1
dc1687af
DEMO MANUAL DC1687A
Description
LTC3115EDHD-1
40V, 2A Synchronous
Buck-Boost DC/DC Converter
Demonstration circuit 1687A features the LTC
®
3115-1, a
high voltage monolithic synchronous buck-boost converter.
The DC1687A demo board has two user selectable operat-
ing modes: Burst Mode
®
operation and forced continuous
operation (fixed frequency PWM) (JP1). There is also an
accurate programmable RUN pin which is used to enable
the converter (JP2).
The DC1687A operates with a 2.7V to 40V input volt-
age range. The demo board has been designed with the
output voltage set to 5.0V. The LTC3115-1 incorporates a
proprietary low noise switching algorithm which optimizes
efficiency with input voltages above, below or equal to the
output voltage and ensures seamless transitions between
operating modes.
The demo board has been programmed to operate at 1MHz
in PWM mode to optimize small size with high efficiency
operation.
L
, LT, LTC, LTM, µModule, Burst Mode, Linear Technology and the Linear logo are registered
trademarks of Linear Technology Corporation. All other trademarks are the property of their
respective owners.
performance summary
The demo board also has optional provisions to back
feed V
CC
in order to increase efficiency in some 5V out-
put applications. There is also a provision for an optional
Schottky diode from SW2 to V
OUT
for applications where
V
OUT
is greater than 20V and short circuit protection is
desired. Consult the data sheet for more information on
these options.
Figures 1 and 2 show typical demo board efficiency.
The LTC3115-1 data sheet has detailed information about
the operation, specifications, and applications of the part.
The data sheet should be read in conjunction with this
quick start guide.
Design files for this circuit board are available at
http://www.linear.com/demo
PARAMETER
VALUE
Input Voltage Range
2.7V to 40V
V
OUT
5.0V
I
OUT
(See Note 1)
1A For V
IN
≥ 3.6V,
2A For V
IN
> 6V
Efficiency
See Figures 1 and 2
Note 1: The Demo Board output current is a function of V
IN
. Please refer to the data sheet for more information
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