cf48240qtc06nrs-g SynQor Worldwide Headquarters, cf48240qtc06nrs-g Datasheet - Page 14

• Manufacturer Part Number: cf48240qtc06nrs-g
• Description: Quarter-brick Dc-dc Converter
• Manufacturer: SynQor Worldwide Headquarters

Product # CF48xxxQTXxx
Input System Instability: This condition can occur because
any dc-dc converter appears incrementally as a negative
resistance load. A detailed application note titled “Input System
Instability” is available on the SynQor website which provides
an understanding of why this instability arises, and shows the
preferred solution for correcting it.
APPLICATION CONSIDERATIONS
Input Filtering and External Capacitance: Figure D provides
a diagram showing the internal input filter components. This filter
dramatically reduces input terminal ripple current, which otherwise
could exceed the rating of an external electrolytic input capacitor.
V
in
Figure D: Internal Input Filter Diagram
Phone [phone]
Figure C: Typical application circuit (negative logic unit, permanently enabled).
External
Input
Filter
V
Electrolytic
Capacitor
V
in(+)
in(
www.synqor.com
_
)
V
ON/OFF
V
in(+)
in(
(component values listed on the specifications page)
L
_
)
Application Circuits: Figure C provides a typical circuit diagram
which details the input filtering and voltage trimming.
The recommended external input capacitance is specified in the
Input Characteristics section on the Electrical Characteristics
page. More detailed information is available in the application note
titled “EMI Characteristics” on the SynQor website.
Doc.# 005-0005450 Rev. B
V
V
sense(+)
V
sense(
V
out(+)
out(
Trim
C
_
_
)
)
R
R
trim-up
trim-down
CF48xxxQTxxx
Specification
or
05/11/10
Technical
C
load
.
I
load
Page 14