LTC3526-2/LTC3526B-2
500mA 2MHz Synchronous
Step-Up DC/DC Converters
in 2mm
×
2mm DFN
FEATURES
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DESCRIPTION
The LTC
®
3526-2/LTC3526B-2 are synchronous, fixed
frequency step-up DC/DC converters with output discon-
nect. Synchronous rectification enables high efficiency
in the low profile 2mm
×
2mm DFN package. Battery life
in single AA/AAA powered products is extended further
with an 850mV start-up voltage and operation down to
500mV once started.
A switching frequency of 2MHz minimizes solution foot-
print by allowing the use of tiny, low profile inductors
and ceramic capacitors. The current mode PWM design
is internally compensated, reducing external parts count.
The LTC3526-2 features Burst Mode operation at light load
conditions, while the LTC3526B-2 features continuous
switching. Anti-ring circuitry eliminates EMI concerns by
damping the inductor in discontinuous mode. Additional
features include a low shutdown current of under 1μA and
thermal shutdown.
The LTC3526-2/LTC3526B-2 are housed in a 6-pin
2mm
×
2mm
×
0.75mm DFN package.
L,
LT, LTC and LTM are registered trademarks of Linear Technology Corporation. Burst Mode
is a trademark of Linear Technology Corporation. All other trademarks are the property of their
respective owners. Patents pending.
Delivers 3.3V at 100mA from a Single Alkaline/
NiMH Cell or 3.3V at 200mA from Two Cells
V
IN
Start-Up Voltage: 850mV
V
IN
Operating Range: 0.5V to 5V
1.6V to 5.25V V
OUT
Range
Up to 94% Efficiency
Output Disconnect
2MHz Fixed Frequency Operation
V
IN
> V
OUT
Operation
Integrated Soft-Start
Current Mode Control with Internal Compensation
Burst Mode
®
Operation with 9μA Quiescent Current
(LTC3526-2)
Low Noise PWM Operation (LTC3526B-2)
Internal Synchronous Rectifier
Logic Controlled Shutdown (I
Q
< 1μA)
Anti-Ringing Control
Low Profile (2mm
×
2mm
×
0.75mm) DFN-6 Package
APPLICATIONS
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Medical Instruments
Flash-Based MP3 Players
Noise Canceling Headphones
Wireless Mice
Bluetooth Headsets
TYPICAL APPLICATION
2.2μH
SW
V
IN
1.6V TO 3.2V
1μF
OFF ON
V
IN
V
OUT
1.78M
4.7μF
1M
35262b2fA01a
LTC3526-2 Efficiency and Power Loss vs Load Current
100
90
80
EFFICIENCY (%)
V
IN
= 2.4V
EFFICIENCY
100
POWER LOSS (mW)
1000
V
OUT
3.3V
200mA
70
60
50
40
30
20
10
0
0.01
0.1
1
10
100
0.01
1000
35262b2f TA01b
10
POWER LOSS
LTC3526-2
SHDN
GND
FB
1
0.1
LOAD CURRENT (mA)
35262b2fa
1
LINER [ LINEAR TECHNOLOGY ]
