AME, Inc.
AME1086
1.5A Low Dropout
Positive Voltage Regulator
n
General Description
The AME1086 is a 1.5A low-dropout positive voltage regu-
lator. It is available in fixed and adjustable output voltage
versions. Overcurrent and thermal protection are inte-
grated onto the chip. Output current will limit as it reaches
the pre-set current or temperature limit. At full rated
output current the dropout voltage is 1.4V (max.).
AME1086 series regulators provide excellent regulation
over line, load and temperature variations.
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Key Features
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Low dropout voltage 1.2V typically at 1.5A
Adjustable or 3.3V fixed voltage
Line regulation typically 0.015%
Load regulation typically 0.05%
Adjust pin (ADJ) current less than 90µA
Overcurrent protection
Thermal protection
Available in TO-220, TO-263, TO-252
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Applications
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High Efficiency Linear Regulators
Post Regulators for Switching Supplies
5V to 3.3V Voltage Converter
Battery Charger
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Functional Block Diagram
Input
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Typical Application
AME1086
V
IN
GND
V
OUT
Current
Limiting
Amplifier
Thermal
Protection
Output
4.75V to 5.25V
10µF Tan
10µF Tan
Load
Error
Amp.
Bandgap
Reference
ADJ/GND
Figure 2
Figure 1
1
AME, Inc.
AME1086
1.5A Low Dropout
Positive Voltage Regulator
n
Pin Configuration
To-263 Front View
To-263-2 Front View
AME 1086
1
2
3
AME 1086
1
2
3
ADJ/GND V
OUT
V
IN
ADJ/GND V
OUT
V
IN
To-252-2 Front View
TO-252-2 Front view
AME 1086
1
2
3
AME1086
1
ADJ/
GND
2
V
OUT
3
ADJ/GND V
OUT
V
IN
V
IN
To-220 Front View
AME1086
ADJ/GND
V
O U T
V
IN
2
AME, Inc.
AME1086
1.5A Low Dropout
Positive Voltage Regulator
n
Ordering Information
Part Number
AME1086ACBT
Marking
AME1086
ACBT
YYWW
AME1086
DCBT
YYWW
AME1086
ACDT
YYWW
AME1086
DCDT
YYWW
AME1086
ACDS
YYWW
AME1086
DCDS
YYWW
AME1086
ACCS
YYWW
AME1086
DCCS
YYWW
Output Voltage
ADJ
Package
TO-220
AME1086DCBT
3.3
TO-220
AME1086ACDT
ADJ
TO-263-3
AME1086DCDT
3.3
TO-263-3
AME1086ACDS
ADJ
TO-263-2
AME1086DCDS
3.3
TO-263-2
AME1086ACCS
ADJ
TO-252-2
AME1086DCCS
3.3
TO-252-2
* This differs from our standard part numbering scheme due to historical precedent
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Absolute Maximum Ratings
Parameter
Input Voltage
Thermal Resistance
(Junction to Case)
Thermal Resistance
(Junction to Ambient)
Operating Junction Temperature Range
Storage Temperature Range
Lead Temperature ( 10 sec )
TO-220
TO-263
TO-252
TO-220
TO-263
TO-252
T
J
T
STG
T
LEAD
θ
JA
Symbol Maximum
V
IN
θ
JC
7
2.5
2.5
15
50
60
90
0 to 125
-65 to 150
260
Units
V
0
C/W
0
C
3
AME, Inc.
AME1086
1.5A Low Dropout
Positive Voltage Regulator
n
Electrical Characteristics
AME1086AXXX
Parameter
Reference voltage
(adjustable voltage)
Line regulation
Load regulation
Dropout voltage
∆
V
OUT
,
∆
V
REF
= 1%
Current limit
Temperature Coefficient
Temperature stability
Minimum load current
RMS output noise
Ripple rejection ratio
AME1086DXXX
Parameter
Output voltage
(fixed voltage)
Line regulation
Load regulation
Dropout voltage
∆
V
OUT
,
∆
V
REF
= 1%
Current limit
Quiescent current
(fixed model)
Temperature Coefficient
Temperature stability
RMS output noise
Ripple rejection ratio
Symbol
V
REF
Reg
LINE
Reg
LOAD
V
D
I
S
T
C
T
S
I
O
V
N
R
A
V
IN
= 5V
I
O
= 10mA
Test Conditions
T
J
=25
0
C
T
J
=25
0
C
Over temp.
T
J
=25
0
C
Over temp.
T
J
=25
0
C
Over temp.
Min.
1.238
-
-
-
-
-
-
1.5
-
-
-
-
60
Typ.
1.250
0.015
0.035
0.05
0.2
1.2
1.3
-
0.005
0.5
5
0.003
72
Max.
1.262
1.275
0.2
0.2
0.3
0.4
1.4
-
-
-
-
10
-
-
Units
V
%
%
V
A
%/
O
C
%
mA
%V
0
dB
Over temp. 1.225
V
IN
= 2.75 - 7V
I
O
= 10mA
V
IN
= 5V
I
O
= 10mA - 1.5A
V
IN
= 2.75 - 7V
I
O
= 10mA - 1.5A
V
IN
= 2.75 - 7V, Over temp.
V
IN
= 2.75 - 7V, I
O
= 10mA - 1.5A
V
IN
= 5V, I
O
= 500mA, Over temp.
V
IN
= 5V
T
J
=25
0
C
V
IN
= 5V, I
O
= 1.5A, Over temp.
Symbol
Vo
Reg
LINE
Reg
LOAD
V
D
I
S
I
Q
T
C
T
S
V
N
R
A
V
IN
= 5V
I
O
= 0A
Test Conditions
T
J
=25 C
T
J
=25
0
C
Over temp.
T
J
=25
0
C
Over temp.
T
J
=25
0
C
Over temp.
0
Min.
3.267
-
-
-
-
-
-
1.5
-
-
-
-
60
Typ.
3.300
0.015
0.035
0.05
0.2
1.2
1.3
-
12
0.005
0.5
0.003
72
Max.
3.333
3.366
0.2
0.2
0.3
0.4
1.4
-
-
13
-
-
-
-
Units
V
%
%
V
A
mA
%/
0
C
%
%V
0
dB
Over temp. 3.234
V
IN
=4.5 - 7V
I
O
= 0A
V
IN
= 5V
I
O
= 0A - 1.5A
V
IN
= 4.5 - 7V
I
O
= 0A - 1.5A
V
IN
= 4.5 - 7V, Over temp.
V
IN
= 5V, Io=0A - 1.5A, Over temp.
V
IN
= 4.5 - 7V, I
O
= 0A - 1.5A
V
IN
= 5V, I
O
= 500mA, Over temp.
T
J
=25
0
C
V
IN
= 5V, I
O
= 1.5A, Over temp.
4
AME, Inc.
AME1086
1.5A Low Dropout
Positive Voltage Regulator
3. Current limit protection
AME1086 is protected against overload condi-
tions. Current protection is triggered at typi-
cally 3.0A.
4. Stability and load regulation
AME1086 requires a capacitor from V
OUT
to GND
to provide compensation feedback to the inter-
nal
gain stage. This is to ensure stability at
the output terminal. Typically, a 10µF tantalum
or
50µF aluminum electrolytic is sufficient.
Note: It is important that the ESR for this ca-
pacitor does not exceed 0.5Ω.
The output capacitor dose not have a theoreti-
cal upper limit and increasing its value will in-
crease stability. C
OUT
= 100µF or more is typi-
cal for high current regulator design.
V
OUT
V
REF
R1
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Application Description
1. Output voltage adjustment
Like most regulators, the AME1086 regulates the
output by comparing the output voltage to an
internally generated reference voltage. On the
adjustable version, the V
REF
is available exter-
nally as 1.25V between V
OUT
and ADJ. The
voltage ratio formed by R1 and R2 should be
set
to conduct 10mA (minimum output load).
The output voltage is given by the following
equation:
R2
) + I
ADJ
x R2
V
OUT
= V
REF
( 1 +
R1
On fixed versions of AME1086, the voltage divider
is provided internally.
V
IN
C
1
IN
ADJ
I
A DJ
50µA
OUT
R2
V
O U T
= V
R E F
(1+ R 2 ) + I
ADJ
x R2
R1
V
IN
For the adjustable version, the best load regu-
lation is accomplished when the top of the
resistor divider (R1) is connected directly to the
output pin of the AME1086. When so con-
nected, R
P
is not multiplied by the divider ratio.
For fixed output versions, the top of R1 is in-
ternally connected to the output and ground
pin can be connected to low side of the load.
R
P
Parasitic
Line Resistance
IN
ADJ
OUT
Figure 3
2. Thermal protection
AME1086 has thermal protection which limits
junction temperature to 150
O
C. However, de-
vice functionality is only guaranteed to a maxi-
mum junction temperature of +125
O
C.
The power dissipation and junction temperature
for AME1086 in TO-220 package are given by
P
D
= (V
IN
- V
OUT
) x I
OUT
T
JUNCTION
= T
AMBIENT
+ ( P
D
x
θ
JA
)
Note: T
JUNCTION
must not exceed 125
O
C
R1
(Connect R1 to case)
R
L
R2
Connect
R2 to load
Figure 4
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