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Supertex inc.
High Input Voltage, Adjustable
*
3-Terminal Linear Regulator
LR12
Features
► 13.2 to 100V input voltage range
► Stable with 100nF output capacitor
► Adjustable 1.20 to 88V output regulation
► 5% reference voltage tolerance
► Output current limiting, 50mA min.
► 10µA typical ADJ current
► Over temperature protection
► Available in 3 different packages
Applications
► DC/DC SMPS startup circuits
► Adjustable high voltage constant current sources
► Industrial controls
► Motor controls
► Battery powered systems
► Power supplies
► Telecom applications
► LED drivers
► Automotive applications
General Description
The Supertex LR12 is a high voltage, low output current,
adjustable linear regulator. It has a wide operating input voltage
range of 13.2 - 100V. The output voltage can be adjusted from
1.20 - 88V, provided that the input voltage is at least 12V greater
than the output voltage. The output voltage can be adjusted
by means of two external resistors R1 and R2 as shown in the
typical application circuits. The LR12 regulates the voltage
difference between VOUT and ADJ pins to a nominal value of
1.20V. The 1.20V is amplied by the external resistor ratio R1
and R2. An internal constant bias current of typically 10µA is
connected to the ADJ pin. This increases V
voltage of 10µA times R2.
The LR12 has current limiting and temperature limiting. The
output current limit is 100mA maximum and the minimum
temperature limit is 125°C. An output short circuit current will
therefore be limited to 100mA maximum. When the junction
temperature reaches its temperature limit, the output current
and/or output voltage will decrease to keep the junction
temperature from exceeding its temperature limit. For SMPS
start-up circuit applications, the LR12 turns off when an external
voltage greater than the output voltage of the LR12 is applied
to VOUT of the LR12. To maintain stability, a bypass capacitor
of 100nF or larger and a minimum DC output current of 500µA
are required.
by a constant
OUT
LR12 Typical Application
V
IN
13.2 to 100V
C
Doc.# DSFP-LR12
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VIN
VOUT
ADJ
1
* Required for conditions where V
LR12
R
2
V
OUT
1.2 to 88V
R
1
C
2
is less than V
IN
OUT
.
R
LOAD
Supertex inc.
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Page 2
LR12
Ordering Information
Part Number Package Options Packing
LR12K4-G TO-252 (D-PAK) 2000/Reel
LR12LG-G 8-Lead SOIC 2500/Reel
LR12N3-G TO-92 1000/Bag
LR12N3-G P002 TO-92 2000/Reel
LR12N3-G P003 TO-92 2000/Reel
LR12N3-G P005 TO-92 2000/Reel
LR12N3-G P013 TO-92 2000/Reel
LR12N3-G P014 TO-92 2000/Reel
-G denotes a lead (Pb)-free / RoHS compliant package
Absolute Maximum Ratings
Parameter Value
V
IN-ADJ
V
OUT-ADJ
VIN - V
OUT
-0.5V to +120V
-10V to +10V
-0.5V to +120V
Operating ambient temperature -40°C to +85°C
Operating junction temperature -40°C to +125°C
Storage temperature -65°C to +150°C
Power Dissipation
TO-252 (D-PAK)
8-Lead SOIC
TO-92
@ TA = 25OC
2.0W
1.8W
0.6W
Typical Thermal Resistance
Package θ
TO-252 81OC/W
8-Lead SOIC 101OC/W
TO-92 132OC/W
(OC/W)
ja
Pin Conguration
VOUT
ADJ
TO-252 (D-PAK)
ADJ
NC
NC
VIN
8-Lead SOIC
VOUT
VOUT
VOUT
VOUT
ADJ
VIN
TO-92
Product Marking
Si YYWW
LR12K4
LLLLLLL
Package may or may not include the following marks: Si or
YYWW
LR12
LLLL
Package may or may not include the following marks: Si or
SiLR
12
Y WLL
Package may or may not include the following marks: Si or
YY = Year Sealed
WW = Week Sealed
L = Lot Number
= “Green” Packaging
TO-252 (D-PAK)
YY = Year Sealed
WW = Week Sealed
L = Lot Number
= “Green” Packaging
8-Lead SOIC
Y = Last Digit of Year Sealed
W = Code for Week Sealed
L = Lot Number
= “Green” Packaging
TO-92
VOUT
Electrical Characteristics (Test conditions unless otherwise specied: -40
Sym Parameter Min Typ Max Units Conditions
V
IN - VOUT
V
OUT
Input to output voltage difference 12 - 98.8 V ---
Overall output voltage regulation 1.14 1.20 1.26 V 13.2V < VIN <100V, R1 = 2.4KΩ, R2 = 0
O
C < TA < +85OC)
Line regulation - 0.003 0.03 %/V 15V < V
V
0.5mA< I
V
-40OC < TA < 85OC
ΔV
OUT
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Load regulation - 1.4 3.0 %
Temperature regulation -1.0 - +1.0 %
2
= 15V, V
IN
= 15V, V
IN
<100V, V
IN
OUT
<50mA
OUT
OUT
= 5.0V, I
OUT
= 5.0V,
= 5.0V, I
= 10mA,
OUT
Supertex inc.
www.supertex.com
OUT
= 0.5A
Page 3
Electrical Characteristics (cont.)
Sym Parameter Min Typ Max Units Conditions
LR12
I
OUT
Minimum output current 0.5 - - mA Includes R1 and load current
Output current limit
DV
I
ADJ
C2
OUT/DVIN
T
LIMIT
Adjust output current 5.0 10 15 µA ---
Minimum output load
capacitance
Ripple rejection ratio 50 60 - dB 120Hz, V
Junction temperature limit 125 - -
Functional Block Diagram
VIN
Overtemp &
Overcurrent
100 - - nF ---
Pass
Element
50 - 100
ma
- - -0.5 T
O
C ---
6.5V
1.2V
1.0kΩ
TJ < 85OC, V
< 125OC, VIN - V
J
OUT
LR12
10μA
- V
IN
OUT
= 5.0V
VOUT
ADJ
< 12V
OUT
< 100V
Current Limit
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100
90
80
(mA)
C
I
70
60
50
-40 -20 0 20 40 60 80 100
Temperature (OC)
3
Supertex inc.
www.supertex.com
Page 4
Typical Application Circuits
Figure 1: High Input Voltage, 5.0V Output Linear Regulator
* Required for conditions where VIN is less than V
V
=
IN
17 - 100V
C
1
Figure 2: SMPS Start-Up Circuit
V
= 15 to 100V
IN
.
OUT
VIN
LR12
ADJ
*
VOUT
R
2
18.2kΩ
±1%
V
AUX
R
1
6.04kΩ
±1%
V
V
= 5.0V
OUT
C
100nF
= 1.20V + I
OUT
LR12
2
R
2
1+
R
1
R
LOAD
≤ 16.5kΩ
ADJ R2
+
V
1
OUT
-
VIN
VOUT
ADJ
LR12
V
CC
FB
PWM IC
Figure 3: High Voltage Adjustable Constant Current Source
+
V
IN
15 - 100V
-
=
VIN
LR12
ADJ
VOUT
R
100nF
1.20V
I
=
OUT
+
2
V
OUT
-
R
Doc.# DSFP-LR12
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Supertex inc.
4
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Typical Performance Curves
V
= 1.2V
OUT
2.4kΩ
13.2V
VIN
VOUT
ADJ
LR12
100nF
1.30
1.25
1.20
(V)
1.15
OUT
V
1.10
1.05
1.00
-50 -25 0 25 50 75 100 125
Temperature Variation
T
(junction)
(oC)
LR12
25V
VIN
LR12
ADJ
VOUT
18.2kΩ
±1%
V
OUT
= 5.0V
6.04kΩ
±1%
I
OUT
100nF
R
LOAD
5.30
5.25
5.20
5.15
5.10
(V)
5.05
OUT
V
5.00
4.95
4.90
4.85
4.80
0 5 10 15 20 25 30 35 40 45 50
Load Regulation
I
(mA)
OUT
Doc.# DSFP-LR12
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Supertex inc.
5
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Page 6
Typical Performance Curves (cont.)
= 5.0V
V
OUT
6.04kΩ
±1%
100nF
0V to 50V
VIN
LR12
VOUT
ADJ
1.0kΩ
(V)
OUT
V
6.0
5.0
4.0
3.0
V
OUT
vs. V
LR12
IN
20V
P-P
@ 120Hz
65V
VIN
LR12
18.2kΩ±1%
VOUT
ADJ
18.2kΩ ±1%
V
OUT
6.04kΩ
±1%
= 5.0V
I
OUT
100nF
2.0
1.0
0
0 20 40 60 80 100
V
(V)
IN
-65
-64
-63
R
LOAD
-62
Ripple Rejection
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-61
Ripple Rejection Ratio (dB)
-60
0 10 20 30 40 50
I
(mA)
OUT
Supertex inc.
6
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Page 7
Typical Performance Curves (cont)
LR12
Load Transient Response
V
OUT
6.04kΩ
±1%
25V
VIN
LR12
VOUT
ADJ
18.2kΩ
±1%
Load Transient Response, Load = 509Ω Line Turn On/Off Response
= 5.0V
100nF
10kΩ
Line Transient Response
100V
VIN
LR12
SW
509Ω
V
0V
IN
V
IN
0V
ADJ
VOUT
18.2kΩ
±1%
6.04kΩ
±1%
100nF
10kΩ
Doc.# DSFP-LR12
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Line Power Up Transient Line Power Down Transient
Supertex inc.
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Page 8
3-Lead TO-252 (D-PAK) Package Outline (K4)
LR12
E
4
1 2 3
Front View
b3
E1
L3
θ1
D1
D
L4
L5
Note 1
b2
e
Rear View
b
View B
Side View
A
c2
H
L2
Gauge
Plane
θ
L
L1
A1
Seating
Plane
View B
Note:
1. Although 4 terminal locations are shown, only 3 are functional. Lead number 2 was removed.
Symbol A A1 b b2 b3 c2 D D1 E E1 e H L L1 L2 L3 L4 L5
Dimen-
sion
(inches)
JEDEC Registration TO-252, Variation AA, Issue E, June 2004.
* This dimension is not specied in the JEDEC drawing.
Drawings not to scale.
Supertex Doc. #: DSPD-3TO252K4, Version E091009.
MIN .086 .000* .025 .030 .195 .018 .235 .205 .250 .170
NOM - - - - - - .240 - - - - .060 - - - - -
MAX .094 .005 .035 .045 .215 .035 .245 .217* .265 .182* .410 .070 .050 .040 .060 10O15
.090
BSC
.370 .055
.108
REF
.035 .025* .045 0O0
.020
BSC
θ
θ1
O
O
Doc.# DSFP-LR12
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Supertex inc.
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Page 9
8-Lead SOIC (Narrow Body) Package Outline (LG)
4.90x3.90mm body, 1.75mm height (max), 1.27mm pitch
LR12
D
8
Note 1
(Index Area
D/2 x E1/2)
EE1
1
Top View
Note 1
A
h
A2
A
A1
e
Side View
Seating
Plane
b
A
θ1
L
L1
View B
h
View A-A
L2
θ
Gauge
Plane
Seating
Plane
View B
Note:
1. This chamfer feature is optional. A Pin 1 identier must be located in the index area indicated. The Pin 1 identier can be: a molded mark/identier;
an embedded metal marker; or a printed indicator.
Symbol A A1 A2 b D E E1 e h L L1 L2 θ θ1
O
0
Dimension
(mm)
MIN 1.35* 0.10 1.25 0.31 4.80* 5.80* 3.80*
NOM - - - - 4.90 6.00 3.90 - - - -
1.27
BSC
0.25 0.40
1.04
REF
0.25
BSC
MAX 1.75 0.25 1.65* 0.51 5.00* 6.20* 4.00* 0.50 1.27 8O15
JEDEC Registration MS-012, Variation AA, Issue E, Sept. 2005.
* This dimension is not specied in the JEDEC drawing.
Drawings are not to scale.
Supertex Doc. #: DSPD-8SOLGTG, Version I041309.
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Supertex inc.
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O
5
O
Page 10
3-Lead TO-92 Package Outline (N3)
D
Seating
Plane
1 2 3
L
LR12
A
b
e1
e
Front View
E1
1
2
3
Bottom View
Symbol A b c D E E1 e e1 L
MIN .170 .014
Dimensions
(inches)
NOM - - - - - - - - -
MAX .210 .022
JEDEC Registration TO-92.
* This dimension is not specied in the JEDEC drawing.
† This dimension differs from the JEDEC drawing.
Drawings not to scale.
Supertex Doc.#: DSPD-3TO92N3, Version E041009.
†
†
c
Side View
E
†
.014
.022
.175 .125 .080 .095 .045 .500
†
.205 .165 .105 .105 .055 .610*
(The package drawing(s) in this data sheet may not reect the most current specications. For the latest package outline
information go to http://www.supertex.com/packaging.html.)
Supertex inc. does not recommend the use of its products in life support applications, and will not knowingly sell them for use in such applications unless it receives
an adequate “product liability indemnification insurance agreement.” Supertex inc. does not assume responsibility for use of devices described, and limits its liability
to the replacement of the devices determined defective due to workmanship. No responsibility is assumed for possible omissions and inaccuracies. Circuitry and
specifications are subject to change without notice. For the latest product specifications refer to the Supertex inc. (website: http//www.supertex.com)
©2013 Supertex inc. All rights reserved. Unauthorized use or reproduction is prohibited.
Doc.# DSFP-LR12
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Supertex inc.
1235 Bordeaux Drive, Sunnyvale, CA 94089
Tel: 408-222-8888
www.supertex.com
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