Analog Microelectronics, Inc.
1
AME8841
600mA CMOS LDO
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Typical Application
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Functional Block Diagram
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Features
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Very Low Dropout Voltage
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Guaranteed 600mA Output
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Accurate to within 1.5%
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30
µ
A Quiescent Current
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Over-Temperature Shutdown
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Current Limiting
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Short Circuit Current Fold-back
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Power-Saving Shutdown Mode
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Space-Saving SO-8 Package
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Many fixed output voltages available
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Low Temperature Coefficient
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General Description
The AME8841 linear regulator features low quiescent cur-
rent (30
µ
A typ.) with low dropout voltage, making it ideal
for battery applications. The space-saving SO-8 pack-
age is attractive for "Pocket" and "Hand Held" applica-
tions.
These rugged devices have both Thermal Shutdown,
and Current Fold-back to prevent device failure under
the "Worst" of operating conditions.
The AME8841 is stable with an output capacitance of
2.2
µ
F or greater.
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Applications
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Instrumentation
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Portable Electronics
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Wireless Devices
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Cordless Phones
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PC Peripherals
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Battery Powered Widgets
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Electronic Scales
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Pin Configuration
SO-8 Top View
O U T
IN
G N D
E N
N C
N C
O U T
AME
8841
N C
AME8841
O U T
IN
C 3
2.2
µ
F
C 1
1
µ
F
G N D
O U T
5 V
E N
IN
A M P
G N D
O U T
IN
R 1
R 2
V
ref
= 1 . 2 1 5 V
Overcurrent
S h u t d o w n
Thermal
S h u t d o w n
E N
Analog Microelectronics, Inc.
2
600mA CMOS LDO
AME8841
Parameter
Maximum
Unit
Input Voltage
8
V
Output Current
P
D
/ (V
IN
- V
O
)
A
Input, Output Voltage
GND - 0.3 to V
IN
+ 0.3
V
ESD Classification
B
Parameter
Rating
Unit
Ambient Temperature Range
-40 to +85
o
C
Junction Temperature
-40 to +125
o
C
Parameter
Maximum
Unit
Thermal Resistance (
ja
)
123.7
o
C / W
Internal Power Dissipation (P
D
)
(
T = 100
o
C)
810
mW
Maximum Junction Temperature
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
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Absolute Maximum Ratings:
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Recomended Operating Conditions:
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Thermal Paramters
Analog Microelectronics, Inc.
3
AME8841
600mA CMOS LDO
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Ordering Information
P art N um ber
Markin g
Ou tpu t
P ackage
Op erating Temp .
A M E 8841A E HA
8841
A E HA
y y ww
3.3V
S O -8
-40
O
C to + 85
O
C
A M E 8841B E HA
8841
B E HA
y y ww
3.0V
S O -8
-40
O
C to + 85
O
C
A M E 8841CE HA
8841
CE HA
y y ww
2.8V
S O -8
-40
O
C to + 85
O
C
A M E 8841DE HA
8841
DE HA
y y ww
2.5V
S O -8
-40
O
C to + 85
O
C
A M E 8841E E HA
8841
E E HA
y y ww
3.8V
S O -8
-40
O
C to + 85
O
C
A M E 8841FE HA
8841
FE HA
y y ww
3.6V
S O -8
-40
O
C to + 85
O
C
A M E 8841G E HA
8841
G E HA
y y ww
3.5V
S O -8
-40
O
C to + 85
O
C
A M E 8841HE HA
8841
HE HA
y y ww
2.7V
S O -8
-40
O
C to + 85
O
C
A M E 8841IE HA
8841
IE HA
y y ww
3.4V
S O -8
-40
O
C to + 85
O
C
A M E 8841JE HA
8841
JE HA
y y ww
2.85V
S O -8
-40
O
C to + 85
O
C
A M E 8841K E HA
8841
K E HA
y y ww
3.7V
S O -8
-40
O
C to + 85
O
C
A M E 8841LE HA
8841
LE HA
y y ww
1.5V
S O -8
-40
O
C to + 85
O
C
A M E 8841M E HA
8841
M E HA
y y ww
1.8V
S O -8
-40
O
C to + 85
O
C
A M E 8841NE HA
8841
NE HA
y y ww
2.9V
S O -8
-40
O
C to + 85
O
C
A M E 8841O E HA
8841
O E HA
y y ww
3.1V
S O -8
-40
O
C to + 85
O
C
A M E 8841RE HA
8841
RE HA
y y ww
2.65V
S O -8
-40
O
C to + 85
O
C
P leas e c ons ult A M E s ales offic e or authoriz ed Rep./Dis tributor for other output voltage
and pac k age ty pe availability .
Analog Microelectronics, Inc.
4
600mA CMOS LDO
AME8841
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Electrical Specifications
Parameter
Symbol
Min
Typ
Max
Units
Input Voltage
V
IN
Note 1
7
V
Output Voltage Accuracy
V
O
-1.5
1.5
%
1.4V<V
O(NOM)
<=2.0V
1400
Dropout Voltage
V
DROPOUT
2.0V<V
O(NOM)
<=2.8V
800
2.8V<V
O(NOM)
600
Output Current
I
O
600
mA
Current Limit
I
LIM
600
800
mA
Short Circuit Current
I
SC
300
600
mA
Quiescent Current
I
Q
30
50
µ
A
Ground Pin Current
I
GND
30
50
µ
A
V
O
< 2.0V
-0.15
0.15
%
4.0V > V
O
>= 2.0V
-0.1
0.02
0.1
%
V
O
>= 4.0V
-0.4
0.4
%
Over Temerature Shutdown
OTS
150
o
C
Over Temerature Hysterisis
OTH
30
o
C
V
O
Temperature Coefficient
TC
30
ppm/
o
C
f=1kHz
50
PSRR
f=10kHz
20
dB
f=100kHz
15
V
EH
2.0
Vin
V
V
EL
0
0.4
V
I
EH
0.1
µ
A
I
EL
0.5
µ
A
Shutdown Supply Current
I
SD
0.5
1
µ
A
Note1:V
IN(min)
=V
OUT
+V
DROPOUT
mV
V
O
>1.2V
V
O
>1.2V
TA = 25
o
C unless otherwise noted
Test Condition
I
O
=1mA
I
O
=600mA
V
O
=V
ONOM
-2.0%
I
O
=1mA to 600mA
See
chart
V
O
<0.8V
I
O
=0mA
mVrms
Power Supply Rejection
I
O
=100mA
C
O
=2.2
µ
F
30
EN Input Threshold
V
IN
=2.7V to 7V
V
IN
=2.7V to 7V
Co=2.2
µ
F
EN Input Bias Current
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
Line Regulation
REG
LINE
I
O
=5mA
V
IN
=V
O
+1 to V
O
+2
Output Voltage Noise
eN
f=10Hz to 100kHz
I
O
=10mA,C
BYP
=0
µ
F
Analog Microelectronics, Inc.
5
AME8841
600mA CMOS LDO
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Detailed Description
The AME8841 family of CMOS regulators contain a
PMOS pass transistor, voltage reference, error amplifier,
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 110
o
C.
The AME8841 switches from voltage mode to current mode
when the load exceeds the rated output current. This
prevents over-stress. The AME8841 also incorporates
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 reduces the
current flow by 65%. Full current is restored when the
voltage exceeds 0.8 volts.
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External Capacitors
The AME8841 is stable with an output capacitor to ground
of 2.2
µ
F 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 comparatively expen-
sive. One option is to parallel a 0.1
µ
F ceramic capacitor
with a 10
µ
F Aluminum Electrolytic. The benefit is low
ESR, high capacitance, and low overall cost.
A second capacitor is recommended between the input
and ground to stabilize Vin. The input capacitor should
be at least 0.1
µ
F 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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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 1
µ
A. This pin behaves
much like an electronic switch.
Analog Microelectronics, Inc.
6
600mA CMOS LDO
AME8841
Load Step ( 1mA-600mA)
TIME ( 20mS/DIV)
I
L
(200mA/DIV) Vo(10mV/DIV)
I
L o a d
Output
C
L
=2.2
µ
F
CIN=2.2
µ
F
0
0
0.05
0.1
0.15
0.2
0.25
0.3
2
2.5
3
3.5
4
4.5
5
5.5
I
L O A D
= 6 0 0 m A
Drop Out Voltage vs. Output Voltage
Drop Out Voltage (V)
Output Voltage (V)
0
5
10
15
20
25
30
35
40
45
0
1
2
3
4
5
6
7
8
Ground Current vs. Input Voltage
Ground Current (
µ
µ
µ
µ
A)
Input Voltage (V)
85
O
C
25
O
C
-80
-70
-60
-50
-40
-30
-20
-10
0
1.0E+01
1.0E+03
1.0E+05
1.0E+07
Power Supply Rejection Ratio
PSRR (dB)
Frequency (Hz)
1 0 0 m A
1 0 m A
1 m A
100
µ
A
1 0 0 m A
100
µ
A
C
L
=2.2
µ
F Tantalum
C
B Y P
=0
10
100
600
0.1
1.0
8.0
Safe Operating Area
Output Current (mA)
Input-Output Voltage Differential (V)
8 8 0 7 A E H A
8 8 4 1 A E H A
Analog Microelectronics, Inc.
7
AME8841
600mA CMOS LDO
Short Circuit Response
V
OUT
(1V/DIV) I
OUT
(200mV/DIV)
TIME (2mS/DIV)
C
L O A D
=2.2
µ
F
C
I N
= 1
µ
F
R
L O A D
< 1 0 0 m
0
0
Chip Enable Transient Response
TIME ( 1mS/DIV)
C
L
=2
µ
F
R
L
=10
Output (1V/DIV) Enable (2V/DIV)
Line Transient Response
V
OUT
(10mV/DIV) V
IN
(1V/DIV)
C
L O A D
=2.2
µ
F
I
L O A D
= 1 m A
V
O U T D C
=3.3V
V
I N D C
=4.5V
TIME (200mS/DIV)
Current Limit Response
I
OUT
(200mA/DIV) V
OUT
(1V/DIV)
TIME (2mS/DIV)
C
L O A D
=2.2
µ
F
C
I N
=1.0
µ
F
R
L O A D
=3.3
V
O U T N O M
=3.3V
Overtemperature Shutdown
V
OUT
(1V/DIV) I
OUT
(200mA/DIV)
TIME (0.5Sec/DIV)
R
L O A D
=6.6
0
0
Noise Measurement
TIME (20mS/DIV)
Vo (1mV/ DIV)
C
L
= 2.2
µ
F
NO FILTER
Analog Microelectronics, Inc.
8
600mA CMOS LDO
AME8841
2.620
2.625
2.630
2.635
2.640
2.645
2.650
2.655
2.660
-20
0
20
40
60
80
Tem perature (
0
C)
Vout @ Vin=Vout+2V (V)
Vout vs. Temp.
0.30
0.35
0.40
0.45
0.50
0.55
0.60
0.65
-20
0
20
40
60
80
Tem perature (
0
C)
Shut Down Current (uA)
Shut Down Current vs.
Temp.
26
28
30
32
34
36
38
40
-20
0
20
40
60
80
Tem perature (
0
C)
Quiescent Current (uA)
Quiescent Current vs.Temp.
-0.50
-0.45
-0.40
-0.35
-0.30
-0.25
-0.20
-20
0
20
40
60
80
Tem perature (
0
C)
EN pin LO bias current (uA)
EN pin vs. Temp.
360
380
400
420
440
460
480
500
-20
0
20
40
60
80
Tem perature (
0
C)
Dropout Voltage @ 600mA (mV)
Dropout Voltage vs. Temp.
0.30
0.35
0.40
0.45
0.50
0.55
-20
0
20
40
60
80
Tem perature (
0
C)
Load Regulation (%)
Load Regulation vs. Temp.
Analog Microelectronics, Inc.
9
AME8841
600mA CMOS LDO
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Package Dimension
SO-8
MIN
MAX
MIN
MAX
A
1.35
1.75
0.053
0.069
A
1
0.10
0.25
0.004
0.010
A2
--
--
--
--
B
0.33
0.51
0.013
0.020
C
0.19
0.25
0.007
0.010
D
4.80
5.00
0.189
0.1970
E
3.80
4.00
0.150
0.157
e
--
--
--
--
H
5.80
6.20
0.228
0.244
L
0.40
1.27
0.016
0.050
y
--
0.10
0.004
0
°
8
°
0
°
8
°
SYMBOLS
MILLIMETERS
INCHES
Life Support Policy:
These products of Analog Microelectronics, Inc. are not authorized for use as critical components in life-
support devices or systems, without the express written approval of the president
of Analog Microelectronics, Inc.
Analog Microelectronics, Inc. reserves the right to make changes in the circuitry and specifications of its
devices and advises its customers to obtain the latest version of relevant information.
©
Analog Microelectronics, Inc. , August 2001
Document: 2006-DS8841-C
Corporate Headquarters
Asia Pacific Headquarters
Analog Microelectronics, Inc.
AME, Inc.
3100 De La Cruz Blvd. Suite 201
2F, NO. 187 Kang-Chien Road, Nei-Hu Dist.,
Santa Clara, CA. 95054-2046
Taipei 114, Taiwan, R.O.C.
Tel : (408) 988-2388
Tel : 886 2 2627-8687
Fax: (408) 988-2489
Fax : 886 2 2659-2989
www.analogmicro.com
E-Mail: info@analogmicro.com
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