ETC L1085S

3A Adjustable Low Dropout
Linear Regulator (LDO)
NIKO-SEM
L1085
TO-252,263,220
GENERAL DESCRIPTION
FEATURES
The L1085 is a positive and low dropout
three-terminal voltage regulator with 3A output current capability. This device is designed for use in low voltage applications that
offers lower dropout voltage and faster transient response.
z Very easy to use, it requires only two
external resistors to set the output voltage
z Low dropout voltage:
1.3V typical at up to 3A
z Low ground current
z Fast transient response
z Current & thermal limiting
z Line regulation: 0.5% typical
z Load regulation: 0.5% typical
z TO-220, TO-263 and TO-252 packages
This device is fully protected against over
current faults, over temperature operation,
reversed input polarity, reversed lead insertion, transient voltage spike …etc.
On-Chips trimming the reference voltage to
1% and features the low dropout of maximum 1.45 volts.
APPLICATIONS
z High current microprocessor supplies
z Low voltage logic supply
z Powering VGA & sound card
z Portable instrumentation
z Constant current regulator
z Post regulator for switching power supply
The L1085 Series regulators are available
in the popular industry standard TO-220
TO-263 and TO-252 packages.
TYPICAL APPLICATION
Vin
Vout
L1085
IN
OUT
ADJ
Cin
Vref
R1
+
+
10uF
Cout
10uF
R2
Iadj
Vo = Vref (1+R2/R1) + Iadj x R2
1. Cin needed if device is far from from filter capacitors.
2. Cout required for stability.
- Basic Adjustable Regulator Circuit -
1
MAY-31-2001
3A Adjustable Low Dropout
Linear Regulator (LDO)
NIKO-SEM
L1085
TO-252,263,220
ABSOLUTE MAXIMUM RATINGS
z Maximum Supply Voltage
z Operating Junction
Temperature Range
z Storage Temperature
Range
z Lead Temperature
(Soldering, 10 Seconds)
7V
Internally
Limited
z Power Dissipation
z Thermal Resistance
Junction to Case, θJC
z Thermal Resistance
Junction to Ambient, θJA
TO-263
TO-252
TO-220
5 °C/W
0 to 125 °C
-40 to 150 °C
260 °C
60 °C/W
70 °C/W
50 °C/W
ELECTRICAL CHARACTERISTICS (Unless otherwise specified, TA = 25 °C.)
Parameter
Reference Voltage
Dropout Voltage
Line Regulation
Load Regulation
Minimum Load
Current
Symbol
VREF
Test Conditions
Typical
VIN = 5V, IOUT = 10mA
1.25V
VD
ΔVREF = 1%, IOUT = 3A
REG(LINE) (VOUT + 1.5V) ≤ VIN ≤ 7V, IOUT = 10mA
REG(LOAD) (VIN -VOUT) = 3V, 10mA ≤ IOUT ≤ 3A
1.3V
0.5%
0.5%
1.5V ≤ (VIN -VOUT) ≤ 5.75V
10mA
IO
Adjust Pin Current
Current Limit
IADJ
ICL
RMS Output Noise
VN
Ripple Rejection
Ratio
RA
VIN - VOUT = 2V
Limits
1.23VMin
1.27VMax
1.45V
2%
2.5%
55µA
5.0A
0.003%
of VOUT
100µA
4.0A (Min)
72dB
60dB (Min)
f = 120Hz, CADJ = 22µF for ADJ pin,
VIN = 5V, IOUT = 3A
DEVICE SELECTION GUIDE
Device
L1085D
Package
TO-252
Marking
L1085D
L1085S
L1085S3
TO-263 (2-Lead) TO-263 (3-Lead)
L1085S
2
L1085S3
L1085T
TO-220
L1085T
MAY-31-2001
NIKO-SEM
3A Adjustable Low Dropout
Linear Regulator (LDO)
L1085
TO-252,263,220
PIN CONFIGURATIONS
Pin #
Function
1
Adjust
2
Output
3
Input
Note: TAB is Output Pin
3
MAY-31-2001
NIKO-SEM
3A Adjustable Low Dropout
Linear Regulator (LDO)
L1085
TO-252,263,220
TO-263 (D2PAK) MECHANICAL DATA
mm
Dimension
mm
Min.
Typ.
Max.
A
14.5
15
15.8
B
4.2
C
1.20
D
Dimension
Min.
Typ.
Max.
H
1.0
1.5
1.8
4.7
I
9.8
1.35
J
6.5
K
1.5
2.8
E
0.3
F
-0.102
G
8.5
0.4
9
0.5
L
0.7
0.203
M
4.83
9.5
N
4
10.3
1.4
5.08
5.33
MAY-31-2001
NIKO-SEM
3A Adjustable Low Dropout
Linear Regulator (LDO)
L1085
TO-252,263,220
TO-263 (D2PAK) MECHANICAL DATA
mm
Dimension
mm
Min.
Typ.
Max.
A
14.5
15
15.8
B
4.2
C
1.20
D
Dimension
Min.
Typ.
Max.
H
1.0
1.5
1.8
4.7
I
9.8
1.35
J
6.5
K
1.5
2.8
E
0.3
F
-0.102
G
8.5
0.4
9
0.5
L
0.7
0.203
M
4.83
9.5
N
5
10.3
1.4
5.08
5.33
MAY-31-2001
NIKO-SEM
3A Adjustable Low Dropout
Linear Regulator (LDO)
L1085
TO-252,263,220
TO-220 (3-Lead) MECHANICAL DATA
mm
Dimension
mm
Min.
Typ.
Max.
A
9.78
10.16
10.54
B
2.61
2.74
2.87
C
Dimension
20
Min.
Typ.
Max.
H
2.4
2.54
2.68
I
1.19
1.27
1.35
J
4.4
4.6
4.8
D
28.5
28.9
29.3
K
1.14
1.27
1.4
E
14.6
15.0
15.4
L
2.3
2.6
2.9
F
8.4
8.8
9.2
M
0.26
0.46
0.66
G
0.72
0.8
0.88
N
6
7°
MAY-31-2001
NIKO-SEM
3A Adjustable Low Dropout
Linear Regulator (LDO)
L1085
TO-252,263,220
TO-252 (DPAK) MECHANICAL DATA
mm
Dimension
Min.
Typ.
mm
Max.
Dimension
Min.
Typ.
Max.
A
9.35
10.1
H
B
2.2
2.4
I
6.4
6.6
C
0.48
0.6
J
5.2
5.4
D
0.89
1.5
K
0.6
1
E
0.45
0.6
L
0.64
0.9
F
0.03
0.23
M
4.4
4.6
G
6
6.2
N
7
0.8
MAY-31-2001