM2940T-5.0, LM2940T-8.0,
LM2940T-9.0, LM2940T-10, LM2940T-12, LM2940CT-5.0,
LM2940CT-12 or LM2940CT-15
NS Package Number TO3B
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16
LM2940/LM2940C 1A Low Dropout Regulator
Physical Dimensions
inches (millimeters) unless otherwise noted (Continued)
3-Lead TO-263 Surface Mount Package (MP)
Order Number LM2940S-5.0, LM2940S-8.0,
LM2940S-9.0, LM2940S-10, LM2940S-12,
LM2940CS-5.0, LM2940CS-12 or LM2940CS-15
NS Package Number TS3B
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