Analog Microelectronics, Inc.
AME8802
300mA CMOS LDO
n
General Description
The AME8802 family of positive, linear regulators fea-
ture low quiescent current (30µA typ.) with low dropout
voltage, making them ideal for battery applications. The
space-saving SOT-23-5 package is attractive for
"Pocket" and "Hand Held" applications.
These rugged devices have both Thermal Shutdown,
and Current Fold-back to prevent device failure under
the "Worst" of operating conditions.
An additional feature is a "Power Good" detector, which
pulls low when the output is out of regulation.
The AME8802 is stable with an output capacitance of
2.2µF or greater.
n
Features
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Very Low Dropout Voltage
Guaranteed 300mA Output
Accurate to within 1.5%
30µA Quiescent Current
Over-Temperature Shutdown
Current Limiting
Short Circuit Current Fold-back
Power Good Output Function
Power-Saving Shutdown Mode
Space-Saving SOT-25 (SOT-23-5)
Factory Pre-set Output Voltages
Low Temperature Coefficient
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Applications
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Functional Block Diagram
IN
Overcurrent
Shutdown
OUT
Instrumentation
Portable Electronics
Wireless Devices
Cordless Phones
PC Peripherals
Battery Powered Widgets
Electronic Scales
Thermal
Shutdown
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Typical Application
IN
AMP
R1
IN
PG
GND
OUT
EN
EN
V
ref
x 1 1 0 %
AME8802
C1
5V
1µF
OUT
PG
C2
2.2µF
V
ref
x 9 0 %
V
ref
= 1 . 2 1 5 V
**
R2
GND
** If output voltage specification is lower than 1.215V, Vref will be
trimmed to 1.2V.
1
Analog Microelectronics, Inc.
AME8802
300mA CMOS LDO
n
Pin Configuration
SOT-25 Top View
5
4
1. V
IN
2. GND
3. EN
1
2
3
4. PG
5. OUT
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Ordering Information
Part N umber
AME8802AEEV
AME8802BEEV
AME8802C EEV
AME8802D EEV
AME8802EEEV
AME8802FEEV
AME8802GEEV
AME8802HEEV
AME8802IEEV
AME8802JEEV
AME8802KEEV
AME8802LEEV
AME8802MEEV
AME8802NEEV
AME8802OEEV
AME8802TEEV
AME8802UEEV
Marking
AAKww
AALww
AAMww
AANww
AAOww
ABPww
AC Gww
AEHww
AEPww
AGRww
AHTww
AJMww
AJNww
AKQww
AKRww
ARVww
ASD ww
Output Voltage
3.3V
3.0V
2.8V
2.5V
3.8V
3.6V
3.5V
2.7V
3.4V
2.85V
3.7V
1.5V
1.8V
2.9V
3.1V
1.2V
3.2V
Package
SOT-25
SOT-25
SOT-25
SOT-25
SOT-25
SOT-25
SOT-25
SOT-25
SOT-25
SOT-25
SOT-25
SOT-25
SOT-25
SOT-25
SOT-25
SOT-25
SOT-25
Operating Temp. R ange
-40 C to +85 C
-40 C to +85 C
-40 C to +85 C
-40 C to +85 C
-40 C to +85 C
-40 C to +85 C
-40 C to +85 C
-40 C to +85 C
-40 C to +85 C
-40 C to +85 C
-40 C to +85 C
-40 C to +85 C
-40 C to +85 C
-40 C to +85 C
-40 C to +85 C
-40 C to +85 C
-40 C to +85 C
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
# represents the date code
Please consult AME sales office or authorized Rep./D istributor for other output voltage
and package type availability.
2
Analog Microelectronics, Inc.
AME8802
300mA CMOS LDO
n
Absolute Maximum Ratings
Parameter
Input Voltage
Output Current
Output Voltage
ESD Classification
Maximum
8
P
D
/ (V
IN
- V
O
)
GND - 0.3 to V
IN
+ 0.3
B
Unit
V
mA
V
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Recommended Operating Conditions
Parameter
Ambient Temperature Range
Junction Temperature
Rating
-40 to +85
-40 to +125
Unit
o
C
C
o
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Thermal Information
Parameter
Thermal Resistance (
θ
ja
)
Maximum
o
Unit
SOT-25
260
C/W
Internal Power Dissipation (P
D
)
(
∆
T = 100
o
C)
Maximum Junction Temperature
SOT-25
380
mW
150
o
C
Maximum Lead Temperature ( 10 Sec)
300
o
C
Caution: Stress above the listed absolute rating may cause permanent damage to the device
3
Analog Microelectronics, Inc.
AME8802
300mA CMOS LDO
n
Electrical Specifications
TA = 25
o
C unless otherwise noted
Parameter
Input Voltage
Output Voltage Accuracy
Symbol
V
IN
V
O
I
O
=300mA
V
O
=V
ON OM
-2.0%
I
O
=1mA
1.2V<V
O(NOM)
<=2.0V
2.0V<V
O(NOM)
<=2.8V
2.8V<V
O(NOM)
Output Current
Current Limit
Short Circuit Current
Quiescent Current
Ground Pin Current
I
O
I
LIM
I
SC
I
Q
I
GN D
V
O
>1.2V
V
O
>1.2V
V
O
<0.8V
I
O
=0mA
I
O
=1mA to 300mA
I
O
=1mA
V
IN
=V
O
+1 to V
O
+2
V
O
< 2.0V
2.0V<=V
O
< 4.0V
4.0V <= Vo
Load Regulation
Over Temerature Shutdown
Over Temerature Hysterisis
V
O
Temperature Coefficient
REG
LOAD
OTS
OTH
TC
f=1kHz
Power Supply Rejection
PSRR
I
O
=100mA
C
O
=2.2
µ
F
f=10Hz to 100kHz
I
O
=10mA
f=10kHz
f=100kHz
Co=2.2
µ
F
2.0
0
I
O
=1mA to 300mA
-0.15
-0.1
-0.4
-1
0.02
0.2
0.2
150
30
30
50
20
15
30
Vin
0.4
0.1
0.5
0.5
0
1
0.4
85
75
115
125
1
7
0.4
%V
O(NOM)
µ
A
V
V
%V
O(NOM)
µ
Vrms
V
V
µ
A
µ
A
µ
A
V
dB
300
300
450
150
30
35
0.15
0.1
0.4
1
300
50
See
chart
Test Condition
Min
Note 1
-1.5
Typ
Ma x
7
1.5
1300
400
300
mA
mA
mA
µ
A
µ
A
%
%
%
%
o
o
Units
V
%
Dropout Voltage
V
DR OPOU T
mV
Line Regulation
REG
LIN E
C
C
ppm/
o
C
Output Voltage Noise
eN
V
EH
V
EL
I
EH
I
EL
EN Input Threshold
V
IN
=2.7V to 7V
V
IN
=2.7V to 7V
V
EN
=V
IN
, V
IN
=2.7V to 7V
V
EN
=0V, V
IN
=2.7V to 7V
V
IN
=5V, V
O
=0V, V
EN
<V
EL
I
O
=0.4mA, V
EN
<V
EL
2.5V <=Vo <= 5.0V
EN Input Bias Current
Shutdown Supply Current
Shutdown Output Voltage
Output Under Voltage
I
SD
V
O,SD
V
UV
1.2V <= Vo < 2.5V
2.5V <=Vo <= 5.0V
Output Over Voltage
PG Leakage Current
PG Voltage Rating
PG Voltage Low
Note1:V
IN (m in)
=V
OU T
+V
DR OPOU T
V
OV
I
LC
V
PG
V
OL
1.2V <= Vo < 2.5V
V
PG
=7V
V
O
in regulation
I
SINK
=0.4mA
4
Analog Microelectronics, Inc.
AME8802
300mA CMOS LDO
n
Detailed Description
The AME8802 family of CMOS regulators contain a
PMOS pass transistor, voltage reference, error ampli-
fier, over-current protection, thermal shutdown, and
power good function.
The P-channel pass transistor receives data from the
error amplifier, over-current shutdown, and thermal pro-
tection circuits. During normal operation, the error am-
plifier compares the output voltage to a precision refer-
ence. Over-current and Thermal shutdown circuits be-
come active when the junction temperature exceeds
150
o
C, or the current exceeds 300mA. During thermal
shutdown, the output voltage remains low. Normal op-
eration is restored when the junction temperature drops
below 120
o
C.
The AME8802 switches from voltage mode to current
mode when the load exceeds the rated output current.
This prevents over-stress. The AME8802 also incor-
porates current foldback to reduce power dissipation
when the output is short circuited. This feature becomes
active when the output drops below 0.8volts, and re-
duces the current flow by 65%. Full current is restored
when the voltage exceeds 0.8 volts.
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Enable
The Enable pin normally floats high. When actively,
pulled low, the PMOS pass transistor shuts off, and all
internal circuits are powered down. In this state, the
quiescent current is less than 1µA. This pin behaves
much like an electronic switch.
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Power Good
The AME8802 includes the Power Good feature. Nor-
mally, Pin 4 is "Floating", however, when the output is
not within
±10%
of the specified voltage, it pulls low.
This can occur under the following conditions:
1)
2)
3)
4)
Input Voltage too low.
During Over-Temperature.
During Over-Current.
If output is pulled up.
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External Capacitors
The AME8802 is stable with an output capacitor to
ground of 2.2µF or greater. Ceramic capacitors have
the lowest ESR, and will offer the best AC performance.
Conversely, Aluminum Electrolytic capacitors exhibit
the highest ESR, resulting in the poorest AC response.
Unfortunately, large value ceramic capacitors are com-
paratively expensive. One option is to parallel a 0.1µF
ceramic capacitor with a 10µF Aluminum Electrolytic.
The benefit is low ESR, high capacitance, and low over-
all cost.
A second capacitor is recommended between the input
and ground to stabilize Vin. The input capacitor should
be at least 0.1uF to have a beneficial effect.
All capacitors should be placed in close proximity to
the pins. A "Quiet" ground termination is desirable.
This can be achieved with a "Star" connection.
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