LD1085
3 A low drop positive voltage regulator: adjustable and fixed
Datasheet
-
production data
Unlike PNP regulators, where a part of the output
current is wasted as quiescent current, the
LD1085 quiescent current flows into the load,
thus increase efficiency. Only a 10 µF minimum
capacitor is need for stability.
TO-220FP
TO-220
The device is supplied in TO-220, TO-220FP,
D²PAK and D²PAK/A packages. On-chip trimming
allows the regulator to reach a very tight output
voltage tolerance, within ± 1% at 25 °C.
D²PAK
D²PAK/A
Features
•
Typical dropout 1.3 V (at 3 A)
•
Three terminal adjustable or fixed output
voltage 1.8 V, 2.5 V, 3.3 V, 5 V
•
Guaranteed output current up to 3 A
•
Output tolerance ± 1% at 25 °C and ± 2% in full
temperature range
•
Internal power and thermal limit
•
Wide operating temperature range -40 °C to
125 °C
•
Package available: TO-220, TO-220FP,
D²PAK, D²PAK/A
•
Pinout compatibility with standard adjustable
VREG
Description
The LD1085 is a low drop voltage regulator able
to provide up to 3 A of output current. Dropout is
guaranteed at a maximum of 1.2 V at the
maximum output current, decreasing at lower
loads. The LD1085 is pin-to-pin compatible with
the older 3-terminal adjustable regulators, but
offers better performance in terms of drop and
output tolerance.
October 2013
This is information on a product in full production.
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Contents
LD1085
Contents
1
2
3
4
5
6
7
8
9
10
Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Pin configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Maximum ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Application schematic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Electrical characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Typical characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Package mechanical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Packaging mechanical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Order codes
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
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LD1085
Maximum ratings
3
Maximum ratings
Table 1. Absolute maximum ratings
Symbol
V
I
I
O
P
D
T
STG
T
OP
DC input voltage
Output current
Power dissipation
Storage temperature range
Operating junction temperature range
Parameter
Value
30
Internally limited
Internally limited
-55 to +150
-40 to +125
Unit
V
mA
mW
°C
°C
Note:
Absolute maximum ratings are those values beyond which damage to the device may occur.
Functional operation under these condition is not implied
Table 2. Thermal data
Symbol
R
thJC
R
thJA
Parameter
Thermal resistance junction-case
Thermal resistance junction-ambient
TO-220
3
50
TO-220FP
5
60
D²PAK
D²PAK/A
3
62.5
Unit
°C/W
°C/W
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