1
L1087 Series
SOT-89,TO-92
AUG-30-2001
0.8A Fixed and Adjustable Low Dropout
Linear Regulator (LDO)
NIKO-SEM
GENERAL DESCRIPTION
The L1087 Series are positive and low
dropout three-terminal voltage regulators
with 0.8A output current capability. These
devices are designed for use in low voltage
applications that offers lower dropout volt-
age and faster transient response.
These devices are fully protected against
over current faults, over temperature oper-
ation, reversed input polarity, reversed lead
insertion, transient voltage spike ...etc.
On-Chips trimming the reference voltage to
1% and features the low dropout of maxi-
mum 1.45 volts.
The L1087 Series regulators offer fixed and
adjustable voltage options available in the
space saving SOT-89 & TO-92 package.
FEATURES
Fixed 3.3V or adjustable output voltage
Low dropout voltage
Low ground current
Fast transient response
Current & thermal limiting
Line regulation: 0.5% typical
Load regulation: 0.5% typical
Available in SOT-89 & TO-92 package
APPLICATIONS
Low voltage micro-controllers
Battery Chargers
5V to 3.3V linear regulators
Motherboard clock supplies
Post regulator for switching supplies
TYPICAL APPLICATION
- Basic Adjustable Regulator Circuit -
- Fixed Voltage Regulator -
OUT
2. Cout required for stability.
+
Cout
10uF
Vin > 4.75V
GND
1. Cin needed if device is far from filter capacitors.
Vout = 3.3V
+
Cin
10uF
RL
L1087-3.3
IN
IN
OUT
Iadj
ADJ
Vref
R2
+
Cin
10uF
1. Cin needed if device is far from filter capacitors.
L1087
2. Cout required for stability.
R1
Vo = Vref (1+R2/R1) + Iadj x R2
Vout
Vin
+
Cout
10uF
2
L1087 Series
SOT-89,TO-92
AUG-30-2001
0.8A Fixed and Adjustable Low Dropout
Linear Regulator (LDO)
NIKO-SEM
ABSOLUTE MAXIMUM RATINGS
Maximum Supply Voltage
15V*
Operating Junction
Temperature Range
0 to 125 C
Power Dissipation
Internally
Limited
Storage Temperature
Range
-40 to 150 C
Thermal Resistance
Junction to Case,
JC
18 C/W
Lead Temperature
(Soldering, 10 Seconds)
260 C
Thermal Resistance
Junction to Ambient,
JA
160 C/W
* When considering short circuits to ground, the maximum input-to-output differential voltage shall not be allowed
greater than approximate 2~3V at values of supply voltage in excess of 10V, continuous short-circuits can exceed
the power dissipation ratings and cause eventual destruction.
ELECTRICAL CHARACTERISTICS
(Unless otherwise specified, T
A
= 25 C)
Parameter
Symbol
Test Conditions
Typical
Limits
Reference Voltage
(Adjustable version)
V
REF
V
IN
= 5V, I
OUT
= 10mA
1.25V
1.23V
Min
1.27V
Max
Output Voltage
(Fixed version)
V
O
V
IN
= 5V, I
OUT
= 10mA
V
O
0.98V
O(Min)
1.02V
O(Max)
Dropout Voltage
V
D
V
REF
= 1%, I
OUT
= 0.8A
1.2V 1.45V
Line Regulation
REG
(LINE)
(V
OUT
+ 1.5V)
V
IN
15V, I
OUT
= 10mA 0.5% 2%
Load Regulation
REG
(LOAD)
(V
IN
-V
OUT
) = 2V, 10mA
I
OUT
0.8A
0.5% 2.5%
Minimum Load
Current
I
O
1.5V
(V
IN
-V
OUT
)
5.75V
10mA
Adjust Pin Current
I
ADJ
55
A 100
A
Current Limit
I
CL
V
IN
- V
OUT
= 2V
1.2A
0.9A (Min)
RMS Output Noise
V
N
0.003%
of V
OUT
Ripple Rejection
Ratio
R
A
f = 120Hz, C
ADJ
= 22
F for ADJ pin,
V
IN
= 5V, I
OUT
= 0.8A
72dB 60dB
(Min)
3
L1087 Series
SOT-89,TO-92
AUG-30-2001
0.8A Fixed and Adjustable Low Dropout
Linear Regulator (LDO)
NIKO-SEM
ELECTRICAL CHARACTERISTICS FOR FIXED 3.3V
(Unless otherwise specified, TA = 25 C)
Parameter
Symbol
Test Conditions
Typical
Limits
Output Voltage
(Fixed version)
V
O
V
IN
= 5V, I
OUT
= 10mA
V
O
3.234V
(Min)
3.367V
(Max)
Dropout Voltage
V
D
V
O
= 1%, I
OUT
= 0.8A
1.2V 1.45V
Line Regulation
REG
(LINE)
(V
OUT
+ 1.5V)
V
IN
15V, I
OUT
= 10mA 0.5% 2.0%
Load Regulation
REG
(LOAD)
(V
IN
-V
OUT
) = 2V, 10mA
I
OUT
0.8A
0.5% 2.0%
Minimum Load
Current
I
O
1.5V
(V
IN
-V
OUT
)
5.75V
10mA
GND Pin Current
I
GND
55
A 100
A
Current Limit
I
CL
V
IN
- V
OUT
= 2V
1.2A
0.9A (Min)
RMS Output Noise
V
N
0.003%
of V
OUT
Ripple Rejection
Ratio
R
A
f = 120Hz, Co=22Uf,V
IN
= 5V,
I
OUT
= 0.8A
72dB 60dB
(Min)
DEVICE SELECTION GUIDE
Device
L1087C L1087C-3.3
L1087N-3.3
Voltage Version
Adjustable 3.3V
3.3V
Package
SOT-89 SOT-89 TO-92
Marking
L1087 87-3.3 87N-3.3
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L1087 Series
SOT-89,TO-92
AUG-30-2001
0.8A Fixed and Adjustable Low Dropout
Linear Regulator (LDO)
NIKO-SEM
SOT-89 MECHANICAL DATA
mm
mm
Dimension
Min. Typ. Max.
Dimension
Min. Typ. Max.
A 4.3 4.5 4.7 H 1.4 1.5 1.6
B 1.6 1.7 1.8 I 2.8 3.0 3.2
C 0.4 0.5 0.6 J 1.3 1.5 1.7
D 2.4 2.5 2.6 K 3.8 4.2 4.6
E 0.8 1.2 1.4 L 0.3 0.4 0.5
F
0.4
0.45
0.5
M
G
0.4
0.5
0.6
N
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