Datenblatt-Suchmaschine für elektronische Bauteile
  German  ▼
ALLDATASHEETDE.COM

X  

ADDC02828SA Datenblatt(PDF) 10 Page - Analog Devices

Teilenummer ADDC02828SA
Bauteilbeschribung  28 V/100 W DC/DC Converter with Integral EMI Filter
Download  16 Pages
Scroll/Zoom Zoom In 100%  Zoom Out
Hersteller  AD [Analog Devices]
Direct Link  http://www.analog.com
Logo AD - Analog Devices

ADDC02828SA Datenblatt(HTML) 10 Page - Analog Devices

Back Button ADDC02828SA Datasheet HTML 6Page - Analog Devices ADDC02828SA Datasheet HTML 7Page - Analog Devices ADDC02828SA Datasheet HTML 8Page - Analog Devices ADDC02828SA Datasheet HTML 9Page - Analog Devices ADDC02828SA Datasheet HTML 10Page - Analog Devices ADDC02828SA Datasheet HTML 11Page - Analog Devices ADDC02828SA Datasheet HTML 12Page - Analog Devices ADDC02828SA Datasheet HTML 13Page - Analog Devices ADDC02828SA Datasheet HTML 14Page - Analog Devices Next Button
Zoom Inzoom in Zoom Outzoom out
 10 / 16 page
background image
ADDC02828SA
REV. 0
–10–
The duration of this connection is 10
µs. The pulse is repeated
every second for 30 minutes. This test is repeated with the
connection of the 20
µF capacitor reversed to create a negative
pulse on the supply leads. (If continuous reverse voltage protec-
tion is required, a diode can be added externally in series at the
expense of lower efficiency for the power system.)
The converter responds to this input transient voltage test by
shutting down due to its input overvoltage protection feature.
Once the pulse is over, the converter initiates a soft-start, which
is completed before the next pulse. No degradation of converter
performance occurs.
THERMAL CHARACTERISTICS
Junction and Case Temperatures: It is important for the
user to know how hot the hottest semiconductor junctions
within the converter get and to understand the relationship
between junction, case and ambient temperatures. The hottest
semiconductors in the 100 W product line of Analog Devices’
high density power supplies are the switching MOSFETs and
the output rectifiers. There is an area inside the main power
transformers that is hotter than these semiconductors, but it is
within NAVMAT guidelines and well below the Curie tempera-
ture of the ferrite. (The Curie temperature is the point at which
the ferrite begins to lose its magnetic properties.)
Since NAVMAT guidelines require that the maximum junction
temperature be 110
°C, the power supply manufacturer must
specify the temperature rise above the case for the hottest semi-
conductors so the user can determine what case temperature
is required to meet NAVMAT guidelines. The thermal charac-
teristics section of the specification table states the hottest junction
temperature for maximum output power at a specified case
temperature. The unit can operate to higher case temperatures
than 90
°C, but 90°C is the maximum temperature that permits
NAVMAT guidelines to be met.
Case and Ambient Temperatures: It is the user’s responsibility
to properly heat sink the power supply in order to maintain the
appropriate case temperature and, in turn, the maximum junction
temperature. Maintaining the appropriate case temperature is a
function of the ambient temperature and the mechanical heat
removal system. The static relationship of these variables is
established by the following formula:
T
C = T A + ( P D × R
θ
CA
)
where
TC
= case temperature measured at the center of the pack-
age bottom,
TA
= ambient temperature of the air available for cooling,
PD
= the power, in watts, dissipated in the power supply,
Rθ
CA
= the thermal resistance from the center of the package
to free air, or case to ambient.
The power dissipated in the power supply, PD, can be calcu-
lated from the efficiency, , given in the data sheets and the
actual output power, PO, in the user’s application by the follow-
ing formula:
P
D = PO
1
η –1


For example, at 80 W of output power and 80% efficiency, the
power dissipated in the power supply is 20 W. If, under these
conditions, the user wants to maintain NAVMAT deratings
(i.e., a case temperature of approximately 90
°C) with an ambi-
ent temperature of 75
°C, the required thermal resistance, case
to ambient, can be calculated as
90 = 75 + (20
× Rθ
CA
) or Rθ
CA
= 0.75
°C/W
This thermal resistance, case to ambient, will determine what
kind of heat sink and whether convection cooling or forced air
cooling is required to meet the constraints of the system.
SYSTEM INSTABILITY CONSIDERATIONS
In a distributed power supply architecture, a power source
provides power to many “point-of-load” (POL) converters. At
low frequencies, the POL converters appear incrementally as
negative resistance loads. This negative resistance could cause
system instability problems.
Incremental Negative Resistance: A POL converter is de-
signed to hold its output voltage constant no matter how its
input voltage varies. Given a constant load current, the power
drawn from the input bus is therefore also a constant. If the
input voltage increases by some factor, the input current must
decrease by the same factor to keep the power level constant.
In incremental terms, a positive incremental change in the
input voltage results in a negative incremental change in the
input current. The POL converter therefore looks, incremen-
tally, as a negative resistor.
The value of this negative resistor at a particular operating
point, VIN, IIN, is:
R
N =
–V
IN
I
IN
Note that this resistance is a function of the operating point. At
full load and low input line, the resistance is its smallest, while
at light load and high input line, it is its largest.
Potential System Instability: The preceding analysis assumes
dc voltages and currents. For ac waveforms the incremental
input model for the POL converter must also include the effects
of its input filter and control loop dynamics. When the POL
converter is connected to a power source, modeled as a voltage
source, VS, in series with an inductor, LS, and some positive
resistor, RS, the network of Figure 23 results.
LP
CP
–|RN|
ADI DC/DC CONVERTER
LS
RS
VS
INPUT
TERMINALS
Figure 23. Model of Power Source and POL Converter
Connection
The network shown in Figure 23 is second order and has the
following characteristic equation:
s
2(L
S + LP )C + s
(L
S + LP )
–|RN|
+ R
SCP


+1 = 0


Ähnliche Teilenummer - ADDC02828SA

HerstellerTeilenummerDatenblattBauteilbeschribung
logo
Analog Devices
ADDC02828SA AD-ADDC02828SA_15 Datasheet
183Kb / 16P
   28 V/100 W DC/DC Converter with Integral EMI Filter
REV. 0
More results

Ähnliche Beschreibung - ADDC02828SA

HerstellerTeilenummerDatenblattBauteilbeschribung
logo
Analog Devices
ADDC02805S AD-ADDC02805S_15 Datasheet
186Kb / 16P
   28 V/100 W DC/DC Converter with Integral EMI Filter
REV. A
ADDC02828SA AD-ADDC02828SA_15 Datasheet
183Kb / 16P
   28 V/100 W DC/DC Converter with Integral EMI Filter
REV. 0
ADDC02812DA AD-ADDC02812DA_15 Datasheet
191Kb / 20P
   28 V/100 W DC/DC Converters with Integral EMI Filter
REV. 0
ADDC02815DA AD-ADDC02815DA_15 Datasheet
191Kb / 20P
   28 V/100 W DC/DC Converters with Integral EMI Filter
REV. 0
ADDC02812DA AD-ADDC02812DA Datasheet
259Kb / 20P
   28 V/100 W DC/DC Converters with Integral EMI Filter
REV. A
ADDC02803SC AD-ADDC02803SC Datasheet
241Kb / 18P
   28 V/66 W/100 W DC/DC Converters with Integral EMI Filter
REV. A
ADDC02803SC AD-ADDC02803SC_15 Datasheet
6Mb / 18P
   28 V 66 W 100 W DC/DC CONVERTERS WITH INTEGRAL EMI FILTER
REV. A
ADDC02808PB AD-ADDC02808PB_15 Datasheet
471Kb / 20P
   28 V, 200 W Pulsed DC/DC Converter with Integral EMI Filter
REV. 0
ADDC02808PB AD-ADDC02808PB Datasheet
287Kb / 20P
   28 V, 200 W Pulsed DC/DC Converter with Integral EMI Filter
REV. A
logo
Delta Electronics, Inc.
DVETR2800D DELTA-DVETR2800D Datasheet
275Kb / 15P
   HIGH RELIABILITY HYBRID DC-DC CONVERTERS WITH INTEGRAL EMI FILTER
More results


Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16


Datenblatt Download

Go To PDF Page


Link URL




Privatsphäre und Datenschutz
ALLDATASHEETDE.COM
War ALLDATASHEET hilfreich?  [ DONATE ] 

Über Alldatasheet   |   Werbung   |   Kontakt   |   Privatsphäre und Datenschutz   |   Linktausch   |   Hersteller
All Rights Reserved©Alldatasheet.com


Mirror Sites
English : Alldatasheet.com  |   English : Alldatasheet.net  |   Chinese : Alldatasheetcn.com  |   German : Alldatasheetde.com  |   Japanese : Alldatasheet.jp
Russian : Alldatasheetru.com  |   Korean : Alldatasheet.co.kr  |   Spanish : Alldatasheet.es  |   French : Alldatasheet.fr  |   Italian : Alldatasheetit.com
Portuguese : Alldatasheetpt.com  |   Polish : Alldatasheet.pl  |   Vietnamese : Alldatasheet.vn
Indian : Alldatasheet.in  |   Mexican : Alldatasheet.com.mx  |   British : Alldatasheet.co.uk  |   New Zealand : Alldatasheet.co.nz
Family Site : ic2ic.com  |   icmetro.com