- 您现在的位置：买卖IC网 > PDF目录378296 > AFL27003R3S (International Rectifier) HIGH RELIABILITY HYBRID DC/DC CONVERTER PDF资料下载
参数资料
| 型号： | AFL27003R3S |
| 厂商： | International Rectifier |
| 英文描述： | HIGH RELIABILITY HYBRID DC/DC CONVERTER |
| 中文描述： | 高可靠性的混合式DC / DC转换器 |
| 文件页数： | 6/9页 |
| 文件大小： | 158K |
| 代理商： | AFL27003R3S |
6
www.irf.com
AFL27003R3S
for minor variations of either surface. While other available
types of heat conductive materials and compounds may
provide similar performance, these alternatives are often
less convinient and are frequently messy to use.
A conservative aid to estimating the total heat sink surface
area (A
HEAT SINK
) required to set the maximum case
temperature rise (
T) above ambient temperature is given
by the following expression:
A
HEAT SINK
≈
T
P
80
30
.
0 85
.
143
.
where
T
P
P
Eff
OUT
=
=
=
Case temperature rise above ambient
Device dissipation in Watts
1
1
T = 85 - 25 = 60°C
(
)
P
=
=
=
120
1
83
.
1
120
0205
.
2. W
and the required heat sink area is
A
=
60
80 24.6
in
HEAT SINK
0.85
=
143
.
2
30
.
71
From the Specification Table, the worst case full load
efficiency for this device is 83%; therefore the power
dissipation at full load is given by
Because of the incorporation of many innovative
technological concepts, the AFL series of converters is
capable of providing very high output power from a package
of very small volume. These magnitudes of power density
can only be obtained by combining high circuit efficiency
with effective methods of heat removal from the die junctions.
This requirement has been effectively addressed inside the
device; but when operating at maximum loads, a significant
amount of heat will be generated and this heat must be
conducted away from the case. To maintain the case
temperature at or below the specified maximum of 125°C,
this heat must be transferred by conduction to an
appropriate heat dissipater held in intimate contact with the
converter base-plate.
Because effectiveness of this heat transfer is dependent
on the intimacy of the baseplate/heatsink interface, it is
strongly recommended that a high thermal conductivity heat
transferance medium is inserted between the baseplate
and heatsink. The material most frequently utilized at the
factory during all testing and burn-in processes is sold under
the trade name of Sil-Pad
4001. This particular pro duct
is an insulator but electrically conductive versions are also
available. Use of these materials assures maximum surface
contact with the heat dissipator thereby compensating
When operating in the shared mode, it is important that
symmetry of connection be maintained as an assurance of
optimum load sharing performance. Thus, converter outputs
should be connected to the load with equal lengths of wire of
the same gauge and sense leads from each converter should
be connected to a common physical point, preferably at the
load along with the converter output and return leads. All
converters in a paralleled set must have their share pins
connected together. This arrangement is diagrammatically
illustrated in Figure III. showing the outputs and sense pins
connected at a star point which is located close as possible
to the load.
As a consequence of the topology utilized in the current
sharing circuit, the share pin may be used for other functions.
In applications requiring a single converter, the voltage
appearing on the share pin may be used as a “current
monitor”. The share pin open circuit voltage is nominally
+1.00v at no load and increases linearly with increasing
output current to +2.20v at full load. The share pin voltage
is referenced to the output return pin.
Thus, a total heat sink surface area (including fins, if any) of
71 in2 in this example, would limit case rise to 60°C above
ambient. A flat aluminum plate, 0.25" thick and of
approximate dimension 4" by 9" (36 in2 per side) would
suffice for this application in a still air environment. Note
that to meet the criteria in this example, both sides of the
plate require unrestricted exposure to the ambient air.
1Sil-Pad is a registered Trade Mark of Bergquist, Minneapolis, MN
As an example, it is desired to maintain the case temperature
of an AFL27015S at
≤
+85°C in an area where the ambient
temperature is held at a constant +25°C; then
Thermal Considerations
相关PDF资料 |
PDF描述 |
|---|---|
| AFL27005SW | SM RESISTOR 0402 200 OHM 1% 1/10W |
| AFL27005DW | ADVANCED ANALOG HIGH RELIABILITY HYBRID DC/DC CONVERTERS |
| AFL27005SZ | ADVANCED ANALOG HIGH RELIABILITY HYBRID DC/DC CONVERTERS |
| AFL27009DW | ADVANCED ANALOG HIGH RELIABILITY HYBRID DC/DC CONVERTERS |
| AFL27009DX | ADVANCED ANALOG HIGH RELIABILITY HYBRID DC/DC CONVERTERS |
相关代理商/技术参数 |
参数描述 |
|---|---|
| AFL27003R3SW | 制造商:International Rectifier 功能描述:DC/DC CONVERTER, MINIMUM SCREENING - Bulk |
| AFL27003R3SW/CH | 制造商:International Rectifier 功能描述:DC/DC CONVERTER, CLASS H - Bulk |
| AFL27003R3SW/ES | 制造商:International Rectifier 功能描述:DC/DC CONVERTER, ENVIRONMENTAL SCREENING - Bulk |
| AFL27003R3SW/HB | 制造商:IRF 制造商全称:International Rectifier 功能描述:HIGH RELIABILITY HYBRID DC/DC CONVERTER |
| AFL27003R3SX | 制造商:International Rectifier 功能描述:DC/DC CONVERTER, MINIMUM SCREENING - Bulk |
发布紧急采购，3分钟左右您将得到回复。