The devices offer a typical combination of low dropout
and low quiescent current expected of CMOS parts,
while uniquely providing the low noise and high ripple
rejection characteristics usually only associated with
bipolar LDO regulators.
The device has been optimized to meet the needs of
modern wireless communications design; Low noise,
low dropout, small size, high peak current, high noise
immunity.
The ILC7082 is designed to make use of low cost
ceramic capacitors while outperforming other devices
that require tantalum capacitors.
FEATURES
• Ultra low 1mV dropout per 1mA load
• 1% output voltage accuracy
• Only 30µVrms noise
• Uses low ESR ceramic output capacitor to minimise noise
and output ripple
• Only 100µA ground current at 100mA load
• Ripple rejection up to 85dB at 1kHz, 60dB at 1MHz
• Excellent line and load transient response
• Over current / over temperature protection
• Guaranteed to 150mA output current
• Industry standard five lead SOT-23 package
• Fixed 2.8V, 3.0V, 3.3V, 3.6V, 4.7V, 5.0V and adjustable
output voltage options
• Metal mask option available for custom voltages between
2.5V and 10V
APPLICATIONS
• Cellular phones
• Wireless communicators
• PDAs / palmtops / organizers
• Battery powered portable electronics
TYPICAL CIRCUIT
Ordering Information (T
A
= -40°C to +85°C)
V
OUT
C
OUT
V
IN
C
IN
1
5 SOT23-5 4
ILC7082AIM5-xx
ILC7082AIM5-ADJ
150mA, fixed voltage
150mA, adjustable voltage
ILC7082
2
3
C
NOISE
Note:
Fixed voltage options are defined by 2-digit code as shown in the
package markings information section of the data sheet.
ON
Patent Pending
OFF
Impala Linear Corporation
1
RF LDO
TM
is a trademark of Impala Linear Corporation
ILC7082 150mA Ultra Low Noise CMOS RF LDO
TM
Regulator
PIN DESCRIPTION ILC7082-xx ( fixed voltage version )
Pin Number
1
2
3
4
Pin Name
V
IN
GND
ON/OFF
C
NOISE
Connect directly to supply
Pin Description
Ground pin. Local ground for C
NOISE
and C
OUT
.
By applying less than 0.4V to this pin the device will be turned off.
Optional noise bypass capacitor may be connected between this pin and
GND (pin 2). Do not connect C
NOISE
directly to the main power ground plane.
5
V
OUT
Output Voltage. Connect C
OUT
between this pin and GND (pin 2).
PIN DESCRIPTION ILC7082-ADJ ( adjustable voltage version )
Pin Number
1
2
3
4
5
Pin Name
V
IN
GND
ON/OFF
V
ADJ
V
OUT
Connect directly to supply
Pin Description
Ground pin. Local ground for C
NOISE
and C
OUT
.
By applying less than 0.4V to this pin the device will be turned off.
Voltage feedback pin to set the adjustable output voltage. Do not connect a capacitor to
this pin.
Output Voltage. Connect C
OUT
between this pin and GND (pin 2).
PIN - PACKAGE CONFIGURATIONS
V
OUT
C
NOISE
V
OUT
V
ADJ
5 SOT23-5 4
5 SOT23-5 4
ILC7082-xx
1
2
3
ILC7082-ADJ
1
2
3
V
IN
GND ON
OFF
V
IN
GND ON
OFF
Fixed Voltage Option
Adjustable Voltage Option
Impala Linear Corporation
2
ILC7082 150mA Ultra Low Noise CMOS RF LDO
TM
Regulator
ABSOLUTE MAXIMUM RATINGS (NOTE 1)
Parameter
Input voltage
On/Off Input voltage
Output Current
Output voltage
Package Power Dissipation
(SOT-23-5)
Maximum Junction Temp Range
Storage Temperature
Operating Ambient Temperature
Package Thermal Resistance
T
J(max)
T
STG
T
A
θ
JA
Symbol
V
IN
V
ON/OFF
I
OUT
V
OUT
P
d
Ratings
-0.3 to +13.5
-0.3 to V
IN
Short circuit protected
-0.3 to V
IN
+0.3
250
( Internally Limited )
-40~+150
-40~+125
-40 to +85
333
Units
V
mA
V
mW
°C
°C
°C
°C/W
ELECTRICAL CHARACTERISTICS ILC7082AIM5
Unless otherwise specified, all limits are at T
A
=25°C; V
IN
= V
OUT(NOM)
+1V, I
OUT
= 1mA, C
OUT
= 1µF, V
ON/OFF
= 2V.
Boldface
limits apply over the operating temperature range.
(Note 2)
Parameter
Input Voltage Range
Symbol
V
IN
Conditions
Min
2
Typ
Max
13
Units
V
Iout = 1mA
1mA < I
OUT
< 100mA
1mA < I
OUT
< 100mA
1mA < I
OUT
< 150mA
1mA < I
OUT
< 150mA
Feedback Voltage
(ADJ version)
Line Regulation
V
ADJ
∆V
OUT
/
(V
OUT
*∆V
IN
)
-1
-1.5
-2.5
-2.5
-3.5
1.215
1.202
V
OUT(NOM)
V
OUT(NOM)
V
OUT(NOM)
1.240
0.007
+1
+1.5
+2.5
+2.5
+3.5
1.265
1.278
0.014
0.032
%/V
V
%Vout
(Nom)
Output Voltage
V
OUT
VOUT(NOM) +1V < V
IN
< 12V
I
OUT
= 0mA
(Note 4)
I
OUT
= 10mA
0.1
10
50
1
2
25
35
75
100
mV
Dropout Voltage
(Note 3)
V
IN
- V
OUT
I
OUT
= 50mA
I
OUT
= 100mA
I
OUT
= 150mA
100
150
150
200
225
300
Impala Linear Corporation
3
ILC7082 150mA Ultra Low Noise CMOS RF LDO
TM
Regulator
ELECTRICAL CHARACTERISTICS ILC7082AIM5 ( Continued )
Unless otherwise specified, all limits are at T
A
=25°C; V
IN
= V
OUT(NOM)
+1V, I
OUT
= 1mA, C
OUT
= 1µF, V
ON/OFF
= 2V.
Boldface
limits apply over the operating temperature range.
(Note 2)
Parameter
Symbol
Conditions
I
OUT
= 0mA
I
OUT
= 10mA
Min
Typ
95
100
100
Max
200
220
220
240
220
240
Units
Ground Pin Current
I
GND
I
OUT
= 50mA
I
OUT
= 100mA
I
OUT
= 150mA
µA
100
115
0.1
1.5
0.3
1
400
500
240
260
260
280
2
13
0.6
µA
V
Shutdown (OFF) Current
ON/OFF Input Voltage
ON/OFF Pin Input
Current
( Note 5 )
Peak Output Current
(Note 4)
Output Noise voltage
(RMS)
I
ON/OFF
V
ON/OFF
I
IN( ON/OFF)
V
ON/OFF
= 0V
High = Regulator On
Low = Regulator Off
V
ON/OFF
= 0.6V, regulator OFF
V
ON/OFF
= 2V, regulator ON
µA
mA
µVrms
I
OUT(peak)
V
OUT
> 0.95V
OUT(NOM)
,
t
pw
=2ms
e
N
BW=300Hz to 50kHz,C
IN
=1µF
C
NOISE
=0.01µF, C
OUT
=2.2µF,
I
OUT
=10mA
freq = 1kHz,
C
OUT
=4.7µF,
I
OUT
=100mA
30
85
70
60
dB
Ripple Rejection
∆V
OUT
/∆V
IN
freq = 10kHz,
freq = 1MHz,
Dynamic Line
Regulation
∆V
OUT(line)
V
IN
: V
OUT(NOM)
+1V
to V
OUT(NOM)
+2V,
tr/tf = 2µs; I
OUT
=150mA
14
mV
Dynamic Load
Regulation
Short Circuit Current
∆V
OUT(load)
I
SC
I
OUT
: 1mA to 150mA; t
r
< 5µS
V
OUT
= 0V
40
600
mV
mA
Note 1: Absolute maximum ratings indicate limits which when exceeded may result in damage to the component. Electrical specifications do not apply when operating
the device outside of its rated operating conditions.
Note 2: Specified Min/Max limits are production tested or guaranteed through correlation based on statistical control methods. Measurements are taken at constant
junction temperature as close to ambient as possible using low duty pulse testing.
Note3: Dropout voltage is defined as the input to output differential voltage at which the output voltage drops 2% below the nominal value measured with a 1V differential.
Note 4: Guaranteed by design
Note 5 :The device’s shutdown pin includes a 2MΩ internal pull down resistor connected to ground.
Impala Linear Corporation
4
ILC7082 150mA Ultra Low Noise CMOS RF LDO
TM
Regulator
OPERATION
The ILC7082 LDO design is based on an advanced
circuit configuration for which patent protection has
been applied. Typically it is very difficult to drive a
capacitive output with an amplifier. The output
capacitance produces a pole in the feedback path,
which upsets the carefully tailored dominant pole of the
internal amplifier. Traditionally the pole of the output
capacitor has been “eliminated” by reducing the output
impedance of the regulator such that the pole of the
output capacitor is moved well beyond the gain
bandwidth product of the regulator. In practice, this is
difficult to do and still maintain high frequency
operation. Typically the output impedance of the
regulator is not simply resistive, such that the reactive
output
impedance
interacts
with
the
reactive
impedance of the load resistance and capacitance. In
addition, it is necessary to place the dominant pole of
the circuit at a sufficiently low frequency such that the
gain of the regulator has fallen below unity before any
of the complex interactions between the output and the
load occur. The ILC7082 does not try to eliminate the
output pole, but incorporates it into the stability
scheme. The load and output capacitor forms a pole,
which rolls off the gain of the regulator below unity. In
order to do this the output impedance of the regulator
must be high, looking like a current source. The output
stage of the regulator becomes a transconductance
amplifier, which converts a voltage to a current with a
substantial output impedance. The circuit which drives
the transconductance amplifier is the error amplifier,
which compares the regulator output to the band gap
reference and produces an error voltage as the input to
the transconductance amplifier. The error amplifier has
a dominant pole at low frequency and a “zero” which
cancels out the effects of the pole. The zero allows the
regulator to have gain out to the frequency where the
output pole continues to reduce the gain to unity. The
configuration of the poles and zero are shown in figure
1. Instead of powering the critical circuits from the
unregulated input voltage, the CMOS RF LDO powers
the internal circuits such as the bandgap, the error
amplifier and most of the transconductance amplifier
from the boot strapped regulated output voltage of the
regulator. This technique offers extremely high ripple
rejection and excellent line transient response.
A block diagram
ILC7082 is shown
output isolation
amplifiers that
outlined above.
of the regulator circuit used in the
in figure 2, which shows the input-to-
and the cascaded sequence of
implement the pole-zero scheme
The ILC7082 is designed in a CMOS process with
some minor additions, which allow the circuit to be
used at input voltages up to 13V. The resulting circuit
exceeds the frequency response of traditional bipolar
circuits. The ILC7082 is very tolerant of output load
conditions with the inclusion of both short circuit and
thermal overload protection. The device has a very low
dropout voltage, typically a linear response of 1mV per
milliamp of load current, and none of the quasi-
saturation characteristics of a bipolar output devices.
All the good features of the frequency response and
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