Linear Technology DC1227A - LTC3534EDHC Demo board | 5V, 500mA Synchronous Buck-Boost DC/DC Converter DC1227A DC1227A Fiche De Données
Codes de produits
DC1227A
LTC3534
1
3534fb
Typical applicaTion
FeaTures
applicaTions
DescripTion
7V, 500mA Synchronous
Buck-Boost DC/DC
Converter
The
IN
range, highly efficient, fixed
frequency, buck-boost DC/DC converter that operates
from input voltages above, below or equal to the output
voltage. The topology incorporated in the IC provides a
continuous transfer function through all operating modes,
making the product ideal for multi-cell Alkaline/NiMH or
single Lithium-Ion/Polymer applications where the output
voltage is within the battery voltage range.
The LTC3534 offers extended V
The LTC3534 offers extended V
IN
and V
OUT
ranges of 2.4V
to 7V and 1.8V to 7V, respectively. Quiescent current is
only 25µA in Burst Mode operation, maximizing battery
life in portable applications. Burst Mode operation is user
controlled and can be enabled by driving the PWM pin
low. If the PWM pin is driven high then fixed frequency
switching is enabled.
Other features include fixed 1MHz operating frequency, a
Other features include fixed 1MHz operating frequency, a
<1µA shutdown, short-circuit protection, programmable
soft-start, current limit and thermal overload protection.
The LTC3534 is available in the thermally enhanced 16-lead
(3mm
× 5mm) DFN and 16-lead GN packages.
4 AA Cells to 5V at 500mA Buck-Boost Converter
n
Regulated Output with Input Voltages Above,
Below or Equal to the Output
n
2.4V to 7V V
IN
and 1.8V to 7V V
OUT
Ranges
n
5V V
OUT
at 500mA from 4 AA Cells
n
Single Inductor
n
Synchronous Rectification: Up to 94% Efficiency
n
Burst Mode
®
Operation with 25µA I
Q
n
Output Disconnect in Shutdown
n
1MHz Switching Frequency
n
<1µA Shutdown Current
n
Small Thermally Enhanced 16-Lead (5mm
× 3mm ×
0.75mm) DFN and 16-Lead GN Packages
n
Medical Instruments
n
Portable Barcode Readers
n
Portable Inventory Terminals
n
USB to 5V Supply
n
Handheld GPS
L
, LT, LTC and LTM are registered trademarks of Linear Technology Corporation.
Burst Mode is a registered trademark of Linear Technology Corporation.
All other trademarks are the property of their respective owners.
+
SW1
10k
15k
162k
649k
3534 TA01a
33pF
330pF
22µF
V
OUT
5V
500mA
SW2
PGND2
PGND1 GND
PV
IN
V
IN
PWM
RUN/SS
BURST PWM
OFF ON
V
OUT
FB
V
C
5µH
LTC3534
10µF
4 AA
CELLS
V
IN
3.6V TO 6.4V
V
IN
(V)
3.6
EFFICIENCY (%)
100
90
95
85
80
75
6.0
3534 TA01b
4.4
4.0
4.8
5.6
6.4
5.2
PWM I
OUT
= 500mA
PWM I
OUT
= 300mA
4 AA Cells to 5V Efficiency vs V
IN