Analog Microelectronics, Inc.
AME8807
600mA CMOS LDO
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General Description
The AME8807 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 SO-8 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.
The AME8807 is stable with an output capacitance of
2.2µF or greater.
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Features
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Very Low Dropout Voltage
Guaranteed 600mA Output
Accurate to within 1.5%
30µA Quiescent Current
Over-Temperature Shutdown
Current Limiting
Short Circuit Current Fold-back
Power-Saving Shutdown Mode
Space-Saving SO-8 Package
User Adjustable Output Voltages
Low Temperature Coefficient
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Applications
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Functional Block Diagram
IN
Overcurrent
Shutdown
Instrumentation
Portable Electronics
Wireless Devices
Cordless Phones
PC Peripherals
Battery Powered Widgets
Electronic Scales
OUT
Thermal
Shutdown
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Typical Application
IN
C1
OUT
EN
IN
AME8807
PG
GND ADJ
EN
V
ref
x110%
OUT
C2
R1
100p
C3
2.2µF
R2
PG
AMP
ADJ
5V
1µF
V
ref
x90%
V
ref
= 1 . 2 1 5 V
GND
V
OUT
= 1.215 ( R1/R2 +1 )
C2 is unnecessary if R1 or R2 < 20kohms
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Analog Microelectronics, Inc.
AME8807
600mA CMOS LDO
n
Pin Configuration
SO-8 Top View
SO-8 Top View
IN
GND
GND
EN
OUT
GND
GND
ADJ
OUT
ADJ
GND
NC
IN
NC
NC
EN
AME8807AEHA
AME8807BEHA
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Ordering Information
Part Number
AME8807AEHA
Marking
8807
AEHA
yyww
8807
BEHA
yyww
Output Voltage Package
Adjustable
SO-8
Operating Temp. Range
-40
O
C to +85
O
C
AME8807BEHA
Adjustable
SO-8
-40
O
C to +85
O
C
Please consult AME sales office or authorized Rep./Distributor for other package type availability.
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Analog Microelectronics, Inc.
AME8807
600mA CMOS LDO
n
Absolute Maximum Ratings:
Parameter
Input Voltage
Output Current
Output Voltage
ESD Classification
Maximum
8
Unit
V
A
V
P
D
/ (V
IN
- V
O
)
GND - 0.3 to V
IN
+ 0.3
B
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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
Package
8807AEHA
Thermal Resistance (
θ
ja
)
8807BEHA
8807AEHA
Internal Power Dissipation (P
D
) (
∆
T = 100 C)
8807BEHA
Maximum Junction Temperature
Maximum Lead Temperature ( 10 Sec)
810
150
300
o
o
Maximum
124
o
Unit
C/W
124
810
mW
C
C
o
Caution: Stress above the listed absolute rating may cause permanent damage to the device
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Analog Microelectronics, Inc.
AME8807
600mA 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
=600mA
V
O
=V
ONOM
-2.0%
I
O
=1mA
1.5V<V
O(NOM)
<=2.0V
2.0V<V
O(NOM)
<=2.8V
2.8V<V
O(NOM)
<3.8V
Output Current
Current Limit
Short Circuit Current
Quiescent Current
Ground Pin Current
Line Regulation
Load Regulation
Over Temerature Shutdown
Over Temerature Hysterisis
V
O
Temperature Coefficient
I
O
I
LIM
I
SC
I
Q
I
GND
REG
LINE
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
Co=100
µ
F
0.02
V
O
>1.2V
V
O
>1.2V
V
O
<0.8V
I
O
=0mA
I
O
=1mA to 600mA
I
O
=5mA
V
IN
=V
O
+1 to V
O
+2
V
O
< 2.0V
V
O
>= 2.0V
0.02
0.2
150
30
30
50
20
15
30
20
0.04
µ
Vrms
µ
A
V
V
V
µ
A
µ
A
µ
A
dB
600
600
800
300
30
30
600
50
50
0.15
0.1
1
See
chart
Test Condition
Min
Note 1
-1.5
Typ
Max
8
1.5
1400
800
600
mA
mA
mA
µ
A
µ
A
%
%
%
o
o
Units
V
%
Dropout Voltage
V
DROPOUT
mV
I
O
=1mA to 600mA
C
C
ppm/
o
C
Output Voltage Noise
ADJ Input Bias Current
ADJ Reference Voltage
EN Input Threshold
eN
I
ADJ
V
REF
V
EH
V
EL
I
EH
I
EL
I
SD
1.203 1.215 1.227
V
IN
=2.7V to 8V
V
IN
=2.7V to 8V
V
EN
=V
IN
, V
IN
=2.7V to 8V
V
EN
=0V, V
IN
=2.7V to 8V
V
IN
=5V, V
O
=0V, V
EN
<V
EL
0.5
2.0
0
Vin
0.4
0.1
0.5
1
EN Input Bias Current
Shutdown Supply Current
Note1:V
IN(min)
=V
OUT
+V
DROPOUT
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Analog Microelectronics, Inc.
AME8807
600mA CMOS LDO
n
Detailed Description
The AME8807 family of CMOS regulators contain a
PMOS pass transistor, voltage reference, error ampli-
fier, over-current protection, and thermal shutdown.
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 600mA. During thermal
shutdown, the output voltage remains low. Normal op-
eration is restored when the junction temperature drops
below 120
o
C.
The AME8807 switches from voltage mode to current
mode when the load exceeds the rated output current.
This prevents over-stress. The AME8807 also incor-
porates current foldback to reduce power dissipation
when the output is short circuited. This feature becomes
active when the output drops below 0.8 volts, 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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ADJ
The ADJ pin is the positive input to the error amplifier
which, due to the pmos pass element inversion, means
it is actually the negative input of the LDO feedback loop.
The feedback works to keep the voltage at the ADJ pin
1.215V with respect to ground. Since the internal cir-
cuitry at the ADJ pin is essentially an ESD protected
CMOS gate the input current at the ADJ pin is virtually
zero.
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External Capacitors
The AME8807 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 0.1µF 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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