LM337T [Linear]
Negative Adjustable Regulator; 负可调稳压器
| 型号： | LM337T |
| 厂家： | 
Linear |
| 描述： | Negative Adjustable Regulator |
| 文件： | 总12页 (文件大小：157K) |
| 中文： | 中文翻译 | 下载： | 下载PDF数据表文档文件 |
LT137A/LM137
LT337A/LM337
Negative Adjustable
Regulator
FEATURES
DESCRIPTION
The LT®137A/LT337A negative adjustable regulators will
deliver up to 1.5A output current over an output voltage
range of –1.2V to –37V. Linear Technology has made
significantimprovementsintheseregulatorscomparedto
previous devices, such as better line and load regulation,
and a maximum output voltage error of 1%.
n
Guaranteed 1% Initial Voltage Tolerance
n
Guaranteed 0.01%/V Line Regulation
n
Guaranteed 0.5% Load Regulation
Guaranteed 0.02%/W Thermal Regulation
n
n
100% Burn-in in Thermal Limit
APPLICATIONS
Every effort has been made to make these devices easy
to use and difficult to damage. Internal current and power
limitingcoupledwithtruethermallimitingpreventsdevice
damage due to overloads or shorts, even if the regulator
is not fastened to a heat sink.
n
Adjustable Power Supplies
n
System Power Supplies
n
Precision Voltage/Current Regulators
n
On-Card Regulators
Maximum reliability is attained with Linear Technology’s
advanced processing techniques combined with a 100%
burn-in in the thermal limit mode. This assures that all
device protection circuits are working and eliminates field
failuresexperiencedwithotherregulatorsthatreceiveonly
standard electrical testing.
L, LT, LTC and LTM are registered trademarks of Linear Technology Corporation. All other
trademarks are the property of their respective owners.
TYPICAL APPLICATION
Negative Regulator
Output Voltage Error
12
1% RESISTORS
2% RESISTORS
11
10
9
R2*
+
+
C2
5μF
C3
1μF
SOLID
TANTALUM
SOLID
TANTALUM
R1
121Ω
8
7
LM337
ADJ
6
R2
R1
–V
V
LT137A
V
–V
= 1.25V 1 +
OUT
OUT
IN
IN
ꢀ
ꢁ
5
4
LT337A
137A TA01
3
|
V
|
OUT
2
*R2 = R1
– 1
ꢀ
ꢁ
1.25V
1
0
1
2
4
6
8 10
20
40
100
OUTPUT VOLTAGE (V)
137A TA01b
137afb
1
LT137A/LM137
LT337A/LM337
ABSOLUTE MAXIMUM RATINGS
(Note 1)
Power Dissipation.......................…….Internally Limited
Input to Output Voltage Differential..................…….40V
Operating Junction Temperature Range
PRECONDITIONING
100% Thermal Limit Burn-In
LT137A/LM137 .................................. –55°C to 150°C
LT337A/LM337 ...................................... 0°C to 125°C
Storage Temperature Range
LT137A/LM137 .................................. –65°C to 150°C
LT337A/LM337 .................................. –65°C to 150°C
Lead Temperature (Soldering, 10 sec.) ................. 300°C
PIN CONFIGURATION
BOTTOM VIEW
ADJ
BOTTOM VIEW
V
OUT
CASE IS INPUT
2
1
1
2
3
CASE
IS V
V
OUT
IN
ADJ
V
IN
K PACKAGE
H PACKAGE
3-LEAD TO-39 METAL CAN
= 150°C/W, θ = 15°C/W
2-LEAD TO-3 METAL CAN
θ
JA
= 35°C/W, θ = 3°C/W
JC
θ
JA
JC
OBSOLETE PACKAGE
OBSOLETE PACKAGE
Consider the M and T Packages for Alternate Source
Consider the M and T Packages for Alternate Source
FRONT VIEW
TAB IS
INPUT
FRONT VIEW
3
2
1
V
V
OUT
3
2
1
V
V
OUT
IN
TAB
IS
INPUT
IN
ADJ
ADJ
M PACKAGE
T PACKAGE
3-LEAD PLASTIC DD
3-LEAD PLASTIC TO-220
θ
= 30°C/W, θ = 3°C/W
JA
JC
θ
JA
= 50°C/W, θ = 4°C/W
JC
ORDER INFORMATION
LEAD FREE FINISH
LT337AM#PBF
LT337AT#PBF
LM337T#PBF
LEAD BASED FINISH
LT337AM
TAPE AND REEL
LT337AM#TRPBF
LT337AT#TRPBF
LM337T#TRPBF
TAPE AND REEL
LT337AM#TR
PART MARKING*
LT337AM
PACKAGE DESCRIPTION
3-Lead Plastic DD
TEMPERATURE RANGE
0°C to 125°C
LT337AT
3-Lead Plastic TO-220
3-Lead Plastic TO-220
PACKAGE DESCRIPTION
3-Lead Plastic DD
0°C to 125°C
LM337T
0°C to 125°C
PART MARKING*
LT337AM
TEMPERATURE RANGE
0°C to 125°C
LT337AT
LT337AT#TR
LT337AT
3-Lead Plastic TO-220
0°C to 125°C
137afb
2
LT137A/LM137
LT337A/LM337
ORDER INFORMATION
LEAD BASED FINISH
TAPE AND REEL
PART MARKING
PACKAGE DESCRIPTION
TEMPERATURE RANGE
LM337T
LM337T#TR
LM337T
3-Lead Plastic TO-220
0°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.
Consult LTC Marketing for information on non-standard lead based finish parts.
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. (Notes 2, 3)
LT137A
TYP
LM137
TYP
SYMBOL PARAMETER
Reference Voltage
CONDITIONS
– V = 5V, I
MIN
MAX
MIN
MAX
UNITS
V
|
V
|
= 10mA, T = 25°C
–1.238 –1.250 –1.262 –1.225 –1.250 –1.275
–1.220 –1.250 –1.280 –1.200 –1.250 –1.300
V
V
REF
IN
OUT
OUT
j
l
3V ≤
|
V
– V
OUT
|
≤ 40V
MAX
IN
OUT
10mA ≤ I
≤ I
≤ I
, P ≤ P
MAX
ΔV
OUT
OUT
Load Regulation
10mA ≤ I
, (Note 4)
OUT
MAX
ΔI
T = 25°C,
|
|
|
|
V
V
V
V
|
|
|
|
≤ 5V
≥ 5V
≤ 5V
≥ 5V
5
25
0.5
50
1
15
0.3
20
25
0.5
50
1
mV
%
j
OUT
OUT
OUT
OUT
T = 25°C,
j
0.1
10
0.2
l
l
mV
%
0.3
ΔV
ΔV
Line Regulation
Ripple Rejection
3V ≤
|
V
j
– V
| ≤ 40V (Note 4)
OUT
IN
OUT
T = 25°C
0.005
0.01
0.01
0.03
0.01
0.02
0.02
0.05
%/V
%/V
IN
l
V
OUT
= –10V, f = 120Hz
C
C
= 0
= 10μF
60
70
66
80
60
77
dB
dB
ADJ
ADJ
l
l
66
Thermal Regulation
Adjust Pin Current
T = 25°C, 10ms Pulse
j
0.002
65
0.02
100
0.002
65
0.02
100
%/W
μA
I
ADJ
l
l
ΔI
Adjust Pin Current Change
10mA ≤ I
≤ I
0.2
1
2
5
0.5
2
5
5
μA
μA
ADJ
OUT
– V
MAX
| ≤ 40V
3V ≤
|V
IN
OUT
l
l
Minimum Load Current
Current Limit
|
|
|
V
V
V
– V
– V
– V
|
|
|
≤ 40V
≤ 10V
≤ 15V,
2.5
1.2
5
3
2.5
1.2
5
3
mA
mA
IN
IN
IN
OUT
OUT
OUT
I
SC
l
l
K and T Package (Note 7)
H Package
1.5
0.5
2.2
0.8
1.5
0.5
2.2
0.8
A
A
|V
– V
| = 40V,
IN
OUT
K and T Package
H Package
0.24
0.15
0.4
0.25
0.24
0.15
0.4
0.25
A
A
T = 25°C
j
l
ΔV
ΔTemp
Temperature Stability of
Output Voltage (Note 6)
T
≤ T ≤ T
MAX
0.6
0.3
1.5
1
0.6
0.3
%
%
%
OUT
MIN
ΔV
OUT
Long Term Stability
T = 125°C, 1000 Hours
A
1
ΔTime
e
RMS Output Noise
T = 25°C, 10Hz ≤ f ≤ 10kHz
A
0.003
0.003
n
(% of V
)
OUT
Thermal Resistance Junction H Package
to Case K Package
12
2.3
15
3
12
2.3
15
3
°C/W
°C/W
θ
JC
137afb
3
LT137A/LM137
LT337A/LM337
ELECTRICAL CHARACTERISTICS The l denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at TA = 25°C. (Notes 2, 3)
LT337A
TYP
LM337
TYP
SYMBOL PARAMETER
Reference Voltage
CONDITIONS
– V = 5V, I
MIN
MAX
MIN
MAX
UNITS
V
|V
|
= 10mA, T = 25°C
–1.238 –1.250 –1.262 –1.213 –1.250 –1.287
–1.220 –1.250 –1.280 –1.200 –1.250 –1.300
V
V
REF
IN
OUT
OUT
j
l
3V ≤
|
V
– V
OUT
|
≤ 40V
MAX
IN
OUT
10mA ≤ I
≤ I
≤ I
, P ≤ P
MAX
ΔV
OUT
OUT
Load Regulation
10mA ≤ I
, (Notes 4 and 5)
OUT
MAX
ΔI
T = 25°C,
|V
|V
|V
|V
|
|
|
|
≤ 5V
≥ 5V
≤ 5V
≥ 5V
5
25
0.5
50
1
15
0.3
20
50
1
mV
%
j
OUT
OUT
OUT
OUT
T = 25°C,
j
0.1
10
0.2
l
l
70
1.5
mV
%
0.3
ΔV
ΔV
Line Regulation
Ripple Rejection
3V ≤
|
V
j
– V
| ≤ 40V (Note 4)
OUT
IN
OUT
T = 25°C
0.005
0.01
0.01
0.03
0.01
0.02
0.04
0.07
%/V
%/V
IN
l
V
OUT
= –10V, f = 120Hz
C
C
= 0
= 10μF
60
70
66
80
60
77
dB
dB
ADJ
ADJ
l
l
66
Thermal Regulation
Adjust Pin Current
T = 25°C, 10ms Pulse
j
0.002
65
0.02
100
0.003
65
0.04
100
%/W
μA
I
ADJ
l
l
ΔI
Adjust Pin Current Change
10mA ≤ I
≤ I
0.2
1
2
5
0.5
2
5
5
μA
μA
ADJ
OUT
– V
MAX
| ≤ 40V
3V ≤
|
V
IN
OUT
l
l
Minimum Load Current
Current Limit
|
|
|
V
V
V
– V
– V
– V
|
|
|
≤ 40V
≤ 10V
≤ 15V,
2.5
1.2
5
3
2.5
1
10
6
mA
mA
IN
IN
IN
OUT
OUT
OUT
I
SC
l
l
K, M and T Package
H Package
1.5
0.5
2.2
0.8
1.5
0.5
2.2
0.8
A
A
|V
– V
| = 40V,
OUT
IN
K, M and T Package
H Package
0.24
0.15
0.5
0.25
0.15
0.1
0.4
0.17
A
A
T = 25°C
j
l
ΔV
ΔTemp
Temperature Stability of
Output Voltage (Note 6)
0.6
0.3
1.5
1
0.6
0.3
%
%
%
OUT
ΔV
OUT
Long Term Stability
T = 125°C, 1000 Hours
1
A
ΔTime
e
RMS Output Noise
T = 25°C, 10Hz ≤ f ≤ 10kHz
A
0.003
0.003
n
(% of V
)
OUT
Thermal Resistance Junction H Package
12
2.3
3
15
3
5
12
2.3
3
15
3
5
°C/W
°C/W
°C/W
θ
JC
to Case
K Package
M and T Package
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 shaded electrical specifications indicate those parameters
which have been improved or guaranteed test limits provided for the first
time.
Note 4: Testing is done using a pulsed low duty cycle technique. See
thermal regulation specifications for output changes due to heating effects.
Load regulation is measured on the output pin at a point 1/8" below the
base of the K and H package and at the junction of the wide and narrow
portion of the lead on the M and T package.
Note 5: Load regulation for the LT337AT is the same as for LM337T.
Note 6: Guaranteed on LT137A and LT337A, but not 100% tested in
Note 3: Unless otherwise indicated, these specifications apply:
|
V
production.
IN
– V = 5V; and I = 0.1A for the H package, I = 0.5A for the K, M,
|
OUT
OUT
OUT
Note 7: I is tested at the ambient temperatures of 25°C and –55°C. I
SC
SC
and T packages. Power dissipation is internally limited. However, these
specifications apply for power dissipation up to 2W for the H package and
cannot be tested at the maximum ambient temperature of 150°C due to the
high power level required. I specification at 150°C ambient is guaranteed
by characterization and correlation to 25°C testing.
SC
20W for the K and T packages. I
and 0.2A for the H package.
= 1.5A for the K, M, and T packages,
MAX
137afb
4
LT137A/LM137
LT337A/LM337
TYPICAL PERFORMANCE CHARACTERISTICS
Dropout Voltage
Temperature Stability
Minimum Load Current
3.0
2.6
2.2
1.8
1.4
1.0
1.270
1.260
1.250
1.240
1.230
1.8
1.6
1.4
1.2
1.0
0.8
0.6
0.4
0.2
0
T = –55°C
j
T = –55°C
j
T = 25°C
j
T = 25°C
j
T = 150°C
j
T = 150°C
j
0
0.4
0.8
1.2
1.6
2.0
–75 –50 –25
0
25 50 75 100 125 150
0
10
20
30
40
OUTPUT CURRENT (A)
TEMPERATURE (°C)
INPUT-OUTPUT DIFFERENTIAL (V)
137A G01
137A G02
137A G03
Ripple Rejection
Ripple Rejection
Ripple Rejection
100
80
60
40
20
0
100
80
60
40
20
0
100
80
60
40
20
0
C
= –10μF
= 0
ADJ
ADJ
C
ADJ
= 10μF
C
C = 0
ADJ
C
= 10μF
ADJ
C
ADJ
= 0
|V – V | = 5V
V
V
L
= –15V
= –10V
= 500mA
V
V
= –15V
IN
OUT
IN
OUT
IN
OUT
I
= 500mA
= –10V
L
f = 120Hz
T = 25°C
I
f = 120Hz
T = 25°C
T = 25°C
j
j
j
0
–10
–20
–30
–40
10
100
1k
10k
100k
1M
0.01
0.1
1
10
OUTPUT VOLTAGE (V)
FREQUENCY (Hz)
OUTPUT CURRENT (A)
137A G04
137A G05
137A G06
137afb
5
LT137A/LM137
LT337A/LM337
TYPICAL PERFORMANCE CHARACTERISTICS
Output Impedance
Line Transient Response
Load Transient Response
1
0
0.6
0.4
10
10
0.8
0.6
0.4
0.2
0
V
V
L
C
= –15V
IN
OUT
= –10V
C
ADJ
= 0
I
= 500mA
= 1μF
0.2
L
C
ADJ
= 0
T = 25°C
j
0
C
ADJ
= 10μF
–0.2
–0.4
–0.6
0
–1
–2
–3
10
10
10
C
ADJ
= 10μF
C
ADJ
= 0
–0.2
–0.4
0
V
V
NL
C
= –15V
IN
OUT
V = –10V
OUT
= –10V
C
= 10μF
100k
ADJ
–0.5
–1.0
–1.5
I
= 50mA
L
I
= 50mA
= 1μF
L
C
= 1μF
L
–0.5
–1.0
T = 25°C
j
T = 25°C
j
0
10
20
TIME (μs)
30
40
10
100
1k
10k
1M
0
10
20
TIME (μs)
30
40
FREQUENCY (Hz)
137A G09
137A G07
137A G08
Load Regulation*
Current Limit
Adjustment Current
3
2
1
0
80
75
70
65
60
55
50
T = –55°C
j
0.4
0.2
T = 25°C
j
T = 150°C
j
M, T AND K
PACKAGES
0
–0.2
–0.4
H
PACKAGE
0
0.4
0.8
1.2
1.6
2.0
0
10
20
30
40
–75 –50 –25
0
25 50 75 100 125 150
OUTPUT CURRENT (A)
INPUT-OUTPUT DIFFERENTIAL (V)
TEMPERATURE (°C)
137A G10
137A G11
137A G12
*THE LT137A/LT337A HAS LOAD REGULATION
COMPENSATION WHICH MAKES THE TYPICAL
UNIT READ CLOSE TO ZERO. THIS BAND
REPRESENTS THE TYPICAL PRODUCTION
SPREAD.
137afb
6
LT137A/LM137
LT337A/LM337
APPLICATIONS INFORMATION
Output Voltage
EXAMPLES:
The output voltage is determined by two external resis-
tors, R1 and R2 (see Figure 1). The exact formula for the
output voltage is:
1. A precision 10V regulator to supply up to 1A load
current.
a. Select R1 = 100Ω to minimize effect of I
b. Calculate R2 =
ADJ
R2
R1
⎛
⎝
⎞
VOUT = VREF 1+
+I
R2
ADJ ( )
⎜
⎟
⎠
VOUT – VREF
VREF
+IADJ
R1
10V –1.25V
1.25V
+ 65μA
100Ω
=
= 696.4Ω
Where: V = Reference Voltage, I = Adjustment Pin
REF
ADJ
Current. In most applications, the second term is small
enough to be ignored, typically about 0.5% of V . In
OUT
Use R2 = 698Ω
more critical applications, the exact formula should be
used, with I equal to 65μA. Solving for R2 yields:
ADJ
2. A 15V regulator to run off batteries and supply
50mA. V = 25V
IN MAX
V
VREF
OUT – VREF
R2=
a. To minimize battery drain, select R1 as high as
possible
+IADJ
R1
1.25V
3mA
Smaller values of R1 and R2 will reduce the influence
of I on the output voltage, but the no-load current
R1=
= 417Ω, use 402Ω, 1%
ADJ
drain on the regulator will be increased. Typical values
for R1 are between 100Ω and 300Ω, giving 12.5mA and
4.2mA no-load current respectively. There is an additional
consideration in selecting R1, the minimum load current
specification of the regulator. The operating current of the
LT137A flows from input to output. If this current is not
absorbed by the load, the output of the regulator will rise
above the regulated value. The current drawn by R1 and
R2 is normally high enough to absorb the current, but
care must be taken in no-load situations where R1 and
R2 have high values.
b. The high value for R1 will exaggerate the error due
ADJ
be used.
to I , so the exact formula to calculate R2 should
VOUT – VREF
VREF
+IADJ
R1
15V –1.25V
1.25V
+ 65μA
402Ω
R2=
=
= 4331Ω
Use R2 = 4320Ω
Capacitors and Protection Diodes
An output capacitor, C3, is required to provide proper fre-
quencycompensationoftheregulatorfeedbackloop.A1μF
orlargersolidtantalumcapacitorisgenerallysufficientfor
this purpose if the 1MHz impedance of the capacitor is 2Ω
or less. High Q capacitors, such as Mylar, are not recom-
mended because they tend to reduce the phase margin at
light load currents. Aluminum electrolytic capacitors may
also be used, but the minimum value should be 10μF to
ensure a low impedance at 1MHz. The output capacitor
should be located within a few inches of the regulator to
keepleadimpedancetoaminimum. Thefollowingcaution
should be noted: if the output voltage is greater than 6V
and an output capacitor greater than 20μF has been used,
it is possible to damage the regulator if the input voltage
137afb
Themaximumvaluefortheoperatingcurrent, whichmust
be absorbed, is 5mA for the LT137A. If input-output volt-
age differential is less than 10V, the operating current that
must be absorbed drops to 3mA.
+
C1
R2
10μF
+
+
I
ADJ
C2
5μF
C3
1μF
V
REF
R1
ADJ
–V
V
LT137A
V
OUT
–V
OUT
IN
IN
137A F01
Figure 1
7
LT137A/LM137
LT337A/LM337
APPLICATIONS INFORMATION
becomes shorted, due to the output capacitor discharging
intotheregulator.Thiscanbepreventedbyusingthediode
D1 (see Figure 2) between the input and the output.
Proper Connection of Divider Resistors
The LT137A has an excellent load regulation specification
of 0.5% and is measured at a point 1/8" from the bottom
of the package. To prevent degradation of load regulation,
theresistorswhichsetoutputvoltage, R1andR2, mustbe
connectedasshowninFigure3. Notethatthepositiveside
of the load has a true force and sense (Kelvin) connection,
but the negative side of the load does not.
The input capacitor, C2, is only required if the regulator is
more than 4 inches from the raw supply filter capacitor.
Bypassing the Adjustment Pin
The adjustment pin of the LT137A may be bypassed with a
capacitortoground,C1,toreduceoutputripple,noise,and
impedance. These parameters scale directly with output
voltage if the adjustment pin is not bypassed. A bypass
capacitor reduces ripple, noise, and impedance to that of
a 1.25V regulator. In a 15V regulator, for example, these
parameters are improved by 15V/1.25V = 12 to 1. This
improvement holds only for those frequencies where the
impedance of the bypass capacitor is less than R1. Ten
microfarads is generally sufficient for 60Hz power line
applications where the ripple frequency is 120Hz since
R1 should be connected directly to the output lead of the
regulator, as close as possible to the specified point 1/8"
from the case. R2 should be connected to the positive
side of the load separately from the positive (ground)
connection to the raw supply. With this arrangement, load
regulation is degraded only by the resistance between the
regulator output pin and the load. If R1 is connected to
the load, regulation will be degraded.
LEAD RESISTANCE HERE DOES
NOT AFFECT LOAD REGULATION
X = 130Ω. The capacitor should have a voltage rating at
C
least as high as the output voltage of the regulator. Values
larger than 10μF may be used, but if the output is larger
than25V, adiode, D2, shouldbeaddedbetweentheoutput
and adjustment pins (see Figure 2).
R2
LOAD
R1
ADJ
+
–V
V
IN
LT137A V
OUT
R2
IN
137A F03
C1
+
+
C3
C2
CONNECT R1
DIRECTLY TO
REGULATOR PIN MINIMIZE THE LENGTH OF
THIS LEAD.
LEAD RESISTANCE HERE
DEGRADES LOAD REGULATION.
R1
D2**
1N4002
ADJ
–V
V
IN
LT137A
V
OUT
–V
OUT
IN
Figure 3
137A F02
D1*
1N4002
*D1 PROTECTS THE REGULATOR FROM INPUT SHORTS TO GROUND. IT IS
REQUIRED ONLY WHEN C3 IS LARGER THAN 20μF AND V IS LARGER THAN 6V.
OUT
**D2 PROTECTS THE ADJUST PIN OF THE REGULATOR FROM OUTPUT SHORTS
IF C2 IS LARGER THAN 10μF AND V IS LARGER THAN –25V.
OUT
Figure 2
137afb
8
LT137A/LM137
LT337A/LM337
TYPICAL APPLICATIONS
High Stability Regulator
A high stability regulator is illustrated in the application
circuitshowntotheright. Theoutputstability, loadregula-
tion, line regulation, thermal regulation, temperature drift,
long term drift, and noise can be improved by a factor of
6.6overthestandardregulatorconfiguration.Thisassumes
a zener whose drift and noise is considerably better than
the regulator itself. The LM329B has 20ppm/°C maximum
drift and about 10 times lower noise than the regulator.
7V
LM329B
R2*
+
1μF
SOLID
TANTALUM
R3
1.5k
1%
R1
1k
1%
ADJ
–V
V
LT137A
V
–V
OUT
OUT
IN
IN
|
V
|
OUT
*R2 =
– 908Ω
–3
137A TA03
In the application shown below, regulators #2 to “N” will
track regulator #1 to within 24mV initially, and to 60mV
over all load, line, and temperature conditions. If any
regulatoroutputisshortedtoground,allotheroutputswill
drop to approximately ≈ –2V. Load regulation of regula-
9.08 • 10
Dual Tracking Supply 1.25V to 20V
tors 2 to “N” will be improved by V /1.25V compared
OUT
+V
V
LT317A
ADJ
V
OUT
+V
OUT
IN
IN
to a standard regulator, so regulator #1 should be the one
R1**
100Ω
1%
which has the lowest load current.
+
+
D1
1N4002
2.2μF*
Multiple Tracking Regulators
+
R2
5k
10μF
10μF
R3
5k
1%
+
C3
R2
10μF
+
R4
5k
1%
C1
+
2μF
1μF
R1
120Ω
SOLID
TANTALUM
D2
1N4002
1N4002
ADJ
2.2μF*
R5**
100Ω
1%
V
REG #1
V
–V
OUT1
OUT
IN
–V
IN
ADJ
LT137A
137A TA02
–V
V
IN
LT337A
V
OUT
–V
OUT
IN
+
+
+
137A TA04
1μF
2μF
SOLID
*SOLID TANTALUM
**R1 OR R5 MAY BE TRIMMED SLIGHTLY TO IMPROVE TRACKING
TANTALUM
1N4002
ADJ
V
REG #2
V
–V
OUT2
OUT
IN
Current Regulator
LT137A
137A TA02
+
C1
+
1μF
SOLID
TANTALUM
1μF
2μF
SOLID TANTALUM
ADJ
ADJ
(–)
V
IN
LT337A
V
(+)
1.25V
OUT
R
S
I
V
REG #N
V
–V
OUT3
OUT
IN
137A TA05
I = 65μA +
LT137A
R
S
137A TA02
(0.8Ω < R < 250Ω)
S
137afb
9
LT137A/LM137
LT337A/LM337
SCHEMATIC DIAGRAM
ADJ
2k
Q1
Q3
Q2
2k
D4
20k
Q4
15pF
Q5
V
OUT
800Ω
D1
D2
D3
Q32 Q34
60k
Q7
Q6
15pF
25pF
5k
600Ω
220Ω
750Ω
100k
18k
2k
Q11
Q33
Q12
Q10
Q8
Q9
100k
D5
20Ω
20Ω
Q13
Q25
Q26
4k
6.8k
12k
250Ω
12k
Q23
480Ω
2pF
5pF
15k
Q22
Q21
12k
Q18
Q20
Q24
Q30
Q19
150Ω
10Ω
1k
Q14
Q27
Q28
Q31
1k
100Ω
270Ω
0.02Ω
2k
Q16
Q17
8k
4k
20k
Q29
2.4k
6k
1k
100Ω
Q15
600Ω
4.2k
500Ω
V
IN
137A SD
137afb
10
LT137A/LM137
LT337A/LM337
PACKAGE DESCRIPTION
OBSOLETE PACKAGES
H Package
3-Lead TO-39 Metal Can
(Reference LTC DWG # 05-08-1330)
.350 – .370
(8.890 – 9.398)
.305 – .335
(7.747 – 8.509)
.050
(1.270)
MAX
.165 – .185
(4.191 – 4.699)
REFERENCE
PLANE
*
.016 – .019**
.500
(12.700)
MIN
(0.406 – 0.483)
DIA
.200
(5.080)
TYP
.100
(2.540)
PIN 1
.029 – .045
(0.737 – 1.143)
.100
(2.540)
.028 – .034
(0.711 – 0.864)
45o
H3(TO-39) 0801
*LEAD DIAMETER IS UNCONTROLLED BETWEEN THE REFERENCE PLANE
AND .050" BELOW THE REFERENCE PLANE
.016 – .024
**FOR SOLDER DIP LEAD FINISH, LEAD DIAMETER IS
(0.406 – 0.610)
K Package
2-Lead TO-3 Metal Can
(Reference LTC DWG # 05-08-1310)
.760 – .775
(19.30 – 19.69)
.320 – .350
(8.13 – 8.89)
.060 – .135
(1.524 – 3.429)
.420 – .480
(10.67 – 12.19)
.038 – .043
(0.965 – 1.09)
1.177 – 1.197
(29.90 – 30.40)
.655 – .675
(16.64 – 17.15)
.210 – .220
(5.33 – 5.59)
.151 – .161
(3.86 – 4.09)
DIA, 2PLCS
.167 – .177
(4.24 – 4.49)
R
.425 – .435
(10.80 – 11.05)
.067 – .077
(1.70 – 1.96)
.490 – .510
(12.45 – 12.95)
R
K2 (TO-3) 0801
137afb
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 representa-
tion that the interconnection of its circuits as described herein will not infringe on existing patent rights.
11
LT137A/LM137
LT337A/LM337
PACKAGE DESCRIPTION
M Package
3-Lead Plastic DD Pak
(Reference LTC DWG # 05-08-1460)
.060
(1.524)
TYP
.390 – .415
(9.906 – 10.541)
.165 – .180
.045 – .055
(4.191 – 4.572)
(1.143 – 1.397)
15° TYP
.330 – .370
(8.382 – 9.398)
.218 – .252
(5.537 – 6.401)
.520 – .570
(13.208 – 14.478)
.013 – .023
(0.330 – 0.584)
.090 – .110
(2.286 – 2.794)
.050
(1.270)
TYP
.095 – .115
(2.413 – 2.921)
.028 – .038
(0.711 – 0.965)
.420
.276
.080
.420
.350
.325
.565
.205
.320
.565
.090
.070 TYP
.090
.100 BSC
.070 TYP
.100 BSC
RECOMMENDED SOLDER PAD LAYOUT
RECOMMENDED SOLDER PAD LAYOUT
FOR THICKER SOLDER PASTE APPLICATIONS
NOTE:
1. DIMENSIONS IN INCH/(MILLIMETER)
2. DRAWING NOT TO SCALE
M(DD3) (STRAIGHT) 0801
T Package
3-Lead Plastic TO-220
(Reference LTC DWG # 05-08-1420)
.147 – .155
(3.734 – 3.937)
DIA
.165 – .180
(4.191 – 4.572)
.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)
.980 – 1.070
(24.892 – 27.178)
.520 – .570
(13.208 – 14.478)
.218 – .252
(5.537 – 6.401)
.013 – .023
(0.330 – 0.584)
.100
(2.540)
BSC
.095 – .115
(2.413 – 2.921)
T3 (TO-220) 0801
.050
(1.270)
TYP
.028 – .038
(0.711 – 0.965)
137afb
LT 0807 REV B • PRINTED IN USA
LinearTechnology Corporation
1630 McCarthy Blvd., Milpitas, CA 95035-7417
12
●
●
© LINEAR TECHNOLOGY CORPORATION 1983
(408) 432-1900 FAX: (408) 434-0507 www.linear.com
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