1 A, Low Dropout,
CMOS Linear Regulator
ADP1706/ADP1707/ADP1708
FEATURES
TYPICAL APPLICATION CIRCUITS
Maximum output current: 1 A
Input voltage range: 2.5 V to 5.5 V
Low shutdown current: <1 μA
Low dropout voltage: 345 mV @ 1 A load
Initial accuracy: 1ꢀ
ADP1706
10nF
1
2
3
4
EN
SS
8
7
6
5
GND SENSE
V
= 3.3V
OUT
IN
IN
OUT
OUT
V
= 5V
IN
4.7µF
4.7µF
Accuracy over line, load, and temperature: 2.5ꢀ
16 fixed output voltage options with soft start:
0.75 V to 3.3 V (ADP1706)
Figure 1. ADP1706 with Fixed Output Voltage, 3.3 V
16 fixed output voltage options with tracking
0.75 V to 3.3 V (ADP1707)
Adjustable output voltage option:
ADP1707
V
1
2
3
4
EN
TRK
8
7
6
5
TRK
V
GND SENSE
0.8 V to 5.0 V (ADP1708)
IN
IN
OUT
OUT
OUT
V
= 5V
IN
Stable with small 4.7 μF ceramic output capacitor
Excellent load/line transient response
Current limit and thermal overload protection
Logic-controlled enable
Available in an 8-lead, exposed paddle SOIC and
3 mm × 3 mm, 8-lead exposed paddle LFCSP
4.7µF
4.7µF
V
(V)
OUT
3
2
1
0
1
2 3 4 5
TRK
V
(V)
APPLICATIONS
Figure 2. ADP1707 with Output Voltage Tracking
Notebook computers
Memory components
Telecommunications equipment
Network equipment
DSP/FPGA/microprocessor supplies
Instrumentation equipment/data acquisition systems
ADP1708
R2
R1
1
2
3
4
EN
ADJ
8
7
6
5
GND SENSE
V
= 0.8V(1 + R1/R2)
OUT
IN
IN
OUT
OUT
V
= 5V
IN
4.7µF
4.7µF
Figure 3. ADP1708 with Adjustable Output Voltage, 0.8 V to 5.0 V
GENERAL DESCRIPTION
ADP1707 and ADP1708 contain internal soft start capacitors
that give a typical start-up time of 100 μs. The ADP1707
includes a tracking feature that allows the output to follow an
external voltage rail or reference.
The ADP1706/ADP1707/ADP1708 are CMOS, low dropout
linear regulators that operate from 2.5 V to 5.5 V and provide
up to 1 A of output current. Using an advanced proprietary
architecture, they provide high power supply rejection and
achieve excellent line and load transient response with a small
4.7 μF ceramic output capacitor.
The ADP1706/ADP1707/ADP1708 are available in an 8-lead,
exposed paddle SOIC package and an 8-lead, 3 mm × 3 mm
exposed paddle LFCSP, making them not only very compact
solutions but also providing excellent thermal performance for
applications requiring up to 1 A of output current in a small,
low profile footprint.
The ADP1706/ADP1707 are available in 16 fixed output volt-
age options. The ADP1708 is available in an adjustable version,
which allows output voltages that range from 0.8 V to 5.0 V via
an external divider. The ADP1706 allows an external soft start
capacitor to be connected to program the start-up time; the
Rev. 0
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