LT1584/LT1585/LT1587
7A, 4.6A, 3A Low Dropout
Fast Response
Positive Regulators
Adjustable and Fixed
DESCRIPTIO
FEATURES
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Fast Transient Response The LT 1584/LT1585/LT1587 are low dropout three-
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Guaranteed Dropout Voltage at Multiple Currents terminal regulators with 7A, 4.6A and 3A output current
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Load Regulation: 0.05% Typical capability, respectively. Design has been optimized for low
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Trimmed Current Limit voltage applications where transient response and mini-
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On-Chip Thermal Limiting mum input voltage are critical. Similar to the LT1083/4/5
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Standard 3-Pin Power Package family, it has lower dropout voltage and faster transient
response. These improvements make it ideal for low volt-
U
age microprocessor applications requiring a regulated
APPLICATIO S
2.5V to 3.6V output with an input supply below 7V.
TM
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Pentium Processor Supplies
TM
Current limit is trimmed to ensure specified output current
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PowerPC Supplies
and controlled short-circuit current. On-chip thermal lim-
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Other 2.5V to 3.6V Microprocessor Supplies
iting provides protection against any combination of over-
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Low Voltage Logic Supplies
load that would create excessive junction temperatures.
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Battery-Powered Circuitry
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Post Regulator for Switching Supply
The LT1585/LT1587 are available in both the through-hole
and surface mount versions of the industry standard 3-pin
LT1585/7CM, LT1584/5/7CT Adjustable
TO-220 power package. The LT1584 is available in the
LT1585/7CM-3.3, LT1584/5/7CT-3.3 3.3V Fixed
through-hole 3-pin TO-220 power package.
LT1585CM-3.38, LT1584/5CT-3.38 3.38V Fixed
, LTC and LT are registered trademarks of Linear Technology Corporation.
LT1585/7CM-3.45, LT1584/5/7CT-3.45 3.45V Fixed
Pentium is a trademark of Intel Corporation. PowerPC is a trademark of IBM Corporation.
LT1585/7CM-3.6, LT1584/5/7CT-3.6 3.6V Fixed
TYPICAL APPLICATIO
Dropout Voltage vs Output Current
1.5
3.3V, 7A, 4.6A, 3A Regulator 1.4
1.3
LT1584-3.3
1.2
3.3V
LT1585-3.3
V 4.75V
IN
7A, 4.6A, 3A
LT1587-3.3
1.1
+ +
C1
C2*
1.0
10m F
SOLID
TANTALUM
0.9
0.8
* REQUIRED FOR STABILITY
LT1584: C2 = 22m F,
0.7
1585 TA01
LT1585/LT1587: C2 = 10m F
0.6
NOTE: MICROPROCESSOR APPLICATIONS WITH LOAD TRANSIENTS OF 3.8A REQUIRE
0.5
OUTPUT DECOUPLING CAPACITANCE > 1300F ON FIXED VOLTAGE PARTS TO ACHIEVE
0 I
< 50mV OF DEVIATION FROM NOMINAL OUTPUT. CONSULT FACTORY FOR DETAILS FULL LOAD
OUTPUT CURRENT (A)
1585 TA02
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INPUT/OUTPUT DIFFERENTIAL (V)
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ULT1584/LT1585/LT1587
ABSOLUTE AXI U RATI GS
(Note 1)
V ............................................................................. 7V Storage Temperature Range ................. 65C to 150C
IN
Operating Junction Temperature Range Lead Temperature (Soldering, 10 sec).................. 300C
C-Grade
PRECONDITIONI G
Control Section ................................... 0C to 125C
Power Transistor ................................. 0C to 150C 100% Thermal Limit Functional Test
I-Grade
Control Section ............................... 40C to 125C
Power Transistor ............................. 40C to 150C
PACKAGE/ORDER INFORMATION
ORDER PART
ORDER PART
NUMBER NUMBER
FRONT VIEW FRONT VIEW
LT1585CM LT1584CT
3 V
IN
3 V LT1587CM LT1585CT
IN
TAB TAB
LT1587CT
2 V
IS IS 2 V
OUT OUT
OUTPUT OUTPUT
1 ADJ
1
ADJ
M PACKAGE T PACKAGE
3-LEAD PLASTIC DD 3-LEAD PLASTIC TO-220
= 30C/W* = 50C/W
JA JA
LT1585CM-3.3 LT1584CT-3.3
LT1585CM-3.38 LT1584IT-3.3
FRONT VIEW LT1585CM-3.45 LT1585CT-3.3
FRONT VIEW
LT1585CM-3.6 LT1587CT-3.3
3 V
IN
3 V
IN
LT1587CM-3.3 LT1584CT-3.38
TAB
TAB
LT1587CM-3.45 LT1585CT-3.38
IS 2 V
OUT IS 2 V
OUT
OUTPUT
OUTPUT
LT1587CM-3.6 LT1584CT-3.45
1 GND
LT1585CT-3.45
1 GND
LT1587CT-3.45
M PACKAGE T PACKAGE
LT1584CT-3.6
3-LEAD PLASTIC DD 3-LEAD PLASTIC TO-220
= 30C/W* LT1585CT-3.6
JA = 50C/W
JA
LT1587CT-3.6
* With package soldered to 0.5 square inch copper area over backside Consult LTC Marketing for parts specified with wider operating temperature ranges.
ground plane or internal power plane. can vary from 20C/W to
JA
>40C/W with other mounting techniques.
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