LT1129/LT1129-3.3/LT1129-5
Micropower Low Dropout
Regulators with Shutdown
FEATURES
DESCRIPTION
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The LT ®1129/LT1129-3.3/LT1129-5 are micropower low
dropout regulators with shutdown. The devices are capable
of supplying 700mA of output current with a dropout
voltage of 400mV at maximum output. Designed for use
in battery-powered systems, the low quiescent current,
50μA operating and 16μA in shutdown, make them an ideal
choice. The quiescent current does not rise in dropout as
it does with many other low dropout PNP regulators.
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400mV Dropout Voltage
700mA Output Current
50μA Quiescent Current
No Protection Diodes Needed
Adjustable Output from 3.8V to 30V
3.3V and 5V Fixed Output Voltages
Controlled Quiescent Current in Dropout
Shutdown
16μA Quiescent Current in Shutdown
Stable with 3.3μF Output Capacitor
Reverse Battery Protection
No Reverse Output Current
Thermal Limiting
Surface Mount SOT-223 and DD-Pak Packages
APPLICATIONS
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Low Current Regulator
Regulator for Battery-Powered Systems
Post Regulator for Switching Supplies
5V to 3.3V Logic Regulator
Other features of the LT1129 /LT1129-3.3/LT1129-5 include
the ability to operate with small output capacitors. They
are stable with only 3.3μF on the output while most older
devices require between 10μF and 100μF for stability. Also
the input may be connected to ground or a reverse voltage
without reverse current flow from output to input. This
makes the LT1129/LT1129-3.3/LT1129-5 ideal for backup
power situations where the output is held high and the
input is at ground or reversed. Under these conditions,
only 16μA will flow from the output pin to ground. The
devices are available in 5-lead TO-220, 5-lead DD-Pak and
3-lead SOT-223 packages.
L, LT, LTC and LTM are registered trademarks of Linear Technology Corporation.
All other trademarks are the property of their respective owners.
TYPICAL APPLICATION
5V Supply with Shutdown
Dropout Voltage
0.6
IN
OUT
1
+
LT1129-5
VIN > 5.5V
4
SENSE
5V OUT
500mA
2
3.3μF
SOLID TANTALUM
SHDN
GND
3
VSHDN (PIN 4) OUTPUT
OFF
< 0.25
ON
> 2.8
ON
NC
0.5
DROPOUT VOLTAGE (V)
5
0.4
0.3
0.2
0.1
112935 TA01
0
0
0.1
0.5
0.2 0.3 0.4
OUTPUT CURRENT (A)
0.6
0.7
112935 TA02
112935ff
1
LT1129/LT1129-3.3/LT1129-5
ABSOLUTE MAXIMUM RATINGS
(Note 1)
Input Voltage ...................................................... ± 30V*
Output Pin Reverse Current ................................. 10mA
Sense Pin Current ................................................ 10mA
Adjust Pin Current ................................................ 10mA
Sense Pin, Adjust Pin Reverse Voltage ............... – 0.6V
Shutdown Pin Input Voltage (Note 2) ......... 6.5V, – 0.6V
Shutdown Pin Input Current (Note 2) .................. 20mA
Output Short-Circuit Duration .......................... Indefinite
Storage Temperature Range.................. – 65°C to 150°C
Operating Junction Temperature Range (Note 3)
LT1129C-X .......................................... 0°C to 125°C
LT1129C-X Extended Temperature Range
(Note 12) ....................................... –40°C to 125°C
LT1129I-X(Note 12) ......................... –40°C to 125°C
LT1129MP-X(Note 12) ..................... –55°C to 125°C
Lead Temperature (Soldering, 10 sec) .................. 300°C
* For applications requiring input voltage ratings greater than 30V, contact the factory.
PIN CONFIGURATION
TOP VIEW
GND
1
20 GND
GND
2
19 GND
GND
3
18 GND
GND
4
17 GND
GND
5
16 GND
GND
6
15 GND
OUT
7
14 IN
SENSE
8
13 SHDN
9
12 GND
GND 10
11 GND
GND
FRONT VIEW
TAB
IS
GND
VIN
4
SHDN
3
GND
2
SENSE/ADJ*
OUTPUT 1
SENSE/ 2
ADJ*
GND 3
8 VIN
7 GND
6 GND
5 SHDN
NC 4
OUTPUT
1
F PACKAGE
20-LEAD PLASTIC TSSOP
TOP VIEW
5
Q PACKAGE
5-LEAD PLASTIC DD
S8 PACKAGE
8-LEAD PLASTIC SO
*PIN 2 = SENSE FOR LT1129-3.3/LT1129-5
= ADJ FOR LT1129
θJA = 30°C/W
*PIN 2 = SENSE FOR LT1129-3.3/LT1129-5
= ADJ FOR LT1129
θJA = 60°C/W
NOTE: ALL GROUND PINS ARE INTERNALLY CONNECTED
θJA = 40°C/W
OBSOLETE PACKAGE
FRONT VIEW
FRONT VIEW
3
TAB
IS
GND
2
1
OUTPUT
TAB
IS
GND
GND
VIN
5
VIN
4
SHDN
3
GND
2
SENSE/ADJ*
1
OUTPUT
T PACKAGE
5-LEAD PLASTIC TO-220
ST PACKAGE
3-LEAD PLASTIC SOT-223
*PIN 2 = SENSE FOR LT1129-3.3/LT1129-5 = ADJ FOR LT1129
θJA = 50°C/W
θJA = 50°C/W
ORDER INFORMATION
LEAD FREE FINISH
TAPE AND REEL
PART MARKING*
PACKAGE DESCRIPTION
TEMPERATURE RANGE
LT1129CS8#PBF
LT1129CS8#TRPBF
1129
8-Lead Plastic SO
0°C to 125°C
LT1129IS8#PBF
LT1129IS8#TRPBF
1129I
8-Lead Plastic SO
–40°C to 125°C
LT1129CS8-3.3#PBF
LT1129CS8-3.3#TRPBF
11293
8-Lead Plastic SO
0°C to 125°C
LT1129IS8-3.3#PBF
LT1129IS8-3.3#TRPBF
1129I3
8-Lead Plastic SO
–40°C to 125°C
LT1129CS8-5#PBF
LT1129CS8-5#TRPBF
11295
8-Lead Plastic SO
0°C to 125°C
112935ff
2
LT1129/LT1129-3.3/LT1129-5
ORDER INFORMATION
LEAD FREE FINISH
TAPE AND REEL
PART MARKING*
PACKAGE DESCRIPTION
TEMPERATURE RANGE
LT1129IS8-5#PBF
LT1129IS8-5#TRPBF
1129I5
8-Lead Plastic SO
–40°C to 125°C
LT1129CST-3.3#PBF
LT1129CST-3.3#TRPBF
11293
3-Lead Plastic SOT-223
0°C to 125°C
LT1129IST-3.3#PBF
LT1129IST-3.3#TRPBF
129I3
3-Lead Plastic SOT-223
–40°C to 125°C
LT1129MPST-3.3#PBF
LT1129MPST-3.3#TRPBF
129MP3
3-Lead Plastic SOT-223
–55°C to 125°C
LT1129CST-5#PBF
LT1129CST-5#TRPBF
11295
3-Lead Plastic SOT-223
0°C to 125°C
LT1129IST-5#PBF
LT1129IST-5#TRPBF
129I5
3-Lead Plastic SOT-223
–40°C to 125°C
LT1129CQ#PBF
LT1129CQ#TRPBF
LT1129CQ
5-Lead Plastic DD-PAK
0°C to 125°C
LT1129IQ#PBF
LT1129IQ#TRPBF
LT1129IQ
5-Lead Plastic DD-PAK
–40°C to 125°C
LT1129CQ-3.3#PBF
LT1129CQ-3.3#TRPBF
LT1129CQ-3.3
5-Lead Plastic DD-PAK
0°C to 125°C
LT1129IQ-3.3#PBF
LT1129IQ-3.3#TRPBF
LT1129IQ-3.3
5-Lead Plastic DD-PAK
–40°C to 125°C
LT1129CQ-5#PBF
LT1129CQ-5#TRPBF
LT1129CQ-5
5-Lead Plastic DD-PAK
0°C to 125°C
LT1129IQ-5#PBF
LT1129IQ-5#TRPBF
LT1129IQ-5
5-Lead Plastic DD-PAK
–40°C to 125°C
LT1129CT#PBF
LT1129CT#TRPBF
LT1129CT
5-Lead Plastic TO-220
0°C to 125°C
LT1129IT#PBF
LT1129IT#TRPBF
LT1129IT
5-Lead Plastic TO-220
–40°C to 125°C
LT1129CT-3.3#PBF
LT1129CT-3.3#TRPBF
LT1129CT-3.3
5-Lead Plastic TO-220
0°C to 125°C
LT1129IT-3.3#PBF
LT1129IT-3.3#TRPBF
LT1129IT-3.3
5-Lead Plastic TO-220
–40°C to 125°C
LT1129CT-5#PBF
LT1129CT-5#TRPBF
LT1129CT-5
5-Lead Plastic TO-220
0°C to 125°C
LT1129IT-5#PBF
LT1129IT-5#TRPBF
LT1129IT-5
5-Lead Plastic TO-220
–40°C to 125°C
LEAD BASED FINISH
TAPE AND REEL
PART MARKING*
PACKAGE DESCRIPTION
TEMPERATURE RANGE
LT1129CS8
LT1129CS8#TR
1129
8-Lead Plastic SO
0°C to 125°C
LT1129IS8
LT1129IS8#TR
1129I
8-Lead Plastic SO
–40°C to 125°C
LT1129CS8-3.3
LT1129CS8-3.3#TR
11293
8-Lead Plastic SO
0°C to 125°C
LT1129IS8-3.3
LT1129IS8-3.3#TR
1129I3
8-Lead Plastic SO
–40°C to 125°C
LT1129CS8-5
LT1129CS8-5#TR
11295
8-Lead Plastic SO
0°C to 125°C
LT1129IS8-5
LT1129IS8-5#TR
1129I5
8-Lead Plastic SO
–40°C to 125°C
LT1129CST-3.3
LT1129CST-3.3#TR
11293
3-Lead Plastic SOT-223
0°C to 125°C
LT1129IST-3.3
LT1129IST-3.3#TR
129I3
3-Lead Plastic SOT-223
–40°C to 125°C
LT1129MPST-3.3
LT1129MPST-3.3#TR
129MP3
3-Lead Plastic SOT-223
–55°C to 125°C
LT1129CST-5
LT1129CST-5#TR
11295
3-Lead Plastic SOT-223
0°C to 125°C
LT1129IST-5
LT1129IST-5#TR
129I5
3-Lead Plastic SOT-223
–40°C to 125°C
LT1129CQ
LT1129CQ#TR
LT1129CQ
5-Lead Plastic DD-PAK
0°C to 125°C
LT1129IQ
LT1129IQ#TR
LT1129IQ
5-Lead Plastic DD-PAK
–40°C to 125°C
LT1129CQ-3.3
LT1129CQ-3.3#TR
LT1129CQ-3.3
5-Lead Plastic DD-PAK
0°C to 125°C
LT1129IQ-3.3
LT1129IQ-3.3#TR
LT1129IQ-3.3
5-Lead Plastic DD-PAK
–40°C to 125°C
LT1129CQ-5
LT1129CQ-5#TR
LT1129CQ-5
5-Lead Plastic DD-PAK
0°C to 125°C
LT1129IQ-5
LT1129IQ-5#TR
LT1129IQ-5
5-Lead Plastic DD-PAK
–40°C to 125°C
LT1129CT
LT1129CT#TR
LT1129CT
5-Lead Plastic TO-220
0°C to 125°C
LT1129IT
LT1129IT#TR
LT1129IT
5-Lead Plastic TO-220
–40°C to 125°C
LT1129CT-3.3
LT1129CT-3.3#TR
LT1129CT-3.3
5-Lead Plastic TO-220
0°C to 125°C
LT1129IT-3.3
LT1129IT-3.3#TR
LT1129IT-3.3
5-Lead Plastic TO-220
–40°C to 125°C
112935ff
3
LT1129/LT1129-3.3/LT1129-5
ORDER INFORMATION
LEAD BASED FINISH
TAPE AND REEL
PART MARKING*
PACKAGE DESCRIPTION
TEMPERATURE RANGE
LT1129CT-5
LT1129CT-5#TR
LT1129CT-5
5-Lead Plastic TO-220
0°C to 125°C
LT1129IT-5
LT1129IT-5#TR
LT1129IT-5
5-Lead Plastic TO-220
–40°C to 125°C
Consult LTC Marketing for parts specified with wider operating temperature ranges. *The temperature grade is identified by a label on the shipping container.
For more information on lead free part marking, go to: http://www.linear.com/leadfree/
For more information on tape and reel specifications, go to: http://www.linear.com/tapeandreel/
ELECTRICAL CHARACTERISTICS
The l denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at TA = 25°C.
SYMBOL
CONDITIONS
Regulated Output Voltage
(Notes 4, 12)
LT1129-3.3
VIN = 3.8V, IOUT = 1mA, TJ = 25°C
4.3V < VIN < 20V, 1mA < IOUT < 700mA
LT1129-5
Line Regulation (Note 12)
Load Regulation (Note 12)
Dropout Voltage
(Note 6)
Ground Pin Current
(Note 7)
MIN
TYP
MAX
UNITS
l
3.250
3.200
3.300
3.300
3.350
3.400
V
V
VIN = 5.5V, IOUT = 1mA, TJ = 25°C
6V < VIN < 20V, 1mA < IOUT < 700mA
l
4.925
4.850
5.000
5.000
5.075
5.150
V
V
LT1129 (Note 5)
VIN = 4.3V, IOUT = 1mA, TJ = 25°C
4.8V < VIN < 20V, 1mA < IOUT < 700mA
l
3.695
3.640
3.750
3.750
3.805
3.860
V
V
LT1129-3.3
ΔVIN = 4.8V to 20V, IOUT = 1mA
l
1.5
10
mV
LT1129-5
ΔVIN = 5.5V to 20V, IOUT = 1mA
l
1.5
10
mV
LT1129 (Note 5)
ΔVIN = 4.3V to 20V, IOUT = 1mA
l
1.5
10
mV
LT1129-3.3
ΔILOAD = 1mA to 700mA, TJ = 25°C
ΔILOAD = 1mA to 700mA
l
6
15
20
30
mV
mV
LT1129-5
ΔILOAD = 1mA to 700mA, TJ = 25°C
ΔILOAD = 1mA to 700mA
l
6
20
20
30
mV
mV
LT1129 (Note 5)
ΔILOAD = 1mA to 700mA, TJ = 25°C
ΔILOAD = 1mA to 700mA
l
6
15
20
30
mV
mV
0.13
0.20
0.25
V
V
0.25
0.35
0.45
V
V
0.37
0.45
0.60
V
V
0.45
0.55
0.70
V
V
ILOAD = 10mA, TJ = 25°C
ILOAD = 10mA
l
ILOAD = 100mA, TJ = 25°C
ILOAD = 100mA
l
ILOAD = 500mA, TJ = 25°C
ILOAD = 500mA
l
ILOAD = 700mA, TJ = 25°C
ILOAD = 700mA
l
ILOAD = 0mA
l
50
70
μA
ILOAD = 10mA
l
310
450
μA
ILOAD = 100mA
l
2.0
3.5
mA
ILOAD = 300mA
l
10
20
mA
ILOAD = 500mA
l
25
45
mA
ILOAD = 700mA
l
50
90
mA
150
300
nA
1.2
0.75
2.8
V
V
Adjust Pin Bias Current (Notes 5, 8)
TJ = 25°C
Shutdown Threshold
VOUT = Off to On
VOUT = On to Off
l
l
Shutdown Pin Current (Note 9)
VSHDN = 0V
l
6
10
μA
Quiescent Current in Shutdown
(Note 10)
VIN = 6V, VSHDN = 0V
l
15
25
μA
0.25
112935ff
4
LT1129/LT1129-3.3/LT1129-5
ELECTRICAL CHARACTERISTICS
The l denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at TA = 25°C.
SYMBOL
CONDITIONS
Ripple Rejection
VIN – VOUT = 1V (Avg), VRIPPLE = 0.5VP-P,
fRIPPLE = 120Hz, ILOAD = 0.7A, TJ = 25°C
Current Limit
VIN – VOUT = 7V, TJ = 25°C
Input Reverse Leakage Current
VIN = –20V, VOUT = 0V
Reverse Output Current (Note 11)
LT1129-3.3
LT1129-5
LT1129 (Note 5)
MIN
TYP
52
64
MAX
1.2
l
VOUT = 3.3V, VIN = 0V
VOUT = 5V, VIN = 0V
VOUT = 3.8V, VIN = 0V
Note 1: Stresses beyond those listed under Absolute Maximum Ratings
may cause permanent damage to the device. Exposure to any Absolute
Maximum Rating condition for extended periods may affect device
reliability and lifetime.
Note 2: The shutdown pin input voltage rating is required for a low
impedance source. Internal protection devices connected to the shutdown
pin will turn on and clamp the pin to approximately 7V or – 0.6V. This
range allows the use of 5V logic devices to drive the pin directly. For high
impedance sources or logic running on supply voltages greater than 5.5V,
the maximum current driven into the shutdown pin must be limited to less
than 20mA.
Note 3: For junction temperatures greater than 110°C, a minimum load
of 1mA is recommended. For TJ > 110°C and IOUT < 1mA, output voltage
may increase by 1%.
Note 4: Operating conditions are limited by maximum junction
temperature. The regulated output voltage specification will not apply
for all possible combinations of input voltage and output current. When
operating at maximum input voltage, the output current range must be
limited. When operating at maximum output current, the input voltage
range must be limited.
Note 5: The LT1129 is tested and specified with the adjust pin connected
to the output pin.
Note 6: Dropout voltage is the minimum input/output voltage required to
maintain regulation at the specified output current. In dropout the output
16
16
16
UNITS
dB
1.6
A
1.0
mA
25
25
25
μA
μA
μA
voltage will be equal to (VIN – VDROPOUT). Dropout voltage is measured
between the input pin and the output pin. External voltage drops between
the output pin and the sense pin will add to the dropout voltage.
Note 7: Ground pin current is tested with VIN = VOUT (nominal) and a
current source load. This means that the device is tested while operating in
its dropout region. This is the worst case ground pin current. The ground
pin current will decrease slightly at higher input voltages.
Note 8: Adjust pin bias current flows into the adjust pin.
Note 9: Shutdown pin current at VSHDN = 0V flows out of the shutdown pin.
Note 10: Quiescent current in shutdown is equal to the sum total of the
shutdown pin current (6μA) and the ground pin current (9μA).
Note 11: Reverse output current is tested with the input pin grounded. The
output pin and the sense pin are forced to the rated output voltage. This
current flows into the sense pin and out of the ground pin. For the LT1129
(adjustable version) the sense pin is internally tied to the output pin.
Note 12: The LT1129 regulators are tested and specified under pulse load
conditions such that TJ ≅ TA. The LT1129C regulators are 100% tested at
TA = 25°C. For C-grade devices, Regulated Output Voltage, Line Regulation
and Load Regulation performance at –40°C and 125°C is assured by
design, characterization and correlation with statistical process controls.
The LT1129I regulators are guaranteed over the full –40°C to 125°C
operating junction temperature range. The LT1129MP regulators are 100%
tested and guaranteed over the –55°C to 125°C temperature range.
TYPICAL PERFORMANCE CHARACTERISTICS
Dropout Voltage
0.6
0.6
TJ ≤ 125°C
0.5
TJ ≤ 25°C
0.4
0.3
0.2
0.1
0.5
Quiescent Current
70
A. ILOAD = 700mA
B. ILOAD = 500mA
C. ILOAD = 300mA
D. ILOAD = 100mA
E. ILOAD = 10mA
60
A
QUIESCENT CURRENT (μA)
0.7
DROPOUT VOLTAGE (V)
DROPOUT VOLTAGE (V)
Guaranteed Dropout Voltage
0.7
B
C
0.4
D
0.3
E
0.2
0.1
VSHDN = OPEN (HI)
50
40
30
VSHDN = 0V
20
10
= TEST POINTS
0
0
0.1
0.3 0.4
0.2
0.5
OUTPUT CURRENT (A)
0.6
0.7
112935 G01
0
–50
–25
50
25
0
75
TEMPERATURE (°C)
100
125
112935 G02
0
–50
–25
50
25
0
75
TEMPERATURE (°C)
100
125
112935 G03
112935ff
5
LT1129/LT1129-3.3/LT1129-5
TYPICAL PERFORMANCE CHARACTERISTICS
LT1129-3.3
Quiescent Current
LT1129-5
Quiescent Current
250
ILOAD = 0
RLOAD = ∞
225
QUIESCENT CURRENT (μA)
200
175
150
VSHDN = OPEN (HI)
125
100
75
50
VSHDN = 0V
25
250
ILOAD = 0
RLOAD = ∞
225
200
175
150
VSHDN = OPEN (HI)
125
100
75
50
VSHDN = 0V
25
0
1
2
3 4 5 6 7
INPUT VOLTAGE (V)
8
9
0
10
1
2
3 4 5 6 7
INPUT VOLTAGE (V)
8
LT1129-3.3
Output Voltage
10
3.300
3.275
3.250
3.225
50
25
0
75
TEMPERATURE (°C)
100
125
5.025
5.000
4.975
4.950
0.8
0.6
RLOAD = 330Ω
ILOAD = 10mA*
0.4
50
25
0
75
TEMPERATURE (°C)
–25
*FOR VOUT = 3.3V
0
0
1
2
3 4 5 6 7
INPUT VOLTAGE (V)
1.6
100
125
9
10
112935 G10
ILOAD = 1mA
3.750
3.725
3.700
3.650
–50
50
25
0
75
TEMPERATURE (°C)
–25
100
125
112935 G09
LT1129
Ground Pin Current
1.2
RLOAD = 100Ω
ILOAD = 50mA*
1.0
0.8
0.6
RLOAD = 500Ω
ILOAD = 10mA*
0.4
1
2
3 4 5 6 7
INPUT VOLTAGE (V)
1.6
1.4
8
9
10
112935 G11
RLOAD = 38Ω
ILOAD = 100mA*
1.2
RLOAD = 75Ω
ILOAD = 50mA*
1.0
0.8
0.6
RLOAD = 375Ω
ILOAD = 10mA*
0.4
0.2
*FOR VOUT = 5V
0
TJ = 25°C
VOUT =
VADJ
1.8
RLOAD = 50Ω
ILOAD = 100mA*
1.4
0
8
10
2.0
TJ = 25°C
VOUT = VSENSE
0.2
0.2
9
3.775
GROUND PIN CURRENT (mA)
GROUND PIN CURRENT (mA)
RLOAD = 66Ω
ILOAD = 50mA*
8
112935 G08
1.8
1.0
3 4 5 6 7
INPUT VOLTAGE (V)
3.800
2.0
1.2
2
3.675
4.900
–50
2.0
1.4
1
112935 G06
LT1129-5
Ground Pin Current
RLOAD = 33Ω
ILOAD = 100mA*
VSHDN = 0V
3.825
5.050
LT1129-3.3
Ground Pin Current
1.6
50
3.850
112935 G07
1.8
75
LT1129
Adjust Pin Voltage
4.925
TJ = 25°C
VOUT =
VSENSE
100
0
ADJUST PIN VOLTAGE (V)
OUTPUT VOLTAGE (V)
ADJUST PIN VOLTAGE (V)
3.325
GROUND PIN CURRENT (mA)
9
ILOAD = 1mA
5.075
3.350
VSHDN = OPEN (HI)
125
0
5.100
ILOAD = 1mA
–25
150
LT1129-5
Output Voltage
3.400
3.200
–50
175
112935 G05
112935 G04
3.375
200
25
0
0
ILOAD = 0
RLOAD = ∞
VOUT = VADJ
225
QUIESCENT CURRENT (μA)
250
QUIESCENT CURRENT (μA)
LT1129
Quiescent Current
*FOR VOUT = 3.75V
0
0
1
2
3 4 5 6 7
INPUT VOLTAGE (V)
8
9
10
112935 G12
112935ff
6
LT1129/LT1129-3.3/LT1129-5
TYPICAL PERFORMANCE CHARACTERISTICS
LT1129-3.3
Ground Pin Current
LT1129-5
Ground Pin Current
60
50
40
RLOAD = 4.7Ω
ILOAD = 700mA*
30
RLOAD = 6.6Ω
ILOAD = 500mA*
20
RLOAD = 11Ω
ILOAD = 300mA*
10
1
2
3 4 5 6 7
INPUT VOLTAGE (V)
50
40
RLOAD = 7.1Ω
ILOAD = 700mA*
30
RLOAD = 10Ω
ILOAD = 500mA*
20
0
8
9
RLOAD = 16.6Ω
ILOAD = 300mA*
10
*FOR VOUT = 3.3V
0
60
TJ = 25°C
VOUT = VSENSE
10
0
1
2
3 4 5 6 7
INPUT VOLTAGE (V)
8
9
TJ = 25°C
30
20
TJ = –50°C
10
0
0.2 0.3 0.4
0.5
OUTPUT CURRENT (A)
0.6
1.4
1.2
1.0
0.8
0.6
0.4
Shutdown Pin Current
–25
50
25
0
75
TEMPERATURE (°C)
4
3
2
1
50
25
0
75
TEMPERATURE (°C)
100
125
112935 G19
9
10
ILOAD = 700mA
1.2
ILOAD = 1mA
1.0
0.8
0.6
0.4
–25
50
25
0
75
TEMPERATURE (°C)
100
125
112935 G18
Adjust Pin Bias Current
400
20
15
10
5
350
VADJ = VOUT = 3.75V
300
250
200
150
100
50
0
–25
8
1.4
0
–50
125
ADJUST PIN BIAS CURRENT (nA)
SHUTDOWN PIN INPUT CURRENT (mA)
SHUTDOWN PIN CURRENT (μA)
5
3 4 5 6 7
INPUT VOLTAGE (V)
1.6
Shutdown Pin Input Current
6
0
–50
100
25
7
2
112935 G17
10
8
1
0.2
0
–50
0.7
VSHDN = 0V
*FOR VOUT = 3.75V
0
1.8
1.6
112935 G16
9
RLOAD = 12.6Ω
ILOAD = 300mA*
2.0
0.2
0.1
20
Shutdown Pin Threshold
(Off-to-On)
SHUTDOWN THRESHOLD (V)
SHUTDOWN THRESHOLD (V)
TJ = 125°C
RLOAD = 7.5Ω
ILOAD = 500mA*
112935 G15
ILOAD = 1mA
1.8
40
0
30
0
10
2.0
50
RLOAD = 5.3Ω
ILOAD = 700mA*
40
Shutdown Pin Threshold
(On-to-Off)
70
60
50
112935 G14
Ground Pin Current
VIN = 3.3V (LT1129-3.3)
VIN = 5V (LT1129-5)
VIN = 3.75V (LT1129)
DEVICE IS OPERATING
IN DROPOUT
TJ = 25°C
VOUT = VADJ
10
*FOR VOUT = 5V
112935 G13
GROUND PIN CURRENT (mA)
GROUND PIN CURRENT (mA)
TJ = 25°C
VOUT = VSENSE
GROUND PIN CURRENT (mA)
GROUND PIN CURRENT (mA)
60
0
LT1129
Ground Pin Current
0
1
7
3
8
2
5
6
4
SHUTDOWN PIN VOLTAGE (V)
9
112935 G20
0
–50
–25
50
25
0
75
TEMPERATURE (°C)
100
125
112935 G21
112935ff
7
LT1129/LT1129-3.3/LT1129-5
TYPICAL PERFORMANCE CHARACTERISTICS
Reverse Output Current
Current Limit
20
15
10
5
1.2
SHORT-CIRCUIT CURRENT (A)
SHORT-CIRCUIT CURRENT (A)
1.0
0.8
0.6
0.4
0.2
0
–50
0
50
25
0
75
TEMPERATURE (°C)
–25
100
0
125
1
4
3
2
5
INPUT VOLTAGE (V)
Reverse Output Current
TJ = 25°C, VIN = 0V
VOUT = VSENSE
(LT1129-3.3/LT1129-5)
VOUT = VADJ (LT1129)
CURRENT FLOWS
INTO DEVICE
70
60
50
0.6
0.4
VIN = 7V
VOUT = 0V
0
–50
7
LT1129
LT1129-3.3
–25
50
25
0
75
TEMPERATURE (°C)
Ripple Rejection
(VIN – VOUT)AVG = 1V
VRIPPLE = 0.5VP-P
IL = 0.7A
IOUT = 500mA
VIN = 6V + 50mVRMS RIPPLE
90
80
66
64
62
60
58
LT1129-5
10
0
2
1
3 4 5 6 7 8
OUTPUT VOLTAGE (V)
9
70
COUT = 47μF
SOLID
TANTALUM
60
50
40
30
COUT = 3.3μF
SOLID
TANTALUM
10
56
–50
10
–25
50
25
0
75
TEMPERATURE (°C)
100
0
125
10
100
1k
10k
FREQUENCY (Hz)
100k
1M
112935 G27
112935 G26
112935 G25
LT1129-5
Transient Response
Load Regulation
125
112935 G24
20
20
100
100
68
40
30
0.8
Ripple Rejection
RIPPLE REJECTION (dB)
OUTPUT CURRENT (μA)
6
70
100
80
1.0
112935 G23
112935 G22
90
1.2
0.2
RIPPLE REJECTION (dB)
OUTPUT CURRENT (μA)
1.4
VOUT = 0V
VIN = 0V
VOUT = VSENSE = 5V (LT1129-5)
VOUT = VSENSE = 3.3V (LT1129-3.3)
VOUT = VADJ = 3.75V (LT1129)
25
0
Current Limit
1.4
30
LT1129-5
Transient Response
0
LT1129-5
–15
0.05
0
–0.05
–0.10
0.2
0.1
VIN = 6V
CIN = 3.3μF
COUT = 47μF
0
–0.1
–0.2
–25
–30
–50
VIN = VOUT(NOMINAL) + 1V
ΔILOAD = 1mA to 700mA
*VADJ = VOUT
–25
50
25
0
75
TEMPERATURE (°C)
100
125
112935 G28
0.6
0.5
0
50 100 150 200 250 300 350 400 450 500
TIME (μs)
112935 G29
LOAD CURRENT
(A)
0.7
–20
LOAD CURRENT
(A)
LOAD REGULATION (mV)
LT1129*
–10
VIN = 6V
CIN = 3.3μF
COUT = 3.3μF
0.10
OUTPUT VOLTAGE
DEVIATION (V)
OUTPUT VOLTAGE
DEVIATION (V)
LT1129-3.3
–5
0.5
0.3
0.1
0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0
TIME (ms)
112935 G30
112935ff
8
LT1129/LT1129-3.3/LT1129-5
PIN FUNCTIONS
Input Pin: Power is supplied to the device through the
input pin. The input pin should be bypassed to ground
if the device is more than 6 inches away from the main
input filter capacitor. In general, the output impedance of
a battery rises with frequency so it is advisable to include
a bypass capacitor in battery-powered circuits. A bypass
capacitor in the range of 1μF to 10μF is sufficient. The
LT1129 is designed to withstand reverse voltages on the
input pin with respect to both ground and the output pin.
In the case of a reversed input, which can happen if a
battery is plugged in backwards, the LT1129 will act as if
there is a diode in series with its input. There will be no
reverse current flow into the LT1129 and no reverse voltage will appear at the load. The device will protect both
itself and the load.
Output Pin: The output pin supplies power to the load. An
output capacitor is required to prevent oscillations. See
the Applications Information section for recommended
value of output capacitance and information on reverse
output characteristics.
Shutdown Pin (SHDN): This pin is used to put the device
into shutdown. In shutdown the output of the device is
turned off. This pin is active low. The device will be shut
down if the shutdown pin is actively pulled low. The
shutdown pin current with the pin pulled to ground will
be 6μA. The shutdown pin is internally clamped to 7V
and – 0.6V (one VBE). This allows the shutdown pin to be
driven directly by 5V logic or by open collector logic with
a pull-up resistor. The pull-up resistor is only required
to supply the leakage current of the open collector gate,
normally several microamperes. Pull-up current must be
limited to a maximum of 20mA. A curve of shutdown pin
input current as a function of voltage appears in the Typical
Performance Characteristics. If the shutdown pin is not
used it can be left open circuit. The device will be active,
output on, if the shutdown pin is not connected.
Sense Pin: For fixed voltage versions of the LT1129
(LT1129-3.3, LT1129-5) the sense pin is the input to the
error amplifier. Optimum regulation will be obtained at the
point where the sense pin is connected to the output pin.
For most applications the sense pin is connected directly
to the output pin at the regulator. In critical applications
small voltage drops caused by the resistance (RP) of PC
traces between the regulator and the load, which would
normally degrade regulation, may be eliminated by connecting the sense pin to the output pin at the load as
shown in Figure 1 (Kelvin Sense Connection). Note that
the voltage drop across the external PC traces will add to
the dropout voltage of the regulator. The sense pin bias
current is 15μA at the nominal regulated output voltage.
This pin is internally clamped to –0.6V (one VBE).
Adjust Pin: For the LT1129 (adjustable version) the adjust
pin is the input to the error amplifier. This pin is internally
clamped to 6V and –0.6V (one VBE). This pin has a bias
current of 150nA which flows into the pin. See Bias Current curve in the Typical Performance Characteristics. The
adjust pin reference voltage is equal to 3.75V referenced
to ground.
RP
IN
1μF
OUT
LT1129
SHDN
SENSE
GND
+
LOAD
10μF
RP
112935 F01
Figure 1. Kelvin Sense Connection
APPLICATIONS INFORMATION
The LT1129 is a micropower low dropout regulator with
shutdown, capable of supplying 700mA of output current
at a dropout voltage of 0.4V. The device operates with very
low quiescent current (50μA). In shutdown the quiescent
current drops to only 16μA. In addition to the low quiescent current the LT1129 incorporates several protection
features which make it ideal for use in battery-powered
systems. The device is protected against reverse input
voltages. In battery backup applications where the output
can be held up by a backup battery when the input is pulled
to ground, the LT1129 acts like it has a diode in series
with its output and prevents reverse current flow.
112935ff
9
LT1129/LT1129-3.3/LT1129-5
APPLICATIONS INFORMATION
Adjustable Operation
Thermal Considerations
The adjustable version of the LT1129 has an output voltage
range of 3.75V to 30V. The output voltage is set by the
ratio of two external resistors as shown in Figure 2. The
device servos the output voltage to maintain the voltage
at the adjust pin at 3.75V. The current in R1 is then equal
to 3.75V/R1. The current in R2 is equal to the sum of the
current in R1 and the adjust pin bias current. The adjust
pin bias current, 150nA at 25°C, flows through R2 into the
adjust pin. The output voltage can be calculated according
to the formula in Figure 2. The value of R1 should be less
than 400k to minimize errors in the output voltage caused
by the adjust pin bias current. Note that in shutdown the
output is turned off and the divider current will be zero.
Curves of Adjust Pin Voltage vs Temperature and Adjust
Pin Bias Current vs Temperature appear in the Typical
Performance Characteristics. The reference voltage at
the adjust pin has a positive temperature coefficient of
approximately 15ppm/°C. The adjust pin bias current has
a negative temperature coefficient. These effects are small
and will tend to cancel each other.
The power handling capability of the device will be limited
by the maximum rated junction temperature (125°C). The
power dissipated by the device will be made up of two
components:
The adjustable device is specified with the adjust pin tied
to the output pin. This sets the output voltage to 3.75V.
Specifications for output voltages greater than 3.75V will
be proportional to the ratio of the desired output voltage
to 3.75V (VOUT/3.75V). For example: load regulation for an
output current change of 1mA to 700mA is – 6mV typical at
VOUT = 3.75V. At VOUT = 12V, load regulation would be:
12V
3.75V • ( –6mV ) = ( –19mV )
IN
VOUT
OUT
LT1129
SHDN
R2
ADJ
+
R1
GND
112935 F02
(
)
VOUT = 3.75V 1 + R2 + IADJ • R2
R1
VADJ = 3.75V
IADJ = 150nA at 25°C
OUTPUT RANGE = 3.75V to 30V
(
)
Figure 2. Adjustable Operation
1. Output current multiplied by the input/output voltage
differential: IOUT • (VIN – VOUT), and
2. Ground pin current multiplied by the input voltage:
IGND • VIN.
The ground pin current can be found by examining the
Ground Pin Current curves in the Typical Performance
Characteristics. Power dissipation will be equal to the
sum of the two components listed above.
The LT1129 series regulators have internal thermal
limiting designed to protect the device during overload
conditions. For continuous normal load conditions the
maximum junction temperature rating of 125°C must not
be exceeded. It is important to give careful consideration
to all sources of thermal resistance from junction to ambient. Additional heat sources mounted nearby must also be
considered.
For surface mount devices heat sinking is accomplished
by using the heat spreading capabilities of the PC board
and its copper traces. Experiments have shown that the
heat spreading copper layer does not need to be electrically connected to the tab of the device. The PC material
can be very effective at transmitting heat between the pad
area, attached to the tab of the device, and a ground or
power plane layer either inside or on the opposite side of
the board. Although the actual thermal resistance of the
PC material is high, the length/area ratio of the thermal
resistor between layers is small. Copper board stiffeners
and plated through holes can also be used to spread the
heat generated by power devices.
The following tables list thermal resistances for each
package. For the TO-220 package, thermal resistance
is given for junction-to-case only since this package
is usually mounted to a heat sink. Measured values of
thermal resistance for several different board sizes and
copper areas are listed for each package. All measurements were taken in still air on 3/32" FR-4 board with 1-oz
112935ff
10
LT1129/LT1129-3.3/LT1129-5
OPERATION
copper. This data can be used as a rough guideline in
estimating thermal resistance. The thermal resistance for
each application will be affected by thermal interactions
with other components as well as board size and shape.
Some experimentation will be necessary to determine the
actual value.
where, IOUT MAX = 500mA
VIN MAX = 5.5V
IGND at (IOUT = 500mA, VIN = 5.5V) = 25mA
Table 1. Q Package, 5-Lead DD
so,
COPPER AREA
TOPSIDE*
BACKSIDE
THERMAL RESISTANCE
BOARD AREA (JUNCTION-TO-AMBIENT)
2500 sq. mm 2500 sq. mm
2500 sq. mm
25°C/W
1000 sq. mm 2500 sq. mm
2500 sq. mm
27°C/W
125 sq. mm
2500 sq. mm
35°C/W
2500 sq. mm
* Tab of device attached to topside copper
COPPER AREA
BACKSIDE
THERMAL RESISTANCE
BOARD AREA (JUNCTION-TO-AMBIENT)
2500 sq. mm 2500 sq. mm
2500 sq. mm
45°C/W
1000 sq. mm 2500 sq. mm
2500 sq. mm
45°C/W
225 sq. mm
2500 sq. mm
2500 sq. mm
53°C/W
100 sq. mm
2500 sq. mm
2500 sq. mm
59°C/W
* Tab of device attached to topside copper
Table 3. S8 Package, 8-Lead Plastic SOIC
COPPER AREA
TOPSIDE*
BACKSIDE
IOUT MAX • (VIN MAX – VOUT) + (IGND • VIN MAX)
P = 500mA • (5.5V – 3.3V) + (25mA • 5.5V)
= 1.24W
If we use a DD package, then the thermal resistance will be
in the range of 25°C/W to 35°C/W depending on copper
area. So the junction temperature rise above ambient will
be approximately equal to:
1.24W • 30°C/W = 37.2°C
Table 2. ST Package, 3-Lead SOT-223
TOPSIDE*
The power dissipated by the device will be equal to:
THERMAL RESISTANCE
BOARD AREA (JUNCTION-TO-AMBIENT)
2500 sq. mm 2500 sq. mm
2500 sq. mm
55°C/W
1000 sq. mm 2500 sq. mm
2500 sq. mm
55°C/W
225 sq. mm
2500 sq. mm
2500 sq. mm
63°C/W
100 sq. mm
2500 sq. mm
2500 sq. mm
69°C/W
* Device attached to topside copper
The maximum junction temperature will then be equal to
the maximum junction temperature rise above ambient
plus the maximum ambient temperature or:
TJMAX = 50°C + 37.2°C = 87.2°C
Output Capacitance and Transient Performance
The LT1129 is designed to be stable with a wide range
of output capacitors. The minimum recommended value
is 3.3μF with an ESR of 2Ω or less. The LT1129 is a
micropower device and output transient response will
be a function of output capacitance. See the Transient
Response curves in the Typical Performance Characteristics. Larger values of output capacitance will decrease
the peak deviations and provide improved output transient
response. Bypass capacitors, used to decouple individual
components powered by the LT1129, will increase the
effective value of the output capacitor.
T Package, 5-Lead TO-220
Thermal Resistance (Junction-to-Case) = 5°C/W
Protection Features
Calculating Junction Temperature
The LT1129 incorporates several protection features
which make it ideal for use in battery-powered circuits.
In addition to the normal protection features associated
with monolithic regulators, such as current limiting and
thermal limiting, the device is protected against reverse
input voltages, and reverse voltages from output to input.
For fixed voltage devices the output and sense pins are
tied together at the output.
Example: Given an output voltage of 3.3V, an input voltage
range of 4.5V to 5.5V, an output current range of 0mA to
500mA, and a maximum ambient temperature of 50°C,
what will the maximum junction temperature be?
112935ff
11
LT1129/LT1129-3.3/LT1129-5
APPLICATIONS INFORMATION
Current limit protection and thermal overload protection
are intended to protect the device against current overload
conditions at the output of the device. For normal operation,
the junction temperature should not exceed 125°C.
The input of the device will withstand reverse voltages
of 30V. Current flow into the device will be limited to less
than 1mA (typically less than 100μA) and no negative
voltage will appear at the output. The device will protect
both itself and the load. This provides protection against
batteries that can be plugged in backwards.
For fixed voltage versions of the device, the sense pin
is internally clamped to one diode drop below ground.
For the adjustable version of the device, the output pin
is internally clamped at one diode drop below ground. If
the output pin of an adjustable device, or the sense pin
of a fixed voltage device, is pulled below ground, with the
input open or grounded, current must be limited to less
than 5mA.
In circuits where a backup battery is required, several
different input /output conditions can occur. The output
voltage may be held up while the input is either pulled
to ground, pulled to some intermediate voltage, or is left
open circuit. Current flow back into the output will vary
depending on the conditions. Many battery-powered
circuits incorporate some form of power management.
The following information will help optimize battery life.
Table 4 summarizes the following information.
The reverse output current will follow the curve in Figure 3
when the input pin is pulled to ground. This current flows
through the output pin to ground. The state of the shutdown
pin will have no effect on output current when the input
pin is pulled to ground.
In some applications it may be necessary to leave the
input to the LT1129 unconnected when the output is held
high. This can happen when the LT1129 is powered from
a rectified AC source. If the AC source is removed, then
the input of the LT1129 is effectively left floating. The
reverse output current also follows the curve in Figure 3
if the input pin is left open. The state of the shutdown pin
will have no effect on the reverse output current when the
input pin is floating.
When the input of the LT1129 is forced to a voltage below
its nominal output voltage and its output is held high, the
reverse output current will still follow the curve shown
in Figure 3. This can happen if the input of the LT1129 is
connected to a discharged (low voltage) battery and the
output is held up by either a backup battery or by a second
regulator circuit.
When the input pin is forced below the output pin or the
output pin is pulled above the input pin, the input current will
typically drop to less than 2μA (see Figure 4). The state of
the shutdown pin will have no effect on the reverse output
current when the output is pulled above the input.
5
TJ = 25°C
90 VIN = 0V
VSENSE = VOUT
80
CURRENT FLOWS
70 INTO DEVICE
60
LT1129
50
40
LT1129-3.3
30
3
2
1
20
LT1129-5
10
0
VOUT = 3.3V (LT1129-3.3)
VOUT = 5V (LT1129-5)
4
INPUT CURRENT (μA)
OUTPUT PIN CURRENT (μA)
100
0
0
1
2
3 4 5 6 7 8
OUTPUT VOLTAGE (V)
9
10
112935 F03
Figure 3. Reverse Output Current
0
1
3
2
INPUT VOLTAGE (V)
4
5
112935 F04
Figure 4. Input Current
112935ff
12
LT1129/LT1129-3.3/LT1129-5
APPLICATIONS INFORMATION
Table 4. Fault Conditions
INPUT PIN
SHDN PIN
OUTPUT PIN
< VOUT (Nominal)
Open (Hi)
Forced to VOUT (Nominal)
Reverse Output Current ≈ 15μA (See Figure 3)
Input Current ≈ 1μA (See Figure 4)
< VOUT (Nominal)
Grounded
Forced to VOUT (Nominal)
Reverse Output Current ≈ 15μA (See Figure 3)
Input Current ≈ 1μA (See Figure 4)
Open
Open (Hi)
Forced to VOUT (Nominal)
Reverse Output Current ≈ 15μA (See Figure 3)
Open
Grounded
Forced to VOUT (Nominal)
Reverse Output Current ≈ 15μA (See Figure 3)
PACKAGE DESCRIPTION
F Package
20-Lead Plastic TSSOP (4.4mm)
(LTC DWG # 05-08-1650)
6.40 – 6.60*
(.252 – .260)
1.05 ±0.10
6.60 ±0.10
20 19 18 17 16 15 14 13 12 11
4.50 ±0.10
0.45 ±0.05
6.40
(.252)
BSC
0.65 BSC
1 2 3 4 5 6 7 8 9 10
RECOMMENDED SOLDER PAD LAYOUT
4.30 – 4.50**
(.169 – .177)
0.09 – 0.20
(.0035 – .0079)
0.25
REF
1.10
(.0433)
MAX
0° – 8°
0.65
(.0256)
BSC
0.50 – 0.75
(.020 – .030)
NOTE:
1. CONTROLLING DIMENSION: MILLIMETERS
MILLIMETERS
2. DIMENSIONS ARE IN
(INCHES)
0.19 – 0.30
(.0075 – .0118)
TYP
0.05 – 0.15
(.002 – .006)
F20 TSSOP 0204
3. DRAWING NOT TO SCALE
*DIMENSIONS DO NOT INCLUDE MOLD FLASH. MOLD FLASH
SHALL NOT EXCEED .152mm (.006") PER SIDE
OBSOLETE PACKAGE
112935ff
Information furnished by Linear Technology Corporation is believed to be accurate and reliable.
However, no responsibility is assumed for its use. Linear Technology Corporation makes no representation that the interconnection of its circuits as described herein will not infringe on existing patent rights.
13
LT1129/LT1129-3.3/LT1129-5
PACKAGE DESCRIPTION
Q Package
5-Lead Plastic DD Pak
(LTC DWG # 05-08-1461)
.256
(6.502)
.060
(1.524)
TYP
.060
(1.524)
.390 – .415
(9.906 – 10.541)
.165 – .180
(4.191 – 4.572)
.045 – .055
(1.143 – 1.397)
15° TYP
.060
(1.524)
.183
(4.648)
+.008
.004 –.004
+0.203
0.102 –0.102
.059
(1.499)
TYP
.330 – .370
(8.382 – 9.398)
(
)
.095 – .115
(2.413 – 2.921)
.075
(1.905)
.300
(7.620)
+.012
.143 –.020
+0.305
3.632 –0.508
(
BOTTOM VIEW OF DD PAK
HATCHED AREA IS SOLDER PLATED
COPPER HEAT SINK
.067
(1.702)
.028 – .038 BSC
(0.711 – 0.965)
TYP
)
Q(DD5) 0502
.420
.276
.080
.420
.050 ± .012
(1.270 ± 0.305)
.013 – .023
(0.330 – 0.584)
.325
.350
.205
.565
.565
.320
.090
.090
.067
.042
RECOMMENDED SOLDER PAD LAYOUT
NOTE:
1. DIMENSIONS IN INCH/(MILLIMETER)
2. DRAWING NOT TO SCALE
.067
.042
RECOMMENDED SOLDER PAD LAYOUT
FOR THICKER SOLDER PASTE APPLICATIONS
112935ff
14
Information furnished by Linear Technology Corporation is believed to be accurate and reliable.
However, no responsibility is assumed for its use. Linear Technology Corporation makes no representation that the interconnection of its circuits as described herein will not infringe on existing patent rights.
LT1129/LT1129-3.3/LT1129-5
PACKAGE DESCRIPTION
S8 Package
8-Lead Plastic Small Outline (Narrow 0.150)
(LTC DWG # 05-08-1610)
.189 – .197
(4.801 – 5.004)
NOTE 3
.045 ±.005
.050 BSC
8
.245
MIN
.160 ±.005
7
6
5
.053 – .069
(1.346 – 1.752)
.150 – .157
(3.810 – 3.988)
NOTE 3
.228 – .244
(5.791 – 6.197)
.030 ±.005
TYP
1
2
3
INCHES
(MILLIMETERS)
2. DRAWING NOT TO SCALE
.050
(1.270)
BSC
.014 – .019
(0.355 – 0.483)
TYP
.010 – .020
s 45°
(0.254 – 0.508)
4
RECOMMENDED SOLDER PAD LAYOUT
NOTE:
1. DIMENSIONS IN
.004 – .010
(0.101 – 0.254)
.008 – .010
(0.203 – 0.254)
0°– 8° TYP
3. THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS.
MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED .006" (0.15mm)
.016 – .050
(0.406 – 1.270)
SO8 0303
ST Package
3-Lead Plastic SOT-223
(LTC DWG # 05-08-1630)
.248 – .264
(6.30 – 6.71)
.129 MAX
.114 – .124
(2.90 – 3.15)
.059 MAX
.264 – .287
(6.70 – 7.30)
.248 BSC
.130 – .146
(3.30 – 3.71)
.039 MAX
.059 MAX
.181 MAX
.033 – .041
(0.84 – 1.04)
.0905
(2.30)
BSC
RECOMMENDED SOLDER PAD LAYOUT
10° – 16°
.010 – .014
(0.25 – 0.36)
10°
MAX
.071
(1.80)
MAX
.090
BSC
10° – 16°
.024 – .033
(0.60 – 0.84)
.181
(4.60)
BSC
.012
(0.31)
MIN
.0008 – .0040
(0.0203 – 0.1016)
ST3 (SOT-233) 0502
112935ff
Information furnished by Linear Technology Corporation is believed to be accurate and reliable.
However, no responsibility is assumed for its use. Linear Technology Corporation makes no representation that the interconnection of its circuits as described herein will not infringe on existing patent rights.
15
LT1129/LT1129-3.3/LT1129-5
TYPICAL APPLICATION
T Package
5-Lead Plastic TO-220 (Standard)
(LTC DWG # 05-08-1421)
.165 – .180
(4.191 – 4.572)
.147 – .155
(3.734 – 3.937)
DIA
.390 – .415
(9.906 – 10.541)
.045 – .055
(1.143 – 1.397)
.230 – .270
(5.842 – 6.858)
.570 – .620
(14.478 – 15.748)
.460 – .500
(11.684 – 12.700)
.330 – .370
(8.382 – 9.398)
.620
(15.75)
TYP
.700 – .728
(17.78 – 18.491)
SEATING PLANE
.152 – .202
.260 – .320 (3.861 – 5.131)
(6.60 – 8.13)
.095 – .115
(2.413 – 2.921)
.155 – .195*
(3.937 – 4.953)
.013 – .023
(0.330 – 0.584)
BSC
.067
(1.70)
.028 – .038
(0.711 – 0.965)
.135 – .165
(3.429 – 4.191)
* MEASURED AT THE SEATING PLANE
T5 (TO-220) 0801
RELATED PARTS
PART NUMBER
DESCRIPTION
COMMENTS
LT1121
150mA LDO Micropower Regulator
30μA IQ, SOT-223 Package
LT1761
100mA Low Noise, LDO Micropower Regulator
20μA IQ, 20μVRMS Noise
LT1762
150mA Low Noise, LDO Micropower Regulator
25μA IQ, 20μVRMS Noise
LT1962
300mA Low Noise, LDO Micropower Regulator
30μA IQ, 20μVRMS Noise
LT1763
500mA Low Noise, LDO Micropower Regulator
30μA IQ, 20μRMS Noise
LT1963
1.5A Low Noise, Fast Transient, LDO Regulator
340mV Dropout Voltage, 40μVRMS Noise
LT1764
3A Low Noise, Fast Transient, LDO Regulator
340mV Dropout Voltage, 40μVRMS Noise
112935ff
16 Linear Technology Corporation
LT 1208 REV F • PRINTED IN USA
1630 McCarthy Blvd., Milpitas, CA 95035-7417
(408) 432-1900 ● FAX: (408) 434-0507
●
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