1
Features
Low-noise Low Drop Out Voltage Regulator
2.8V Fixed Output Voltage
3V to 5.5V Supply Operation
130 mA Maximum Load Current
Power-down Mode Consumption Less Than 1 A
More Than 70 dB (Typical) PSRR at 1 kHz
29 V
RMS
Output Noise
0.35 m CMOS Technology
Typical Application: Radio Section Supply in Mobile Terminals
Description
RE027 is a Low Drop Out (LDO) voltage regulator macrocell with a fixed 2.8V output
voltage, rated for loads up to 130 mA. It is designed to be integrated with other analog
cells, digital logic, microcontrollers, DSP cores and memory blocks into system-on-
chip products.
The circuit consists of a PMOS pass device, an error amplifier and a feedback resis-
tive network, sized to achieve the required closed loop gain. These blocks make up
the regulating loop. An over-current and short circuit protection circuit has been
included to limit the output current delivered by the regulator, thus avoiding destruction
in case of a short circuit.
An external reference voltage (bandgap voltage) is necessary for correct functionality.
The target reference voltage is 1.231V delivered, for example, by BG019. Double pads
on the supply voltage V
BAT3B
/V
BAT3BB
and output voltage V
CRADIOA
/V
CRADIOAA
are used
to reduce the total output resistance. Current reference is generated inside the cell
through a circuit supplied by a 2.5V 0.1V regulated input voltage on V
SAUVC
. Remote
sense terminal V
CRADIOS
provides regulation at the load by connecting it to the output
terminal near a critical point to improve performance of the regulator (e.g., connecting
them at the package pin by double-bonding, thus avoiding the bonding resistance
influence). A capacitor of 2.2 F connected from V
CRADIOA
/V
CRADIOAA
to ground is
needed as external compensation.
Figure 1. Symbol
(1)
Note:
1. Pin names are written as they appear on the user screen when the symbol is
opened in the design tool environment.
vsauvc
vbg
on6
vcradioc
vbat3b
vbat3bb
vcradioa
vcradioaa
vcradios
gnd3
Embedded ASIC
Macrocell:
Power
Management for
Mobile
Terminals (PM)
RE027
Fixed 2.8V
130 mA
Low-noise LDO
Voltage
Regulator
Rev. 2701B-PMGMT02/03
3
RE027 2.8V 130 mA LDO Voltage Regulator
2701BPMGMT02/03
Absolute Maximum Ratings
*
Electrical Specifications
(1)
T
J
= -20
C to 125
C, V
BAT3B
/V
BAT3BB
= 3V to 5.5V unless otherwise specified, output capacitance = 2.2 F.
V
IN
.......................................................... -0.3V to 6.5V
*NOTICE:
Stresses beyond those listed under "Absolute Maxi-
mum Ratings" may cause permanent damage to the
device. This is a stress rating only and functional
operation of the device at these or other conditions
beyond those indicated in the operational sections of
this specification is not implied. Exposure to absolute
maximum rating conditions for extended periods may
affect device reliability.
Digital Signals......................................... -0.3V to 5.5V
Output Current..................................Internally Limited
Junction Temperature ..........................-40
C to 150
C
Table 1. Electrical Characteristics
Symbol
Parameter
Condition
Min
Typ
Max
Unit
V
BAT3B
/V
BAT3BB
Operating Supply Voltage
3
5.5
V
V
SAUVC
Auxiliary Operating Supply
Voltage
2.4
2.5
2.6
V
T
J
Junction Temperature Range
-20
125
C
V
CRADIOA
/
V
CRADIOAA
Output Voltage
2.75
2.8
2.85
V
I
CRADIOA
/
I
CRADIOAA
Output Current
130
mA
I
QQ
Quiescent Current
195
236
A
V
DC
Line Regulation
I
CRADIOA
/I
CRADIOAA
= 130 mA
2
3
mV
V
TRAN
Transient Line Regulation
I
CRADIOA
/I
CRADIOAA
= 130 mA
rise time = fall time = 5 s
2
3
mV
V
DC
Load Regulation
10% - 90% of max I
CRADIOA
/I
CRADIOAA
;
V
BAT3B
/V
BAT3BB
= 5.5V
2
3
mV
V
TRAN
Transient Load Regulation
10% - 90% of max I
CRADIOA
/I
CRADIOAA
;
rise time = fall time = 5 s
2
3
mV
PSRR
Power Supply Rejection Ratio
at Full Load
V
BAT
= 3V
@100 Hz
-75
dB
@1 kHz
-75
dB
@20 kHz
-50
dB
@100 kHz
-40
dB
V
BAT
= 4.25V
@100 Hz
-75
dB
@1 kHz
-75
dB
@20 kHz
-70
dB
@100 kHz
-55
dB
V
BAT
= 5.5V
@100 Hz
-75
dB
@1 kHz
-75
dB
@20 kHz
-70
dB
@100 kHz
-55
dB
4
RE027 2.8V 130 mA LDO Voltage Regulator
2701BPMGMT02/03
Notes:
1. Obtained by considering the parasitics of a TFBGA100 Package.
2. Obtained by using BG019 as reference voltage generator.
V
N
Output Noise
(2)
Bandwidth = 10 Hz to 100 kHz;
output current = 130 mA
29
37
V
RMS
T
R
Rise Time
100% of I
CRADIOA
/I
CRADIOAA
;
10% - 90% of V
CRADIOA
/V
CRADIOAA
50
s
I
SD
Shut Down Current
1
A
I
CC
Short-circuit Current Threshold
460
mA
Table 1. Electrical Characteristics (Continued)
Symbol
Parameter
Condition
Min
Typ
Max
Unit
5
RE027 2.8V 130 mA LDO Voltage Regulator
2701BPMGMT02/03
Control Modes
All digital signals are referred to the supply voltage V
BAT3B/BAT3BB
.
Application
Example
A ceramic capacitor of 2.2 F with ESR between 20 m
and 250 m
connected from
V
CRADIOA
/V
CRADIOAA
to ground is needed for external compensation.
Figure 3. Application Example
Table 2. Truth Table
ON6
V
CRADIOA
/V
CRADIOAA
0
Power down (High-Z)
1
Power on, V
CRADIOA
/V
CRADIOAA
= 2.8V
Description
Min
Typ
Max
Units
Capacitor (C
L
)
1.8
2.2
2.6
F
Digital
Core
1.231V Bandgap
(e.g., BG019)
2.5V
2.5V Regulator
(e.g., RE031)
V
BAT3B
V
BAT3BB
V
CRADIOA
V
CRADIOAA
V
CRADIOS
V
SAUVC
V
BG
ON6
V
CRADIOC
Battery
Pack
GND3
C
L
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