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June 2002
s
ULTRA LOW POWER REGULATOR
s
ULTRA LOW CONSUMPTION : 45A FULL
LOAD
s
VERY LOW NOISE : 30V
s
VERY LOW DROPOUT VOLTAGE : 50mV
s
HIGH PSRR : 60dB
s
SMALL DECOUPLING CERAMIC CAPACITOR
s
NO CURRENT IN POWER DOWN MODE
s
SHORT CIRCUIT PROTECTION
TYPICAL APPLICATIONS
Cellular and Cordless phones supplied by 1 cell
Lithium-ion battery / 3 cells Ni-MH or Ni-Cd
battery
PDA (Personal Digital Assistant)
Smart phone
Portable equipment
Supply for RF devices for cellular phone
APPLICATION NOTE
An external capacitor (C
OUT
= 2.2F) with an
equivalent serial resistance (ESR) in the range of
0.02 to 0.6
is used for regulator stability.
Figure 1 : Block Diagram
?
V
REF
?
?
?
LDO_518
OUT
IN
PWRDWN
STDBY
Figure 2 : Typical Application Circuit
2.2
F
ESR
V
OUT
C
OUT
?
?
OUT
GND
?
?
?
V
IN
IN
PWRDWN
Power Down Mode
OFF
ON
Stand-by Mode
STDBY
Active Mode
LDO_518
Stand-by Mode
LDO_518
This is advance information on a new product now in development or undergoing evaluation. Details are subject to change without notice.
PRODUCT PREVIEW
IP Library: Low Noise, High PSRR
100mA Low Dropout Voltage Regulator
LDO_518
2/4
ELECTRICAL CHARACTERISTICS
2V < V
IN
< 5V, -55C < T
A
< +125C, C
OUT
= 2.2F 20%, 20 m
< ESR < 0.6
, I
LOAD
= 100mA.
Typical case : V
IN
= 4V, T = 25C, C
OUT
= 2.2F.
Notes: 1. Above characteristics are given for 3V minimum input operating range voltage, but regulator is
operational with 2.5V minimum input voltage.
2. All parameters are guaranteed with 170mV min Dropout voltage.
Parameter Symbol
Test
Condition
Min.
Typ.
Max.
Unit
Input Voltage Range (Note 1)
V
IN
2
5
V
Output Voltage
V
OUT
1.8
V
Output Voltage Accuracy
3
%
Output current
I
OUT
100
mA
Dropout Voltage
V
DO
V
OUT
= 50mV,
I
LOAD
= 100mA
50
mV
(Note 2)
170
Quiescent current
I
Q
I
LOAD
= 100A
25
A
I
LOAD
= 1mA
25
I
LOAD
= 10mA
30
I
LOAD
= 50mA
35
I
LOAD
=100mA
45
50
Power down mode quiescent
current
I
QPDM
Power down active
100
nA
Power Supply Rejection Ratio
PSRR
V
DO
= 170mV ;
f < 1KHz
45
50
dB
f < 10KHz
35
40
V
DO
= 500mV;
f < 100Hz
60
65
f < 1KHz
55
60
f < 10KHz
40
45
Line Regulation
L
IR
I
LOAD
= 100mA,
V
IN
= 2V to 5V
0.5
1
mV
Load Regulation
L
DR
I
LOAD
= 100A - 100mA
15
20
mV
Line Transient
L
IRT
V
IN
= 300mV
t
RISE
= t
FALL
= 10s
6
10
mV
Load Transient
L
DTR
I
LOAD
= 100A - 100mA
in 10s
7
50
mV
Output Noise Voltage
en
100Hz
140
1KHz
75
10KHz
70
en
RMS
BW : 100Hz to 100KHz
40
V
RMS
Settling time
I
LOAD
= 100mA
35
s
nV
Hz
------------
LDO_518
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ELECTRICAL CHARACTERISTICS
2V < V
IN
< 5V, -55C < T
A
< +125C, C
OUT
= 2.2F 20%, 0.02
< ESR < 0.6
, I
LOAD
= 100mA.
Typical case : V
IN
= 4V, Ambient temperature, I
LOAD
= 100mA.
TYPICAL CHARACTERISTICS
Parameter Symbol
Test
Condition
Min.
Typ.
Max.
Unit
Output decoupling Capacitor
C
OUT
2.2
F
Cout equivalent serial resistor
ESR
0.02
0.6
Short Circuit Current Limit
I
SHORT
200
400
800
mA
Settling Time
t
S
35
60
s
Figure 3 : PSRR vs Frequency for Various Dropout (V
OUT
=1.8V, Full Load)
1
10
100
1000
10000
100000
1000000
-70
-60
-50
-40
-30
FREQUENCY (Hz)
PS
R
R
(
d
B
)
Drop=170m V
Drop=250m V
Drop=500m V
Drop=1V
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Information furnished is believed to be accurate and reliable. However, STMicroelectronics assumes no responsibility for the
consequences of use of such information nor for any infringement of patents or other rights of third parties which may result from
its use. No license is granted by implication or otherwise under any patent or patent rights of STMicroelectronics. Specifications
mentioned in this publication are subject to change without notice. This publication supersedes and replaces all information
previously supplied. STMicroelectronics products are not authorized for use as critical components in life support devices or
systems without express written approval of STMicroelectronics.
The ST logo is a registered trademark of STMicroelectronics
2002 STMicroelectronics - All Rights Reserved
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LDO_518
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