LT1584/LT1585/LT1587
7A, 4.6A, 3A Low Dropout
Fast Response
Positive Regulators
Adjustable and Fixed
FEATURES
s
s
s
s
s
s
DESCRIPTION
The LT
®
1584/LT1585/LT1587 are low dropout three-
terminal regulators with 7A, 4.6A and 3A output current
capability, respectively. Design has been optimized for low
voltage applications where transient response and mini-
mum input voltage are critical. Similar to the LT1083/4/5
family, it has lower dropout voltage and faster transient
response. These improvements make it ideal for low volt-
age microprocessor applications requiring a regulated
2.5V to 3.6V output with an input supply below 7V.
Current limit is trimmed to ensure specified output current
and controlled short-circuit current. On-chip thermal lim-
iting provides protection against any combination of over-
load that would create excessive junction temperatures.
The LT1585/LT1587 are available in both the through-hole
and surface mount versions of the industry standard 3-pin
TO-220 power package. The LT1584 is available in the
through-hole 3-pin TO-220 power package.
, LTC and LT are registered trademarks of Linear Technology Corporation.
Pentium is a trademark of Intel Corporation. PowerPC is a trademark of IBM Corporation.
Fast Transient Response
Guaranteed Dropout Voltage at Multiple Currents
Load Regulation: 0.05% Typ
Trimmed Current Limit
On-Chip Thermal Limiting
Standard 3-Pin Power Package
APPLICATIONS
s
s
s
s
s
s
Pentium
TM
Processor Supplies
PowerPC
TM
Supplies
Other 2.5V to 3.6V Microprocessor Supplies
Low Voltage Logic Supplies
Battery-Powered Circuitry
Post Regulator for Switching Supply
Adjustable
3.3V Fixed
3.38V Fixed
3.45V Fixed
3.6V Fixed
LT1585/7CM, LT1584/5/7CT
LT1585/7CM-3.3, LT1584/5/7CT-3.3
LT1585CM-3.38, LT1584/5CT-3.38
LT1585/7CM-3.45, LT1584/5/7CT-3.45
LT1585/7CM-3.6, LT1584/5/7CT-3.6
TYPICAL APPLICATION
1.5
Dropout Voltage vs Output Current
1.4
3.3V, 7A, 4.6A, 3A Regulator
INPUT/OUTPUT DIFFERENTIAL (V)
V
IN
≥
4.75V
LT1584-3.3
LT1585-3.3
LT1587-3.3
C1
10µF
3.3V
7A, 4.6A, 3A
C2*
SOLID
TANTALUM
1.3
1.2
1.1
1.0
0.9
0.8
0.7
0.6
0.5
0
OUTPUT CURRENT (A)
1585 TA02
+
+
* REQUIRED FOR STABILITY
LT1584: C2 = 22µF,
LT1585/LT1587: C2 = 10µF
1585 TA01
NOTE: MICROPROCESSOR APPLICATIONS WITH LOAD TRANSIENTS OF 3.8A REQUIRE
OUTPUT DECOUPLING CAPACITANCE > 1300µF ON FIXED VOLTAGE PARTS TO ACHIEVE
< 50mV OF DEVIATION FROM NOMINAL OUTPUT. CONSULT FACTORY FOR DETAILS
U
U
U
I
FULL LOAD
1
LINER [ LINEAR TECHNOLOGY ]
