LTC3526EDC Datasheet, PDF (1/16 Pages) Linear Technology – 500mA 1MHz Synchronous Step-Up DC/DC Converters in 2mm X 2mm DFN

NOT RECOMMENDED FOR NEW DESIGNS
Contact Linear Technology for Potential Replacement
LTC3526/LTC3526B
500mA 1MHz Synchronous
Step-Up DC/DC Converters
in 2mm × 2mm DFN
Features
n _{Delivers 3.3V at 100mA from a Single Alkaline/}
NiMH Cell or 3.3V at 200mA from Two Cells
n _{VIN Start-Up Voltage: 850mV}
n _{1.6V to 5.25V VOUT Range}
n _{Up to 94% Efficiency}
n _{Output Disconnect}
n _{1MHz Fixed Frequency Operation}
n _{VIN > VOUT Operation}
n _{Integrated Soft-Start}
n _{Current Mode Control with Internal Compensation}
n _{Automatic Burst Mode}^® _{Operation with 9µA}
Quiescent Current (LTC3526)
n _{Low Noise PWM Operation (LTC3526B)}
n _{Internal Synchronous Rectifier}
n _{Logic Controlled Shutdown (IQ < 1µA)}
n _{Anti-Ringing Control}
n _{Low Profile (2mm × 2mm × 0.75mm) DFN Package}
Applications
n _{Medical Instruments}
n _{Flash-Based MP3 Players}
n _{Noise Canceling Headphones}
n _{Wireless Mice}
n _{Bluetooth Headsets}
Description
The LTC^®3526/LTC3526B are synchronous, fixed frequency
step-up DC/DC converters with output disconnect. Syn-
chronous 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 1MHz 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 features automatic Burst Mode operation at light
load conditions, while the LTC3526B features continuous
switching at light loads. Anti-ringing control circuitry also
reduces EMI concerns by damping the inductor in discon-
tinuous mode. Additional features include a low shutdown
current of under 1µA and thermal shutdown.
The LTC3526/LTC3526B are housed in a 2mm × 2mm ×
0.75mm DFN package.
For new designs, we recommend the LTC3526L/LTC3526LB.
L, LT, LTC, LTM, Linear Technology, the Linear logo and Burst Mode are registered trademarks
and ThinSOT is a trademark of Linear Technology Corporation. All other trademarks are the
property of their respective owners.
Typical Application
4.7µH
V_IN
1.6V TO 3.2V
1µF
OFF ON
SW
V_IN
V_OUT
LTC3526
SHDN FB
GND
1.78M
V_OUT
3.3V
200mA
4.7µF
1M
3526 TA01a
LTC3526 Efficiency and Power Loss vs Load Current
100
V_IN = 2.4V
90
80
EFFICIENCY
1000
100
70
60
10
50
POWER LOSS
40
1
30
20
0.1
10
0
0.01
0.01
0.1
1
10 100 1000
LOAD CURRENT (mA)
3526 TA01b
3526bfd