LMS1585A/LMS1587
5A and 3A Low Dropout Fast Response Regulators
General Description
The LMS1585Aand LMS1587 are low dropout positive regu-
lators with output load current of 5A and 3A respectively.
Their low dropout voltage (1.2V) and fast transient response
make them an excellent solution for low voltage micropro-
cessor applications.
The LMS1585A/87 are available in adjustable versions,
which can set the output voltage with only two external resis-
tors. In addition, they are also available in a 3.3V fixed volt-
age version (Note 9).
The LMS1585A/87 circuits include a zener trimmed bandgap
reference, current limiting and thermal shutdown.
The LMS1585A/87 series are available in TO-220 and TO-
263 packages.
Features
nFast transient response
nAvailable in Adjustable, 1.5V, and 3.3V versions
nCurrent limiting and thermal protection
nCommercial temp. range 0˚C to 125˚C
nIndustrial temp. range −40˚C to 125˚C
nLine regulation 0.005% (typical)
nLoad regulation 0.05% (typical)
nDirect replacement for LT™1585A/87
Applications
nPentium™processor supplies
nPowerPC™supplies
nOther 2.5V to 3.6V microprocessor supplies
nLow voltage logic supplies
Typical Application
Connection Diagrams
LT is a registered trademark of Linear Technology Corporation
Pentium is a registered trademark of Intel Corporation
PowerPC is a registred trademark of IBM
DS101197-1
TO-220
DS101197-36
Top View
TO-263
DS101197-35
Top View
April 2000
LMS1585A/LMS1587 5A Low Dropout Fast Response Regulators
© 2000 National Semiconductor Corporation DS101197 www.national.com
Ordering Information
Output
Current Package Temperature Range Part Number Transport Media NSC
Drawing
3A TO-263 0˚C to 125˚C LMS1587CS-ADJ Rails
TS3B
LMS1587CSX-ADJ Tape and Reel
LMS1587CS-1.5 Rails
LMS1587CSX-1.5 Tape and Reel
LMS1587CS-3.3 Rails
LMS1587CSX-3.3 Tape and Reel
−40˚C to 125˚C LMS1587IS-ADJ Rails
LMS1587ISX-ADJ Tape and Reel
LMS1587IS-3.3 Rails
LMS1587ISX-3.3 Tape and Reel
TO-220 0˚C to 125˚C LMS1587CT-ADJ Rails
T03B
LMS1587CT-3.3 Rails
−40˚C to 125˚C LMS1587IT-ADJ Rails
LMS1587IT-3.3 Rails
5A TO-263 0˚C to 125˚C LMS1585ACS-ADJ Rails
TS3B
LMS1585ACSX-ADJ Tape and Reel
LMS1585ACS-3.3 Rails
LMS1585ACSX-3.3 Tape and Reel
−40˚C to 125˚C LMS1585AIS-ADJ Rails
LMS1585AISX-ADJ Tape and Reel
LMS1585AIS-3.3 Rails
LMS1585AISX-3.3 Tape and Reel
TO-220 0˚C to 125˚C LMS1585ACT-ADJ Rails
T03B
LMS1585ACT-3.3 Rails
−40˚C to 125˚C LMS1585AIT-ADJ Rails
LMS1585AIT-3.3 Rails
LMS1585A/LMS1587
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Simplified Schematic
DS101197-14
LMS1585A/LMS1587
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Absolute Maximum Ratings (Note 1)
If Military/Aerospace specified devices are required,
please contact the National Semiconductor Sales Office/
Distributors for availability and specifications.
Maximum Input to Output Voltage
(V
IN
to GND) 13V
Power Dissipation (Note 2) Internally Limited
Junction Temperature (T
J
)(Note 2) 150˚C
Storage Temperature Range -65˚C to 150˚C
Lead Temperature 260˚C, 10 sec
ESD Tolerance (Note 3) 2000V
Electrical Characteristics
Typicals and limits appearing in normal type apply for T
J
= 25˚C. Limits appearing in Boldface type apply over the entire junc-
tion temperature range for operation, 0˚C to 125˚C for commercial grade and −40˚C to 125˚C for industrial grade.
Symbol Parameter Conditions Min
(Note
5)
Typ
(Note
4)
Max
(Note
5) Units
V
REF
Reference Voltage LMS1585A-ADJ
V
IN
−V
OUT
= 3V, I
OUT
= 10mA
10mA ≤I
OUT
≤5A, 1.5V ≤V
IN
−V
OUT
≤5.75V 1.238
1.225 1.25
1.250 1.262
1.275 V
V
LMS1587-ADJ
10mA ≤I
OUT
≤3A, 1.5V ≤V
IN
−V
OUT
≤5.75V 1.225 1.250 1.275 V
V
OUT
Output Voltage LMS1585A-3.3
I
OUT
= 0mA, V
IN
=5V
0≤I
OUT
≤5A, 4.75V ≤V
IN
≤7V 3.267
3.235 3.300
3.300 3.333
3.365 V
V
LMS1587-1.5
V
IN
= 5V, I
OUT
= 0mA, T
J
= 25˚C
0≤I
OUT
≤3A, 3V ≤V
IN
≤7V 1.485
1.470 1.500
1.500 1.515
1.530 V
V
LMS1587-3.3
0≤I
OUT
≤3A, 4.75V ≤V
IN
≤7V 3.235 3.300 3.365 V
∆V
OUT
Line Regulation
(Note 6) LMS1585A/87-ADJ
I
OUT
= 10mA, 2.75V ≤V
IN
≤7V 0.005 0.2 %
LMS1585A/87-3.3
I
OUT
= 0mA, 4.75V ≤V
IN
≤7V 0.005 0.2 %
LMS1587-1.5
I
OUT
= 0mA, 3V ≤V
IN
≤7V 0.005 0.2 %
∆V
OUT
Load Regulation
(Note 6) LMS1585A-ADJ
V
IN
−V
OUT
= 3V, 10mA ≤I
OUT
≤5A 0.05
0.05 0.3
0.5 %
LMS1585A-3.3
V
IN
= 5V, 0 ≤I
OUT
≤5A 0.05
0.05 0.3
0.5 %
LMS1587-ADJ
V
IN
−V
OUT
= 3V, 10mA ≤I
OUT
≤3A 0.05
0.05 0.3
0.5 %
LMS1587-1.5
V
IN
= 5V, 0 ≤I
OUT
≤3A 0.05
0.05 0.3
0.5 %
%
LMS1587-3.3
V
IN
= 5V, 0 ≤I
OUT
≤3A 0.05
0.05 0.3
0.5 %
V
IN
−V
OUT
Dropout Voltage LMS1585A-ADJ/LMS1587-ADJ
∆V
REF
= 1%, I
OUT
= 3A 1.15 1.3 V
LMS1585A-3.3/LMS1587-3.3/LMS1587-1.5
∆V
OUT
= 1%, I
OUT
= 3A 1.15 1.3 V
LMS1585A-ADJ
∆V
REF
= 1%, I
OUT
= 5A 1.2 1.4 V
LMS1585A-3.3
∆V
OUT
= 1%, I
OUT
= 5A 1.2 1.4 V
I
LIMIT
Current Limit LMS1585A-ADJ/LMS1585A-3.3
V
IN
−V
OUT
= 5.5V 5.0 6.6 A
LMS1587-ADJ/LMS1587-3.3
V
IN
−V
OUT
= 5.5V 3.1 4.3 A
LMS1587-1.5
V
IN
−V
OUT
= 5.5V 3.100 3.750 A
LMS1585A/LMS1587
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Electrical Characteristics (Continued)
Typicals and limits appearing in normal type apply for T
J
= 25˚C. Limits appearing in Boldface type apply over the entire junc-
tion temperature range for operation, 0˚C to 125˚C for commercial grade and −40˚C to 125˚C for industrial grade.
Symbol Parameter Conditions Min
(Note
5)
Typ
(Note
4)
Max
(Note
5) Units
Minimum Load
Current (Note 7) LMS1585A/87-ADJ
1.5V ≤V
IN
−V
OUT
≤5.75V 2.0 10.0 mA
Quiescent Current LMS1585A-3.3/LMS1587-3.3/LMS1587-1.5
V
IN
= 5V 7.0 13.0 mA
Thermal Regulation T
A
= 25˚C, 30ms Pulse 0.003 %/W
Ripple Rejection LMS1585A-ADJ
f
RIPPLE
= 120Hz, V
IN
−V
OUT
= 3V, I
OUT
=5A
C
OUT
= 25µF Tantalum 72 dB
LMS1585-3.3
f
RIPPLE
= 120Hz, C
OUT
= 25µF Tantalum,
I
OUT
= 5A, V
IN
= 6.3V 72 dB
LMS1587-ADJ
f
RIPPLE
= 120Hz, V
IN
−V
OUT
= 3V, I
OUT
=3A
C
OUT
= 25µF Tantalum 72 dB
LMS1587-1.5
f
RIPPLE
= 120Hz, C
OUT
= 25µF Tantalum,
I
OUT
= 3A, V
IN
= 4.5V 60 72 dB
LMS1587-3.3
f
RIPPLE
= 120Hz, C
OUT
= 25µF Tantalum,
I
OUT
= 3A, V
IN
= 6.3V 72 dB
Adjust Pin Current 55 120 µA
Adjust Pin Current 10mA ≤I
OUT
≤I
FULLLOAD
,
1.5V ≤V
IN
−V
OUT
≤5.75V (Note 8) 0.2 µA
Temperature Stability 0.5 %
Long Term Stability T
A
= 125˚C, 1000Hrs 0.03 %
RMS Output Noise
(% of V
OUT
)10Hz ≤f≤10kHz 0.003 %
Thermal Resistance
Junction-to-Case 3-Lead TO-263: Control/Output Section
3-Lead TO-220: Control/Output Section 0.65/2.7
0.65/2.7 ˚C/W
˚C/W
Note 1: Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for which the device is in-
tended to be functional, but specific performance is not guaranteed. For guaranteed specifications and the test conditions, see the Electrical Characteristics.
Note 2: The maximum power dissipation is a function of TJ(max) ,θJA, and TA. The maximum allowable power dissipation at any ambient temperature
is PD=(T
J(max)–T A)/θJA. All numbers apply for packages soldered directly into a PC board.
Note 3: For testing purposes, ESD was applied using human body model, 1.5kΩin series with 100pF.
Note 4: Typical Values represent the most likely parametric norm.
Note 5: All limits are guaranteed by testing or statistical analysis.
Note 6: Load and line regulation are measured at constant junction temperature, and are guaranteed up to the maximum power dissipation of 30W. Power dissipa-
tion is determined by the input/output differential and the output current. Guaranteed maximum power dissipation will not be available over the full input/output range.
Note 7: The minimum output current required to maintain regulation.
Note 8: IFULLLOAD is 5A for LMS1585A and 3A for LMS1587.
Note 9: Consult factory for other fixed voltage options.
LMS1585A/LMS1587
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Physical Dimensions inches (millimeters) unless otherwise noted
3-Lead TO-263 Package
NSC Package Number TS3B
LMS1585A/LMS1587
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Physical Dimensions inches (millimeters) unless otherwise noted (Continued)
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DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT AND GENERAL
COUNSEL OF NATIONAL SEMICONDUCTOR CORPORATION. As used herein:
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systems which, (a) are intended for surgical implant
into the body, or (b) support or sustain life, and
whose failure to perform when properly used in
accordance with instructions for use provided in the
labeling, can be reasonably expected to result in a
significant injury to the user.
2. A critical component is any component of a life
support device or system whose failure to perform
can be reasonably expected to cause the failure of
the life support device or system, or to affect its
safety or effectiveness.
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www.national.com
3-Lead TO-220 Package
NSC Package Number T03B
LMS1585A/LMS1587 5A Low Dropout Fast Response Regulators
National does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and National reserves the right at any time without notice to change said circuitry and specifications.
