1
dc1737af
DEMO MANUAL DC1737A
DESCRIPTION
LTC3863
Low I
Q
Inverting
DC/DC Converter
Demonstration circuit 1737A is a current-mode inverting
DC/DC converter featuring the
The board operates from an input range of 4.5V to 16V,
and provides a –5.2V, 1.7A output or a –12V, 1A output
(jumper selectable). It operates at 400kHz and may be
synchronized to an external clock. A soft-start feature
controls output voltage slew rate at start-up, reducing
current surge and voltage overshoot. Burst Mode
®
opera-
tion that improves efficiency at light loads can be enabled
with a jumper. A power good output signal is provided.
The demonstration board has options for larger MOSFET
and diode packages on the back of the board for higher
output current requirements.
L
, LT, LTC, LTM, Linear Technology, the Linear logo and Burst Mode are registered trademarks
of Linear Technology Corporation. All other trademarks are the property of their respective
owners.
PERFORMANCE SUMMARY
This board is suitable for a wide range of automotive,
telecom, industrial, and other applications. The LTC3863
is available in small 12-pin thermally enhanced MSOP and
DFN Packages. For other output requirements, see the
LTC3863 data sheet or contact the LTC factory.
Design files for this circuit board are available at
Specifications are at T
A
= 25°C
SYMBOL
PARAMETER
CONDITIONS
MIN
TYP
MAX
UNITS
V
IN
Input Supply Range
4.5
16
V
V
OUT
Output Voltage
–5.2V/–12V
V
I
OUT
Output Current Range, Continuous
Free Air
0
–1.7/1.0
A
f
SW
Switching (Clock) Frequency
400
kHz
V
OUT P-P
Output Ripple
V
IN
= 12V, V
OUT
= –12V, I
OUT
= 1A (20MHz BW)
30
mV
P-P
V
REG
Output Regulation
Line and Load (4.5V
IN
to 16V
IN
, –12V
OUT
, 0A to 1A Out)
±0.1
%
P
OUT
/P
IN
Efficiency (See Figure 3)
V
IN
= 12V, V
OUT
= –12V, I
OUT
= 1A
89.3
%
Approximate Size
Component Area
×
Top Component Height
0.9
×
0.8
×
0.18
Inches
