
1/4June 2002
■
AnyESR REGULATOR
■
VERY COMMON OUTPUT DECOUPLING
CERAMIC CAPACITOR
■
LOW CONSUMPTION : 250µA FULL LOAD
■
VERY LOW NOISE : 30µV
■
VERY LOW DROPOUT VOLTAGE : 50mV
■
HIGH PSRR : 60dB
■
STAN DBY AND POWER DOWN MODE
■
NO CURRENT IN POWER DOWN MODE
■
SHORT CIRCUIT PROTECTION
TYPICAL APPLICATIONS
– Cellular and Cordless phones suppli ed by 1 cell
Lithium-ion battery / 3 cells Ni-MH or Ni-Cd
battery
– PDA (Personal Digital Assistant),
– Smart phone
– Portable equipm ent
– Supply for RF devices for cellular phone
APPLICATION NOTE
An external capacitor (C
OUT
= 1µF) with an
equivalent serial resistance (ESR) up to 1Ω is
used for regulator stability.
Figure 1 :
Block Diagram
?
V
REF
?
?
?
LDO_517
OUTIN
PWRDWN
STDBY
Figure 2 :
Typical Application Circuit
1µF
ESR
V
OUT
C
OUT
?
?
OUT
GND
?
?
?
V
IN
IN
PWRDWN
Power Down Mode
OFF
ON
Stand-by Mode
STDBY
Active Mode
LDO_517
→
→
Stand-by Mode
→
→
LDO_517
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: Wide Range ESR Capacitor, Low Noise,
100mA Low Dropout Volt age Regulator

LDO_517
2/4
ELECTRICAL CHARACTERISTICS
3V < V
IN
< 5.5V, -30°C < TA < +125°C, C
OUT
= 1µF ±20%, ESR < 1Ω, I
LOAD
= 100mA.
Typical case : V
IN
= 4V, T = 25°C, C
OUT
= 1µF.
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.
3. Output Noise density reaches its maximum at 1MHz (300nV / typical).
Parameter Symbol Test Condition Min. Typ. Max. Unit
Input Voltage Range (Note 1) V
IN
3 5.5 V
Output Voltage V
OUT
2.8 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
= 100µA 50 65 µA
I
LOAD
= 100mA 250 450
Power down mode quiescent
current
I
QPDM
Power down active 100 nA
Power Supply Rejection Ratio PSRR DC ; Dropout = 170mV 45 55 dB
10KHz < f < 100KHz 45 55
DC ; Dropout = 200mV 55 60
10KHz < f < 100KHz 50 60
Line Regulation L
IR
I
LOAD
= 100mA,
VIN = 3V to 5.5V
515mV
Load Regulation L
DR
I
LOAD
= 100µA - 100mA 15 20 mV
Line Transient L
IRT
∆V
IN
= 300mV
t
RISE
= t
FALL
= 10µs
3mV
Load Transient L
DTR
I
LOAD
= 100µA - 100mA
in 10µs
3mV
Output Noise Voltage (Note 3) en 100Hz 80
1KHz - 10KHz 70
100KHz 85
en
RMS
BW : 100Hz to 100KHz 30 µV
RMS
Output decoupling Capacitor C
OUT
1µF
Settling time I
LOAD
= 100mA 20 µs
Short Circuit Current Limit I
SHORT
200 400 800 mA
nV
Hz
----------- -
Hz

LDO_517
3/4
ELECTRICAL CHARACTERISTICS : (STAND-BY MODE)
3V < V
IN
< 5.5V, -30°C < TA < +125°C, C
OUT
= 1µF ±20%, ESR < 1Ω, I
LOAD
= 500µA.
Typical case : V
IN
= 4V, Ambient temperature, I
LOAD
= 500µA.
TYPICAL CHARACTERISTICS
Parameter Symbol Test Condition Min. Typ. Max. Unit
Output current in stand-by
mode
I
OUTSTDBY
500 µA
Quiescent Current in
stand-by mode
I
STDBY
I
LOAD
= 500µA 15 20 µA
Power Supply Rejection Ratio
in stand-by mode
PSRR
STY
DC ; Dropout > 1V 65 dB
f = 10KHz 65
f = 100KHz 45
Line Regulation in stand-by
mode
L
IRSTBY
VIN = 3V to 5.5V 2 mV
Load Regulation in stand-by
mode
L
DRSTBY
I
LOAD
= 100µA - 500µA 1 mV
Figure 3 :
PSRR vs Dropout for Various Frequency (V
OUT
= 2.8V, Full Load)
0.1 1
-65
-60
-55
-50
DROPOUT VOL AT AGE (mV)
PSRR (dB)
F=100KHz
F=10KHz

4/4
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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 li cense is granted by implication or otherwise unde r any patent or patent rights of STMicroelectronics. Specifications
mentioned in this publication ar e subject to change without notice. This publication supersedes and replaces all information
previously supplied. S TMicroelectronics products are not authorized for use as critica l components in life suppo rt devices or
systems without express written approval of STMicroelectronics.
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LDO_517