LTC3025
300mA Micropower
VLDO Linear Regulator
FEATURES DESCRIPTION
TM
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Wide Input Voltage Range: 0.9V to 5.5V
The LTC 3025 is a micropower, VLDO (very low drop-
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Stable with Ceramic Capacitors
out) linear regulator which operates from input voltages as
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Very Low Dropout: 45mV at 300mA
low as 0.9V. The device is capable of supplying 300mA of
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Adjustable Output Range: 0.4V to 3.6V
output current with a typical dropout voltage of only 45mV.
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2% Voltage Accuracy over Temperature
A BIAS supply is required to run the internal reference and
Supply Load
LDO circuitry while output current comes directly from
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Low Noise: 80V (10Hz to 100kHz)
the IN supply for high ef ciency regulation. The low 0.4V
RMS
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BIAS Voltage Range: 2.5V to 5.5V
internal reference voltage allows the LTC3025 output to
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Fast Transient Recovery
be programmed to much lower voltages than available in
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Shutdown Disconnects Load from V and V
common LDOs (range of 0.4V to 3.6V). The output voltage
IN BIAS
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Low Operating Current: I = 4A, I = 50A Typ
is programmed via two ultrasmall SMD resistors.
IN BIAS
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Low Shutdown Current: I = 1A, I = 0.01A Typ
IN BIAS
The LTC3025s low quiescent current makes it an ideal
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Output Current Limit
choice for use in battery-powered systems. For 3-cell
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Thermal Overload Protection
NiMH and single cell Li-Ion applications, the BIAS voltage
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Available in 6-Lead (2mm 2mm) DFN Package
can be supplied directly from the battery while the input
can come from a high ef ciency buck regulator, providing
APPLICATIONS
a high ef ciency, low noise output.
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Low Power Handheld Devices
Other features include high output voltage accuracy,
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Low Voltage Logic Supplies
excellent transient response, stability with ultralow ESR
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DSP Power Supplies
ceramic capacitors as small as 1F, short-circuit and
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Cellular Phones
thermal overload protection and output current limiting.
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Portable Electronic Equipment
The LTC3025 is available in a tiny, low pro le (0.75mm)
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Handheld Medical Instruments
6-lead DFN (2mm 2mm) package.
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Post Regulator for Switching Supply Noise Rejection
L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and VLDO
and ThinSOT are trademarks of Linear Technology Corporation. All other trademarks are the
property of their respective owners.
TYPICAL APPLICATION
1.2V Output Voltage from 1.5V Input Supply 1MHz V Supply Rejection
IN
50
V = 1.2V
OUT
BIAS OUT
45
I 300mA C = 10F
OUT
OUT
0.1F 1F
Li-Ion
1.5V HIGH
LTC3025 80.6k
40
OR EFFICIENCY
1.5V
3-CELL DC/DC IN ADJ
35 C = 1F
OUT
NiMH BUCK
0.1F
30
40.2k
25
OFF ON SHDN GND
3025 TA01 20
15
10
BIAS = 3.6V I = 100mA
5 OUT
V = 1.2V I = 300mA
OUT OUT
0
2.0 2.6
1.2 1.4 1.6 1.8 2.2 2.4
V (V)
IN
3025fd
3025 TA01b
1
REJECTION (dB)LTC3025
ABSOLUTE MAXIMUM RATINGS PIN CONFIGURATION
(Notes 1, 2)
TOP VIEW
V , V to GND ......................................... 0.3V to 6V
BIAS IN
SHDN to GND ............................................... 0.3V to 6V
BIAS 1 6 SHDN
ADJ to GND .................................................. 0.3V to 6V
2 7
GND 5 ADJ
V ........................................0.3V to V + 0.3V or 6V
OUT IN
IN 3 4 OUT
Operating Junction Temperature Range
(Note 3) .................................................. 40C to 125C
DC6 PACKAGE
6-LEAD (2mm s 2mm) PLASTIC DFN
Storage Temperature Range ................... 65C to 125C
T = 125C, = 102C/W, = 20C/W
JMAX JA JC
Output Short-Circuit Duration .......................... Inde nite
EXPOSED PAD (PIN 7) IS GND, MUST BE SOLDERED TO PCB
ORDER INFORMATION
LEAD FREE FINISH TAPE AND REEL PART MARKING* PACKAGE DESCRIPTION TEMPERATURE RANGE
LTC3025EDC#PBF LTC3025EDC#TRPBF LBDY 6-Lead (2mm 2mm) Plastic DFN 40C to 125C
LTC3025IDC#PBF LTC3025IDC#TRPBF LBDY 40C to 125C
6-Lead (2mm 2mm) Plastic DFN
LEAD BASED FINISH TAPE AND REEL PART MARKING* PACKAGE DESCRIPTION TEMPERATURE RANGE
LTC3025EDC LTC3025EDC#TR LBDY 6-Lead (2mm 2mm) Plastic DFN 40C to 125C
LTC3025IDC LTC3025IDC#TR LBDY 6-Lead (2mm 2mm) Plastic DFN 40C to 125C
Consult LTC Marketing for parts speci ed with wider operating temperature ranges. *The temperature grade is identi ed by a label on the shipping container.
For more information on lead free part marking, go to: