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IP Library: Ultra Low Nois e, High PSRR, Low Power,
20mA Low Dropout Volt age Regulator
■
RF REGULATOR
■
VERY LOW DROPOUT VOLTAGE : 60mV
■
ULTRA LOW OUTPUT VOLTAGE NOISE
■
HIGH PSRR : 70dB
■
LOW QUIESCENT CURRENT : 70µA FULL
LOAD
■
NO CURRENT IN POWER DOWN MODE
■
SHORT CIRCUIT PROTECTION
■
SMALL DECOUPLING CERAMIC CAPACIT OR
■
MOS INPUT STAG E
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 typical) with an
equivalent serial resistance (ESR) in the range
0.02 to 0.6Ω is used to ensure stability.
Figure 1 :
Block Diagram
?
V
REF
?
?
LDO_59
OUTIN
PWRDWN
Figure 2 :
Typical Application Circuit
1µF
ESR
V
OUT
C
OUT
?
?
OUT
GND
?
?
V
IN
IN
Power Dow n Mode
OFF
ON
LDO_59
PWRDWN
LDO_59
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 < T < 125°C, 0.8µF < C
OUT
< 1.2µF, 20mΩ < ESR < 0.6Ω, 100µA < I
LOAD
<20mA.
Typical case :
V
IN
= 4V, T = 25°C, I
OUT
= 10mA.
Notes: 1. Above characteristics are given for 3V 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
LOAD
20 mA
P
MOS
Output Resistance R
ON
0,6 Ω
Dropout Voltage ∆V
DO
∆V
OUT
= 50mV,
I
LOAD
= 20mA
60 mV
(Note 2) 170
Quiescent current I
Q
I
LOAD
= 100µA5070µA
I
LOAD
= 20mA 70 150 µA
Power down mode quiescent
current
I
QPRWDWN
Power down active 100 nA
Power Supply Rejection Ratio PSRR DC to 10KHz 55 70 dB
f < 100KHz 40 50
Load Regulation Ldr 6 9 mV
Line Regulation Lir I
LOAD
= 20mA,
V
OUT
= 2.8V
0,5 1 mV
Line Transient Lirt V
OUT
= 2.8V,
I
LOAD
= 20mA,
∆V
IN
= 300mV
t
RISE
= t
FALL
= 10µs
0,5 1 mV
Load Transient Ldtr V
OUT
= 2.8V
t
FALL
= t
RISE
= 10µs
0,3 1 mV
Recovery time 4 6 µs
Output Noise Voltage en V
OUT
= 2.8V
100Hz < f < 1KHz
160 200
1KHz < f < 100KHz 60
Output decoupling capacitor C
OUT
1 µF
Settling time (from power down
to active mode)
V
OUT
= 2.8V,
C
OUT
= 1.2µF
20 50 µs
Short Circuit Current Limit I
SHORT
200 mA
nV
Hz
----------- -
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100 1000 10000 100000
50
55
60
65
70
Frequen cy (Hz)
PSRR (dB)
TYPCIAL CHARACTERISTICS
Figure 5 :
Load transient (rising edge)
Figure 6 :
Load transient (falling edge)
Figure 7 :
Settling time
Figure 8 :
PSRR vs Frequency
(I
LOAD
= 20mA ; VINmin)
Figure 3 :
Line transient (rising edge)
Figure 4 :
Line transient (falling edge)
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