LP3875-ADJ
1.5A Fast Ultra Low Dropout Linear Regulators
General Description
The LP3875-ADJ fast ultra low-dropout linear regulators op-
erate from a +2.5V to +7.0V input supply. These ultra low
dropout linear regulators respond very quickly to step
changes in load, which makes them suitable for low voltage
microprocessor applications. The LP3875-ADJ is developed
on a CMOS process which allows low quiescent current
operation independent of output load current. This CMOS
process also allows the LP3875-ADJ to operate under ex-
tremely low dropout conditions.
Dropout Voltage: Ultra low dropout voltage; typically 38mV
at 150mA load current and 380mV at 1.5A load current.
Ground Pin Current: Typically 6mA at 1.5A load current.
Shutdown Mode: Typically 10nA quiescent current when
the shutdown pin is pulled low.
Adjustable Output Voltage: The output voltage may be
programmed via two external resistors.
Features
n
Ultra low dropout voltage
n
Low ground pin current
n
Load regulation of 0.06%
n
10nA quiescent current in shutdown mode
n
Guaranteed output current of 1.5A DC
n
Available in TO-263, TO-220 and SOT-223 packages
n
Minimum output capacitor requirements
n
Overtemperature/overcurrent protection
n
-40C to +125C junction temperature range
Applications
n
Microprocessor power supplies
n
GTL, GTL+, BTL, and SSTL bus terminators
n
Power supplies for DSPs
n
SCSI terminator
n
Post regulators
n
High efficiency linear regulators
n
Battery chargers
n
Other battery powered applications
Typical Application Circuit
20074645
*See Application Hints
July 2005
LP3875-ADJ
1.5A
Fast
Ultra
Low
Dropout
Linear
Regulators
2005 National Semiconductor Corporation
DS200746
www.national.com
Ordering Information
20074631
Package Type Designator is "T" for TO220 package, "S" for TO263 package, and "MP" for SOT-223 package.
TABLE 1. Package Marking and Ordering Information
Output
Voltage
Order Number
Description
(Current,
Option)
Package Type
Package Marking
Supplied As:
ADJ
LP3875EMP-ADJ
1.5A, Adj
SOT223-5
LHSB
1000 Units on Tape
and Reel
ADJ
LP3875EMPX-ADJ
1.5A, Adj
SOT223-5
LHSB
2000 Units on Tape
and Reel
ADJ
LP3875ES-ADJ
1.5A, Adj
TO263-5
LP3875ES-ADJ
Rail
ADJ
LP3875ESX-ADJ
1.5A, Adj
TO263-5
LP3875ES-ADJ
Tape and Reel
ADJ
LP3875ET-ADJ
1.5A, Adj
TO220-5
LP3875ET-ADJ
Rail
LP3875-ADJ
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3
Absolute Maximum Ratings
(Note 1)
If Military/Aerospace specified devices are required,
please contact the National Semiconductor Sales Office/
Distributors for availability and specifications.
Storage Temperature Range
-65C to +150C
Lead Temperature
(Soldering, 5 sec.)
260C
ESD Rating (Note 3)
2 kV
Power Dissipation (Note 2)
Internally Limited
Input Supply Voltage (Survival)
-0.3V to +7.5V
Shutdown Input Voltage
(Survival)
-0.3V to +7.5V
Output Voltage (Survival), (Note
6), (Note 7)
-0.3V to +6.0V
I
OUT
(Survival)
Short Circuit Protected
Operating Ratings
Input Supply Voltage (Operating),
(Note 10)
2.5V to 7.0V
Shutdown Input Voltage
(Operating)
-0.3V to 7.0V
Maximum Operating Current (DC)
1.5A
Operating Junction Temp. Range
-40C to +125C
Electrical Characteristics
LP3875-ADJ
Limits in standard typeface are for T
J
= 25C, and limits in boldface type apply over the full operating temperature range.
Unless otherwise specified: V
IN
= V
O(NOM)
+ 1V, I
L
= 10 mA, C
OUT
= 10F, V
SD
= 2V.
Symbol
Parameter
Conditions
Typ
(Note 4)
LP3875-ADJ
(Note 5)
Units
Min
Max
V
ADJ
Adjust Pin Voltage
V
OUT
+1V
V
IN
7V
10 mA
I
L
1.5A
1.216
1.198
1.180
1.234
1.253
V
I
ADJ
Adjust Pin Input Current
V
OUT
+1V
V
IN
7V
10 mA
I
L
1.5A
10
100
nA
V
OL
Output Voltage Line
Regulation (Note 8)
V
OUT
+1V
V
IN
7.0V
0.02
0.06
%
V
O
/
I
OUT
Output Voltage Load
Regulation
(Note 8)
10 mA
I
L
1.5A
0.06
0.12
%
V
IN
- V
OUT
Dropout Voltage
(Note 9)
I
L
= 150 mA
38
50
60
mV
I
L
= 1.5A
380
450
550
I
GND
Ground Pin Current In
Normal Operation Mode
I
L
= 150 mA
5
9
10
mA
I
L
= 1.5A
6
14
15
I
GND
Ground Pin Current In
Shutdown Mode
V
SD
0.3V
0.01
10
A
-40C
T
J
85C
50
I
O(PK)
Peak Output Current
V
O
V
O(NOM)
- 4%
1.8
A
Short Circuit Protection
I
SC
Short Circuit Current
3.2
A
LP3875-ADJ
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