Analog Microelectronics, Inc.
AME8817
NARY
RELIMI
P
1.5A CMOS LDO
n
General Description
The AME8817 family of positive, linear regulators fea-
ture low quiescent current (35µA typ.) with low dropout
voltage, making them ideal for battery applications.
Output voltages are set at the factory and trimmed to
1.5% accuracy.
These rugged devices have both thermal shutdown, and
current fold-back to prevent device failure under the "worst"
of operating conditions.
In applications requiring a low noise, regulated supply,
place a 1000pF capacitor between Bypass and Ground.
An additional feature is a "Power Good" detector, which
pulls low when the output is out of regulation.
The AME8817 is stable with an output capacitance of
4.7µF or greater.
n
Features
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Very Low Dropout Voltage
Guaranteed 1.5A Output
Accurate to within 1.5%
35µA Quiescent Current Typically
Over-Temperature Shutdown
Current Limiting
Short Circuit Current Fold-back
Noise Reduction Bypass Capacitor
Power Good Output
Power-Saving Shutdown Mode
Space-Saving DDPAK-7 Package
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Low Temperature Coefficien
t
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Applications
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Functional Block Diagram
IN
OUT
Instrumentation
Portable Electronics
Wireless Devices
PC Peripherals
Battery Powered Widgets
Overcurrent
Shutdown
Thermal
Shutdown
n
Typical Application
R1
IN
BYP (or ADJ)
IN
BYP
GND
OUT
AME8817
AMP
EN
OUT
PG
EN
PG
C1
5V
C2
C3
1
µF
1nF
4.7
µF
1.24V
R2
GND
1
Analog Microelectronics, Inc.
AME8817
RY
LIMINA
PRE
1.5A CMOS LDO
n
Pin Configuration
DDPAK-7 (TO-263) Top View
AME8817AEDZXXX
AME8817BEDZXXX
1
2
3
4
5
6
7
1.
2.
3.
4.
EN
PG
V
IN
GND
5. V
OUT
6. V
OUT
7. BYP
1
2
3
4
5
6
7
1.
2.
3.
4.
EN
PG
V
IN
GND
5. V
OUT
6. V
OUT
7. ADJ
n
Ordering Information
Output
Voltage
1.50
Package Type
DDPAK-7
AME8817AEDZ150
MARKING
AME8817
AEDZ150
yyww
AME8817
AEDZ180
yyww
AME8817
AEDZ250
yyww
AME8817
AEDZ330
yyww
AME8817
AEDZ475
yyww
AME8817
AEDZ500
yyww
AME8817
BEDZADJ
yyww
1.80
AME8817AEDZ180
2.50
AME8817AEDZ250
3.30
AME8817AEDZ330
4.75
AME8817AEDZ475
5.00
AME8817AEDZ500
ADJ
AME8817BEDZADJ
Please consult AME sales office or authorized Rep./Distributor for other output voltages, package types or pin configurations.
2
Analog Microelectronics, Inc.
AME8817
NARY
RELIMI
P
1.5A CMOS LDO
n
Absolute Maximum Ratings:
Parameter
Input Voltage
Output Current
Output Voltage
ESD Classification
Maximum
8
Unit
V
mA
V
P
D
/ (V
IN
- V
O
)
GND - 0.3 to V
IN
+ 0.3
B
n
Recommended operating Conditions:
Parameter
Ambient Temperature Range
Junction Temperature
Rating
-40 to +85
-40 to +125
Unit
o
C
C
o
n
Thermal Information
Parameter
Thermal Resistance (
θ
jc
)
Internal Power Dissipation (P
D
)
Maximum Junction Temperature
Maximum Lead Temperature ( 10 Sec)
(
∆
T = 100
o
C)
Maximum
60
2.7
150
300
o
Unit
C/W
W
o
C
C
o
Caution: Stress above the listed absolute rating may cause permanent damage to the device
3
Analog Microelectronics, Inc.
AME8817
RY
LIMINA
PRE
1.5A CMOS LDO
n
Electrical Specifications
TA = 25
o
C unles s otherwis e noted
P a ra m e te r
Input V oltage
Output V oltage A c c urac y
S ym bol
V
IN
V
O
I
O
= 1m A to 1.5A
I
O
= 1500m A
V
O
= V
O N O M
-2.0%
1.5V < = V
O N O M
< = 2.0V
2.0V < V
O N O M
< = 2.8V
2.8V < V
O N O M
< 3.8V
Output Current
Current Lim it
S hort Circ uit Current
Quies c ent Current
Ground P in Current
I
O
I
LI M
I
SC
I
Q
I
G N D
V
O
> 1.2V
V
O
> 1.2V
V
O
< 0.4V
I
O
= 0m A
I
O
= 1m A to 1.5A
I
O
= 1m A
V
IN
= V
O
+ 1 to V
O
+ 2
V
O
< 2.0V
4.0V > V
O
> = 2.0V
V o > = 4.0V
Load Regulation
Over Tem erature S hutdown
Over Tem erature Hy s teris is
V
O
Tem perature Coeffic ient
RE G
LO AD
OTS
OTH
TC
f= 1k Hz
P ower S upply Rejec tion
P S RR
I
O
= 100m A
C
O
= 4.7
µ
F
f= 10k Hz
f= 100k Hz
I
O
= 100m A
C
O
= 4.7
µ
F
f= 1k Hz
f= 10k Hz
f= 100k Hz
Co= 4.7
µ
F
Co= 100
µ
F
Co= 4.7
µ
F
Co= 100
µ
F
I
O
= 1m A to 1500m A
-0.15
-0.1
-0.4
0.02
0.2
0.2
150
30
30
50
20
15
75
55
30
30
20
30
20
1
1.223
V
IN
= 2.7V to 7V
V
IN
= 2.7V to 7V
V
EN
= V
IN
, V
IN
= 2.7V to 7V
V
EN
= V
O V
, V
IN
= 2.7V to 7V
V
I N
= 5V , V
O
= 0V , V
EN
< V
EL
Note1
Note1
V
PG
= 7V
V
O
in regulation
I
SI N K
= 500
µ
A
115
1
7
0.4
0.5
2.0
0
1.242
1.261
V in
0.4
0.1
0.5
1
85
m V rm s
dB
dB
1500
1500
2000
750
35
35
0.15
0.1
0.4
1
1500
50
S ee
c hart
Te st Condition
M in
Note 1
-1.5
Typ
Max
7
1.5
1000
800
600
mA
mA
mA
µ
A
µ
A
%
%
%
%
o
o
Units
V
%
Dropout V oltage
V
D R OPOU T
mV
Line Regulation
RE G
LIN E
C
C
ppm /
o
C
P ower S upply Rejec tion
P S RR
C
BY P
= 0.01
µ
F
f= 10Hz to 100k Hz
I
O
= 10m A ,C
BY P
= 0
µ
F
f= 10Hz to 100k Hz
I
O
= 10m A ,C
BY P
= 0.01
µ
F
Output V oltage Nois e
eN
Output V oltage Nois e
A DJ Input B ias Current
A DJ Referenc e V oltage
E N Input Thres hold
eN
I
AD J
V
R EF
V
EH
V
EL
I
EH
I
EL
I
SD
V
UV
V
OV
I
LC
V
PG
V
OL
m V rm s
mA
V
V
V
µ
A
µ
A
µ
A
% V
O (N O M)
% V
O (N O M)
mA
V
V
E N Input B ias Current
S hutdown S upply Current
Output Under V oltage
Output Over V oltage
P G Leak age Current
P G V oltage Rating
P G V oltage Low
Note1:V
IN (m in)
= V
O U T
+ V
D R O P O U T
4
Analog Microelectronics, Inc.
AME8817
NARY
RELIMI
P
1.5A CMOS LDO
n
Detailed Description
The AME8817 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 2.2A. During thermal shut-
down, the output voltage remains low. Normal operation
is restored when the junction temperature drops below
110
o
C.
The AME8817 behaves like a current source when the
load reaches 2.2A. However, if the load impedance
drops below 0.3 ohms, the current drops back to 600mA
to prevent excessive power dissipation. Normal op-
eration is restored when the load resistance exceeds
0.75 ohms.
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.
n
Enable
When 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 AME8817 includes the Power Good feature. Nor-
mally, the PG pin is "Floating", however, when the out-
put is not within
±15%
of the specified voltage, it pulls
low. This can occur under the following conditions:
1) Input Voltage too low.
2) During Over-Temperature.
3) During Over-Current.
4) If output is pulled up.
n
External Capacitors
The AME8817 is stable with an output capacitor to ground
of 4.7µF 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 0.1µF ceramic capacitor
with a 10µF 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 0.1µF to have a beneficial effect.
A third capacitor can be connected between the BY-
PASS pin and GND. This capacitor can be a low cost
Polyester Film variety between the value of 0.001 ~
0.01µF. A larger capacitor improves the AC ripple re-
jection, but also makes the output come up slowly. This
"Soft" turn-on is desirable in some applications to limit
turn-on surges.
5
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