PQ60120EML04 Datasheet, PDF (11/14 Pages) SynQor Worldwide Headquarters – Eighth-brick DC/DC Converter

Technical Specification
APPLICATION CONSIDERATIONS
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
(www.synqor.com) which provides an understanding of why
this instability arises, and shows the preferred solution for cor-
recting it.
Application Circuits: Figure D provides a typical circuit dia-
gram which details the input filtering and voltage trimming.
Input Filtering and External Capacitance: Figure E pro-
vides 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 elec-
trolytic input capacitor. The recommended external input capac-
itance is specified in the “Input Characteristics” section. More
detailed information is available in the application note titled
“EMI Characteristics” on the SynQor website.
Input: 35-75 V
Output: 12 V
Current: 4 A
Package: Eighth-brick
Vin(+)
Vout(+)
Electrolytic
Vsense(+)
Vin
External
Input
Capacitor
47µF
ON/OFF
R_trim-up
Trim
or
Filter
Vsense(^_)
R_trim-down C_load
I_load
Vin(^_)
Vout(^_)
Figure D: Typical application circuit (negative logic unit, permanently enabled).
L
Vin(+)
C
Vin(^_)
Figure E: Internal Input Filter Diagram (component values listed on the specifications page).
Product # PQ60120EML04
Phone [phone]
www.synqor.com
Doc.# 005-2EM612E Rev. C
04/25/06
Page 11