LTC3526L-2_15 Datasheet, PDF (1/16 Pages) Linear Technology – 550mA 2MHz Synchronous Step-Up DC/DC Converters

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: 680mV}
n _{1.5V 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 IQ (LTC3526L-2)}
n _{Low Noise PWM Operation (LTC3526LB-2)}
n _{Internal Synchronous Rectifier}
n _{Logic Controlled Shutdown (IQ < 1µA)}
n _{Anti-Ring Control}
n _{Low Profile (2mm × 2mm × 0.75mm) 6-Lead}
DFN Package
Applications
n _{Medical Instruments}
n _{Noise Canceling Headphones}
n _{Wireless Mice}
n _{Bluetooth Headsets}
LTC3526L-2/LTC3526LB-2
550mA 2MHz Synchronous
Step-Up DC/DC Converters
in 2mm × 2mm DFN
Description
The LTC^®3526L-2/LTC3526LB-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
a 680mV 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 LTC3526L-2 features Burst Mode operation at light
load conditions allowing it to maintain high efficiency over
a wide range of load. The LTC3526LB-2 features fixed
frequency operation for low noise applications. Anti-ring
circuitry reduces EMI by damping the inductor in discon-
tinuous mode. Additional features include a low shutdown
current of under 1µA and thermal shutdown.
The LTC3526L-2/LTC3526LB-2 are housed in a 2mm ×
2mm × 0.75mm DFN package.
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
4.7µF
OFF ON
SW
V_IN
V_OUT
LTC3526L-2
SHDN FB
GND
1.78M
1M
33pF
V_OUT
3.3V
200mA
4.7µF
3526lb2 TA01a
Efficiency and Power Loss vs Load Current
100
V_IN = 2.4V
90
1000
80
EFFICIENCY
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)
3526lb2 TA01b
3526lb2fa