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dc2358af
DEMO MANUAL DC2358A
DESCRIPTION
LTM8068
Isolated μModule DC/DC Converter
with LDO Regulator
The Demo Circuit 2358A is a 2kV AC isolated flyback
μModule
®
DC/DC converter with LDO post regulator featur-
ing the
LTM8068
. The demo circuit is designed for a 5.6V
flyback output and a 5V post regulator output from a 4.5V
to 40V input. The current capability of the 5.6V flyback
output varies with input voltage from about 200mA at
4.5V
IN
to about 460mA at 40V
IN
. The current capability of
the 5V LDO output is limited by either the current capabil-
ity of V
OUT1
minus V
OUT1
loading or the 300mA current
limit on the LDO post regulator itself. Figure 1 shows the
maximum output current on V
OUT1
when V
OUT2
is not
loaded, and V
OUT2
when V
OUT1
is unloaded. V
OUT2
is the
LDO post regulator from V
OUT1
.
L
, LT, LTC, LTM, Linear Technology, the Linear logo and µModule are registered trademarks of
Linear Technology Corporation. All other trademarks are the property of their respective owners.
The two-stage converter provides an isolated flyback output
as well as a low-noise LDO output. Figure 2 shows the
output noise spectrum on the flyback output and Figure
3 shows the output noise spectrum on the LDO output.
The LTM8068 data sheet gives complete description of
the device, operation and application information. The
data sheet must be read in conjunction with this quick
start guide for demo circuit 2358A.
Design files for this circuit board are available at
http://www.linear.com/demo/DC2358A
BOARD PHOTO
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