Product # PQ60280HEA13
Phone 1-888-567-9596
Doc.# 005-2HE628P Rev. A
04/17/06
Page 12
T
Technical S
echnical Specification
pecification
Input:
Output:
Current:
PPackage:
ackage:
35-75 V
28 V
12.8 A
Half-brick
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
provides an understanding of why this instability arises, and
shows the preferred solution for correcting it.
Application Circuits: Figure D below provides a typical cir-
cuit diagram which details the input filtering and voltage trim-
ming.
Input Filtering and External Input Capacitance: Figure E
below shows the internal input filter components. This filter dra-
matically reduces input terminal ripple current, which otherwise
could exceed the rating of an external electrolytic input capaci-
tor. The recommended external input capacitance is specified in
page. More detailed information is available in the application
Output Filtering and External Output Capacitance:
Figure E below shows the internal output filter components. This
filter dramatically reduces output voltage ripple. However, some
minimum external output capacitance is required, as specified in
page. No damage will occur without this capacitor connected,
but peak output voltage ripple will be much higher.
RoHS Compliance: The EU led RoHS (Restriction of Hazardous
Substances) Directive bans the use of Lead, Cadmium,
Hexavalent Chromium, Mercury, Polybrominated Biphenyls
(PBB), and Polybrominated Diphenyl Ether (PBDE) in Electrical
and Electronic Equipment. This SynQor product is available as
5/6 RoHS compliant (product with lead) or 6/6 RoHS compliant.
For more information please refer to SynQor’s RoHS addendum
Vin
External
Input
Filter
Trim
Vin(+)
Iload
Cload
C1
Cout
Lin
Lout/2
C2
Vout(+)
Rtrim-up
or
Rtrim-down
Vsense(+)
ON/OFF
Regulation
Stage
Isolation
Stage
Current
Sense
Vin(_)
Vin(+)
Vin(_)
Vout(+)
Vout(_)
Vsense(_)
Electrolytic
Capacitor
100F
ESR
0.2
2 x 4.7F
local ceramic
Figure D: Typical application circuit (negative logic unit, permanently enabled).
Figure E: Internal Input and Output Filter Diagram (component values listed on specifications page).