LTC3526-2_15 Datasheet, PDF (1/16 Pages) Linear Technology – 500mA 2MHz Synchronous Step-Up DC/DC Converters

LTC3526-2/LTC3526B-2
NOT RECOMMENDED FOR NEW DESIGNS
Contact Linear Technology for Potential Replacement
500mA 2MHz Synchronous
Step-Up DC/DC Converters
in 2mm × 2mm DFN
Features
Description
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 _{VIN Operating Range: 0.5V to 5V}
n _{1.6V to 5.25V VOUT Range}
n _{Up to 94% Efficiency}
n _{Output Disconnect}
n _{2MHz Fixed Frequency Operation}
n _{VIN > VOUT Operation}
n _{Integrated Soft-Start}
n _{Current Mode Control with Internal Compensation}
n _{Burst Mode}^® _{Operation with 9µA Quiescent Current}
(LTC3526-2)
n _{Low Noise PWM Operation (LTC3526B-2)}
n _{Internal Synchronous Rectifier}
n _{Logic Controlled Shutdown (IQ < 1µA)}
n _{Anti-Ringing Control}
n _{Low Profile (2mm × 2mm × 0.75mm) DFN-6 Package}
Applications
n _{Medical Instruments}
n _{Flash-Based MP3 Players}
n _{Noise Canceling Headphones}
n _{Wireless Mice}
n _{Bluetooth Headsets}
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.
For new designs, we recommend the LTC3526L-2/
LTC3526LB-2.
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. Patents pending.
Typical Application
2.2µH
V_IN
1.6V TO 3.2V
1µF
OFF ON
SW
V_IN
V_OUT
LTC3526-2
SHDN FB
GND
1.78M
V_OUT
3.3V
200mA
4.7µF
1M
35262b2 TA01a
LTC3526-2 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)
35262b2 TA01b
35262b2fc