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IP Library: Ultra Low Nois e, Low power,
100mA Low Dropout Volt age Regulator
■
RF REGULATOR
■
VERY LOW DROPOUT VOLTAGE : 50mV
■
ULTRA LOW OUTPUT NOISE
■
HIGH OUTPUT CURRENT : 100mA
■
LOW QUIESCENT CURRENT : 110µA
■
HIGH PSRR : 65dB
■
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) in the range
0.02 to 0.6Ω is used for regulator stability.
Figure 1 :
Block Diagram
?
V
REF
?
?
?
LDO_58
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_58
→
→
Stand-by Mode
→
→
LDO_58
This is advance information on a new product now in development or undergoing evaluation. Details are subject to change without notice.
PRODUCT PREVIEW
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ELECTRICAL CHARACTERISTICS
3V < V
IN
< 5.5V, -30°C < TA < +85°C, V
REF
= 2.8V, C
OUT
= 1µF ±20%, 20mΩ < ESR < 0.6Ω,
I
LOAD
= 100mA.
Typical case :
V
IN
= 4V, T = 25°C, C
OUT
= 1µF.
Notes: 1. Above characteristics are given for 2.9V minimum input operating range voltage, but regulator
is operational with 2.7V 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
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
= 100µA5070µA
I
LOAD
= 100mA 110 250
Quiescent Current in stand-by
mode
I
STDBY
I
LOAD
= 100µA2040
Power down mode quiescent
current
I
QPDM
Power down active 100 nA
Power Supply Rejection Ratio PSRR DC 45 65 dB
f = 10KHz 45 60
f = 100KHz 35 45
Line Regulation Lir I
LOAD
= 100mA,
V
IN
= 3V to 5.5V
0,5 1 mV
Load Regulation Ldr I
LOAD
= 100µA - 100mA 25 40 mV
Line Transient Lirt ∆V
IN
= 300mV
t
RISE
= t
FALL
=10µs
0,5 1,5 mV
Load Transient Ldtr I
LOAD
= 100µA - 100mA in 10µs310mV
Output Noise Voltage en 100Hz 40 65
1KHz - 10KHz 30 40
en
RMS
BW : 10Hz to 100KHz 25 30 µV
RMS
Output decoupling Capacitor C
OUT
1 µF
Settling time From power down to active
mode
20 50 µs
Short Circuit Current Limit I
SHORT
200 mA
nV
Hz
----------- -
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1 10 100 1000 10000 100000 1000000
-65
-55
-45
-35
FREQUENCY (Hz)
PSRR (d B )
150mV
170mV
200mV
2V
TYPCIAL CHARACTERISTICS
Figure 7 :
PSRR vs Frequency for Various
Voltage Drop (I
LOAD
= 100mA)
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