LTC3528-2
1A, 2MHz Synchronous
Step-Up DC/DC Converter
in 2mm × 3mm DFN
FEATURES
DESCRIPTION
Delivers 3.3V at 200mA from a Single Alkaline/
NiMH Cell or 3.3V at 400mA from Two Cells
n V Start-Up Voltage: 700mV
IN
n 0.50V to 5.5V Input Range
n 1.6V to 5.25V V
OUT Range
n Up to 94% Efficiency
n Output Disconnect
n 2MHz Fixed Frequency Operation
n V > V
IN
OUT Operation
n Integrated Soft-Start
n Current Mode Control with Internal Compensation
n Burst Mode® Operation with 12µA Quiescent Current
n Internal Synchronous Rectifier
n Logic Controlled Shutdown: <1µA
n Anti-Ringing Control
n Low Profile (2mm × 3mm × 0.75mm) DFN Package
The LTC®3528-2 is a synchronous, fixed frequency step-up
DC/DC converter with output disconnect. High efficiency
synchronous rectification, in addition to a 700mV startup voltage and operation down to 500mV once started,
provides longer run-time for single or multiple cell batterypowered products.
n
APPLICATIONS
n
n
n
n
A switching frequency of 2MHz minimizes solution
footprint by allowing the use of tiny, low profile inductors and ceramic capacitors. The current mode PWM is
internally compensated, simplifying the design process.
The LTC3528-2 enters Burst Mode operation at light loads.
Anti-ringing circuitry reduces EMI by damping the inductor in discontinuous mode. Additional features include a
low shutdown current, open-drain power good output,
short-circuit protection and thermal overload protection.
The LTC3528-2 is offered in an 8-lead 2mm × 3mm ×
0.75mm DFN package.
L, LT, LTC, LTM, Burst Mode, Linear Technology and the Linear logo are registered trademarks
and ThinSOT is a trademark of Linear Technology Corporation. All other trademarks are the
property of their respective owners.
Medical Instruments
Noise Canceling Headphones
Wireless Mice
Bluetooth Headsets
TYPICAL APPLICATION
Efficiency and Power Loss
100
90
2.2µH
4.7µF
VOUT
LTC3528-2
PGOOD
OFF ON
SHDN
GND
499k
68pF
VOUT
3.3V
400mA
10µF
FB
287k
100
EFFICIENCY
70
10
60
50
40
1
POWER LOSS
30
0.1
20
35282 TA01a
POWER LOSS (mW)
SW
VIN
EFFICIENCY (%)
80
VIN
1.8V TO 3.2V
1000
VOUT = 3.3V
VIN = 2.4V
10
0
0.01
0.1
1
10
100
0.01
1000
LOAD CURRENT (mA)
35282 TA01b
35282fa
1
