AVE300-48S2V5 DC-DC Co nverter TRN
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BOM: 31020640 DATE: 2009-05-13 REV1.3
AVE300-48S2V5 DC/DC Converter
Technical Reference Note
Industry Standard Half Brick: 36~75V Input, 2.5V single Output
Industry Standard Half Brick: 2.4” X 2.28’’ X 0.5’’
Options
• Choice of positive logic or negative logic
for CNT function
• Choice of short pins or long pins
• Choice of with baseplate or without baseplate
Description
The AVE300-48S2V5 is a new DC-DC converter for optimum efficiency and power density.
AVE300-48S2V5 provides up to 60A output current in an industry standard Half Brick, which makes
it an ideal choice for small space and high power applications. AVE300-48S2V5 uses an industry
standard half brick 61.0mm × 57.9mm × 12.7mm (2.4” x 2.28” x 0.5” with baseplate) and 61.0mm ×
57.9mm × 9.5mm (2.4” x 2.28” x 0.375” without baseplate), provides CNT and trim functions.
AVE300-48S2V5 can provide 2.5V@60A, single output and output is isolated from input.
Features
• Delivers up to 60A output current
• Basic isolation
• Ultra High efficiency
• Improved thermal performance:
• High power density
• Low output noise
• 2:1 wide input voltage of 36-75V
• CNT function
• Remote sense
• Trim function: +10%/-20%
• Input under-voltage lockout
• Output over-current protection
• Output over-voltage protection
• Over-temperature protection
• RoHS compliant
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OPTIONS.........................................................................................................................................................1
DESCRIPTION..................................................................................................................................................1
MODULE NUMBERING...............................................................................................................................4
ELECTRICAL SPECIFICATIONS ..............................................................................................................5
INPUT SPECIFICATIONS...................................................................................................................................5
ABSOLUTE MAXIMUM RATINGS.....................................................................................................................6
OUTPUT SPECIFICATIONS ...............................................................................................................................7
OUTPUT SPECIFICATIONS (CONT)...................................................................................................................8
OUTPUT SPECIFICATIONS (CONT)...................................................................................................................8
0FEATURE SPECIFICATIONS ............................................................................................................................9
CHARACTERISTIC CURVES ...................................................................................................................10
PERFORMANCE CURVES – STARTUP CHARACTERISTICS...............................................................................11
FEATURE DESCRIPTION..........................................................................................................................12
CNT FUNCTION............................................................................................................................................12
TRIM.............................................................................................................................................................13
MINIMUM LOAD REQUIREMENTS.................................................................................................................14
OUTPUT OVER-CURRENT PROTECTION ........................................................................................................14
OUTPUT CAPACITANCE.................................................................................................................................14
DECOUPLING................................................................................................................................................14
GROUND LOOPS ...........................................................................................................................................15
OUTPUT OVER-VOLTAGE PROTECTION........................................................................................................15
OVER-TEMPERATURE PROTECTION..............................................................................................................15
DESIGN CONSIDERATION.......................................................................................................................15
TYPICAL APPLICATION .................................................................................................................................15
FUSING.........................................................................................................................................................16
INPUT REVERSE VOLTAGE PROTECTION.......................................................................................................16
EMC ............................................................................................................................................................16
SAFETY CONSIDERATION..............................................................................................................................17
THERMAL CONSIDERATION..................................................................................................................18
TECHNOLOGIES ............................................................................................................................................18
BASIC THERMAL MANAGEMENT..................................................................................................................18
Experiment Setup.....................................................................................................................................19
Convection Without Heatsinks.................................................................................................................19
Heatsink Configuration ...........................................................................................................................19
Heatsink Mounting ..................................................................................................................................20
INSTALLATION..............................................................................................................................................20
SOLDERING ..................................................................................................................................................20
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MECHANICAL CHART ............................................................................................................................. 21
ORDERING INFORMATION .................................................................................................................... 22
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Module Numbering
AVE 300 - 48 S 2V5 PB - 4
CNT logic, P---positive, open frame, by default:
negative, open frame, B---negative, baseplated,
PB---positive & baseplated
Output rated voltage: 2V5---2.5V
Output number: S ---single output, D---dual output
Input rated voltage
Output rated power
Series name
Pin length: 4---4.8mm ± 0.5mm
6---3.80mm 0.5mm
8---2.80mm+0.5mm/-0.3mm
Default is 5.8 mm 0.5mm
±
±
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Electrical Specifications
Unless otherwise indicated, specifications apply over all operating input voltage and temperature
conditions. Standard test condition on a single unit is as following:
Ta: 25 °C
+Vin: 48V ± 2%
-Vin: return pin for +Vin
CNT: connect to -Vin
+Vout: connect to load
-Vout: connect to load (return)
+Sense: connect to +Vout
-Sense: connect to -Vout
Trim (Vadj): Open
Input Specifications
Parameter Symbol Min Typ Max Unit Note
Operating Input Voltage VI 36 48 75 VDC
Inrush transient - - - 1 A2s
-
Input Reflected-ripple Current I
I - 15 25 mAp-p
5Hz to 20MHz: 12µH source
impedance, TA = 25ºC.
Supply voltage rejection (ac) - 45 60 - dB 120Hz
CAUTION: This power module is not internally fused. An input line fuse must always be used.
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Absolute Maximum Ratings
Stresses in excess of the absolute maximum ratings can cause permanent damage to the device.
These are absolute stress ratings only. Functional operation of the device is not implied at these or
any other conditions in excess of those given in the operational sections of the IPS. Exposure to
absolute maximum ratings for extended periods can adversely affect device reliability.
Parameter Symbol Min Typ Max Unit Note
Continuous VI 0 - 80 Vdc
Input Voltage
Transient VI, trans 0 - 100 Vdc 100ms
Operating Ambient Temperature Ta -40 - 85 ºC
See Thermal
Consideration
Operating Board Temperature
without baseplate Tc 105 - 120 ºC
Near temperature sensor
Rt
Operating Board Temperature
With baseplate Tc 100 - 115 ºC Center of baseplate
Storage Temperature TSTG -55 - 125 ºC
Operating Humidity - - - 95 %
Basic Input-Output
Isolation(without baseplate) - 1,500 - - Vdc
1mA for 5 sec,
slew rate of
1,500V/10sec
Basic Input-Baseplate
Isolation(with baseplate) - 1,500 - - Vdc
1mA for 5 sec, slew rate
of 1,500V/10sec
Basic Output-Baseplate
Isolation(with baseplate) - 500 - - Vdc
1mA for 5 sec, slew rate
of 1,500V/10sec
Basic Input-Output Isolation(with
baseplate) - 1,500 - - Vdc
1mA for 5 sec, slew rate
of 1,500V/10sec
Output Power Po,max - - 150 W
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Output Specifications
Parameter Symbol Min Typ Max Unit Conditions
- - 75 100
mVp-p
(f<20M
Hz)
(Ta:25ºC, Air velocity:
300LFM, Vin: 48V,
Vonom, Ionom,10u
tantalum(ESR≤100 m
Ω)// 1µ ceramic
capacitor)
Output Ripple& Noise
- - 100 150
mVp-p
(f<20M
Hz)
Whole range
External Load Capacitance - 470 2200 10000 F
Output Voltage Setpoint Vo,set 2.47 2.5 2.53 Vdc Rating input@ Ionom
Line
(Vi,min to Vi,max) - - - 5 mv
Load
(Io = Io,min to
Io,max)
- - - 10 mv
Output
Regulation
Temperature
Regulation
(Whole range)
-- -- -- 0.02 %Vo/ºC
Whole range
Rated Output Current Io 0 - 60 A
Output Current-limit Inception
(Hiccup) Io 66 - 84 A
Efficiency - 89 91 - %
Ta:25ºC Air velocity:
300LFM Vin: 48V
Load: Ionom; forced
air direction: from Vin+
to Vin-
Efficiency - 90 92 - %
Ta:25ºC Air velocity:
300LFM Vin: 48V
Load: 50% Ionom;
forced air direction:
from Vin+ to Vin-
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Output Specifications (Cont)
Parameter Symbol Min Typ Max Unit Note
Peak
Deviation: - - 100 150 mV
Settling Time
(to Vo,nom): - - 200 500 sec
25% Ionom step from
50%Ionom, 0.1A/S
Peak Deviation - - - 200 mV
Settling Time
(to Vo,nom) - - - - sec
50% Ionom step from
50%Ionom, 0.1A/S:
Peak Deviation - - - 250 mV
Dynamic
Response (all)
Settling Time
(to Vo,nom) - - - - sec
10% Ionom to 100%Ionom,
0.1A/S
Output Specifications (Cont)
Parameter Symbol Min Typ Max Unit Note
Turn-On Time - - - 20 msec Io = Ionom;
Vo from 10% to 90%
Output Voltage Overshoot - - - 5 %Vo Io = Ionom;
TA = 25°C
Switching Frequency - - 240 - KHz
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0Feature Specifications
Parameter Symbol Min Typ Max Unit Note
Logic Low -0.7 - 1.2 Vdc
Enable pin
voltage: Logic High 3.5 - 12 Vdc
Logic Low - - 1.0 mA
Enable pin
current: Logic High - - - A
Output Voltage Adjustment Range - 80 - 110 %Vo -
Output Over-voltage Protection (Static) Voclamp 2.9 - 3.4 V Hiccup
Output Over-voltage Protection (Dynamic) Voclamp 2.9 3.8 V Hiccup
Turn-on Point - 31 34 36 V
Under-voltage
Lockout Turn-off Point - 30 33 35 V
-
Isolation Capacitance - - - - PF
Isolation Resistance - 10 - - M
Calculated MTBF - - 2,000,000 - Hours
Vin: 48V,
Load: Ionom
Board@25°C
- - 103 - g(oz.) With baseplate
Weight
- - 72 - g(oz.) Without baseplate
Vibration (Sine wave)
Vibration level: 3.5mm (2 ~ 9Hz), 10m/s2 (9 ~ 200HZ), 15m/s2 (200 ~
500HZ)
Directions and time: 3 axis (X, Y, Z), 30 minutes each
Sweep velocity: 1oct / min
Shock (Half-sine wave)
Peak acceleration: 300m/s2
Duration time: 6ms
Continuous shock 3 times at each of 6 directions ( ± X, ± Y, ± Z)
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Characteristic Curves
85
87
89
91
93
95
0 102030405060
IO (A)
Efficiency(%)
Vin=48V
Vin=36V
Vin=75V
Fig.1 AVE300-48S2V5-4 Typical Efficiency
Ta: 2 5°C, Air velocity : 300LFM, Vin: 48V, Load: Ionom; forced air direction: from Vin+ to Vin-.
Fig.2 AVE300-48S2V5-4 Typical Output Ripple Voltage
Ta: 2 5oC, Air velocity: 300LFM, Vin: 48V, Vonom, Ionom,10 tantalum(ESR≤100 m)// 1ceramic capacitor
Fig3 AVE300-48S2V5-4 Typical Transient Response to Fig4 AVE300-48S2V5-4.Typical Transient Response to
Ta: 2 5℃, Air velocity: 300LFM, forced air direction: Ta:25 ℃, Air velocity: 300LFM, forced air direction:
from Vin+ to Vin-. Vin: 48V, Vonom, 25% Ionom step from Vin+ to Vin-. Vin: 48V, Vonom, 50% Ionom
step from 50% Ionom, 0.1A/µs ”, the external capacitor from 75% Ionom, 0.1A/µs ”, the external capacitor
should be “10µ tantalum(ESR≤100 m) // 1µ ceramic should be “10µ tantalum(ESR≤100 m) // 1µ ceramic
capacitor. capacitor.
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Performance Curves – Startup Characteristics
Fig.5 Typical start-up from power on Fig.6 Typical start-up from CNT on
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Feature Description
CNT Function
Two CNT logic options are available. The CNT
logic, CNT voltage and the module working
state are as the following table.
L H OPEN
N ON OFF OFF
P OFF ON ON
N--- means “Negative Logic”
P--- means “Positive Logic”
L--- means “Low Voltage”, -0.7V≤L≤1.2V
H--- means “High Voltage”, 3.5V≤H≤12V
ON--- means “Module is on”, OFF--- means
“Module is off”
Open--- means “CNT pin is left open “
Note: when CNT is left open, VCNT may reach
6V.
Figure 7 shows a few simple CNT circuits.
Fig.7 CNT circuits
Remote Sense
AVE300-48S2V5 converter can remotely sense
both lines of its output which moves the
effective output voltage regulation point from
the output terminals of the unit to the point of
connection of the remote sense pins. This
feature automatically adjusts the real output
voltage of AVE300-48S2V5 in order to
compensate for voltage drops in distribution
and maintain a regulated voltage at the point of
load.
When the converter is supporting loads far
away, or is used with undersized cabling,
significant voltage drop can occur at the load.
The best defense against such drops is to
locate the load close to the converter and to
ensure adequately sized cabling is used. When
this is not possible, the converter can
compensate for a drop of up to 10%Vo, through
use of the sense leads.
When used, the + Sense and - Sense leads
should be connected from the converter to the
point of load as shown in Figure 8, using
twisted pair wire, or parallel pattern to reduce
noise effect. The converter will then regulate its
output voltage at the point where the leads are
connected. Care should be taken not to
reverse the sense leads. If reversed, the
converter will trigger OVP protection and turn
off. When not used, the +Sense lead must be
connected with +Vo, and -Sense with -Vo.
Although the output voltage can be increased
by both the remote sense and trim, the
maximum increase for the output voltage is not
the sum of both.
The maximum increase is the larger of either
the remote sense or the trim.
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Note that at elevated output voltages the
maximum power rating of the module remains
the same, and the output current capability will
decrease correspondingly.
Figure 8 Sense connection
Trim
The +Vo output voltage of AVE300-48S2V5
can be trimmed using the trim pin provided.
Applying a resistor to the trim pin through a
voltage divider from the output will cause the
+Vo output to increase by up to 10% or
decrease by up to 20%. Trimming up by more
than 10% of the nominal output may activate
the OVP circuit or damage the converter.
Trimming down more than 20% can cause the
converter to regulate improperly. If the trim pin
is not needed, it should be left open.
Trim up
With an external resistor connected between
the TRIM and +SENSE pins, the output voltage
set point increases (see Figure 9).
Figure 9 Trim up circuit
The following equation determines the required
external-resistor value to obtain a percentage
output voltage change of %.
Note: y is the adjusting percentage of the
voltage. 0<y<10. Radj-up is in k.
Trim down
With an external resistor between the TRIM
and -SENSE pins, the output voltage set point
decreases (see Figure 10).
Figure 10 Trim down circuit
The following equation determines the required
external-resistor value to obtain a percentage
output voltage change of %.
Note: y is the adjusting percentage of the
voltage. 0<y<10. Radj-up is in k.
Although the output voltage can be increased
by both the remote sense and by the trim, the
maximum increase for the output voltage is not
the sum of both. The maximum increase is the
larger of either the remote sense or the trim.
Note that at elevated output voltages the
maximum power rating of the module remains
the same, and the output current capability will
decrease correspondingly.
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Minimum Load Requirements
There is no minimum load requirement for the
AVE300-48S2V5 module.
Parameter Device Symbol Typ Unit
Minimum
Load 2.5V IMIN 0 A
Output Over-current Protection
AVE300-48S2V5 DC/DC converter feature
foldback current limiting as part of their
Over-current Protection (OCP) circuits. When
output current exceeds 110 to 140% of rated
current, such as during a short circuit condition,
the module will work on intermittent mode, also
can tolerate short circuit conditions indefinitely.
When the over-current condition is removed,
the converter will automatically restart.
Output Capacitance
High output current transient rate of change
(high di/dt) loads may require high values of
output capacitance to supply the instantaneous
energy requirement to the load. To minimize
the output voltage transient drop during this
transient, low Equivalent Series Resistance
(ESR) capacitors may be required, since a high
ESR will produce a correspondingly higher
voltage drop during the current transient.
When the load is sensitive to ripple and noise,
an output filter can be added to minimize the
effects. A simple output filter to reduce output
ripple and noise can be made by connecting a
capacitor C1 across the output as shown in
Figure 11. The recommended value for the
output capacitor C1 is 2200F.
Figure 11 Output ripple filter
Extra care should be taken when long leads or
traces are used to provide power to the load.
Long lead lengths increase the chance for
noise to appear on the lines. Under these
conditions C2 can be added across the load,
with a 1F ceramic capacitor C2 in parallel
generally as shown in Figure 12.
Figure 12 Output ripple filter for a distant load
Decoupling
The converter does not always create noise on
the power distribution system. High-speed
analog or digital loads with dynamic power
demands can cause noise to cross the power
inductor back onto the input lines. Noise can be
reduced by decoupling the load. In most cases,
connecting a 10F ceramic capacitor in parallel
with a 0.1F ceramic capacitor across the load
will decouple it. The capacitors should be
connected as close to the load as possible.
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Ground Loops
Ground loops occur when different circuits are
given multiple paths to common or earth
ground, as shown in Figure 13. Multiple ground
points can slightly different potential and cause
current flow through the circuit from one point
to another. This can result in additional noise in
all the circuits. To eliminate the problem,
circuits should be designed with a single
ground connection as shown in Figure 14.
Figure 13 Ground loops
Figure 14 Single point ground
Output Over-Voltage Protection
The output over-voltage protection consists of
circuitry that monitors the voltage on the output
terminals. If the voltage on the output terminals
exceeds the over voltage protection threshold,
then the module will work on hiccup mode.
When the over-voltage condition is removed,
the converter will automatically restart.
The protection mechanism is such that the unit
can continue in this condition until the fault is
cleared.
Over-Temperature Protection
These modules feature an over-temperature
protection circuit to safeguard against thermal
damage. The module will work in intermittent
mode when the maximum device reference
temperature is exceeded. When the
over-temperature condition is removed, the
converter will automatically restart.
Design Consideration
Typical Application
Fig 15 Typical application
F1: Fuse*: Use external fuse (fast blow type)
for each unit.
For 1.5V output: 5A (Pout=90W)
C1: Recommended input capacitor C1
100F/100V electrolytic or ceramic type
capacitor.
C2: Recommended -5°C ~ 100°C uses:
2,200F/10V (electrolytic capacitor)
-40°C ~ -5°C: For this temperature range, use
2,200F/50V electrolytic capacitor and
220F/10V tantalum capacitor.
C3: Recommended 1F/10V
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Fusing
The AVE300-48S2V5 power module has no
internal fuse. An external fuse must always be
employed! To meet international safety
requirements, a 250 Volt rated fuse should be
used. If one of the input lines is connected to
chassis ground, then the fuse must be placed
in the other input line.
Standard safety agency regulations require
input fusing. Recommended fuse ratings for the
AVE300-48S2V5 are shown as following list.
For 1.5V output : 5A (Pout=90W)
Note: the fuse is fast blow type.
Input Reverse Voltage Protection
Under installation and cabling conditions where
reverse polarity across the input may occur,
reverse polarity protection is recommended.
Protection can easily be provided as shown in
Figure 16. In both cases the diode used is
rated for 15A/100V. Placing the diode across
the inputs rather than in-line with the input
offers an advantage in that the diode only
conducts in a reverse polarity condition, which
increases circuit efficiency and thermal
performance.
Figure 16 Reverse polarity protection circuit
EMC
For conditions where EMI is a concern, a different input filter can be used. Figure 10 shows a filter
designed to reduce EMI effects. AVE300-48S2V5 can meet EN55022 CLASS A with Figure 17.
Figure 17 EMI reduction filter
Recommended values:
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Component Value / Rating Type
Cin1 100F Aluminum Electrolytic
CX1 4.7F Metal film or ceramic high frequency capacitor
L1 4mH Mn-Zn Common mode
Core 20
CX2
CY1, CY2 0.22u /275V Safety Y capacitor
CY3, CY4 0.047F Safety Y capacitor
CY5, CY6 0.047F Safety Y capacitor
CY5A, CY6A 0.47F Safety Y capacitor
CY7, CY8 33nF Safety Y capacitor
Cout1 2200F/16V Aluminum Electrolytic
Cout2 1F/63V Metal film capacitor
Cout3 1F/50V/SC1206 Chip Capacitor
Coi 0.022μF Safety Y capacitor
Safety Consideration
For safety-agency approval of the system in
which the power module is used, the power
module must be installed in compliance with the
spacing and separation requirements of the
end-use safety agency standard, i.e., UL60950,
CSA C22.2, and EN60950. AVE300-48S2V5
input-to-output isolation is a basic insulation.
The DC/DC power module should be installed in
end-use equipment, in compliance with the
requirements of the ultimate application, and is
intended to be supplied by an isolated
secondary circuit. When the supply to the
DC/DC power module meets all the
requirements for SELV (<60Vdc), the output is
considered to remain within SELV limits (level 3).
If connected to a 60Vdc power system, double
or reinforced insulation must be provided in the
power supply that isolates the input from any
hazardous voltages, including the ac mains.
One input pin and one output pin are to be
grounded or both the input and output pins are
to be kept floating. Single fault testing in the
power supply must be performed in combination
with the DC/DC power module to demonstrate
that the output meets the requirement for SELV.
The input pins of the module are not operator
accessible.
Note: Do not ground either of the input pins of
the module, without grounding one of the output
pins. This may allow a non-SELV voltage to
appear between the output pin and ground. The
circuit cannot withstand transient over-voltage.
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Thermal Consideration
Technologies
AVE300-48S2V5modules have ultra high
efficiency at full load. With less heat dissipation
and temperature-resistant components such as
ceramic capacitors, these modules exhibit good
behavior during pro-longed exposure to high
temperatures. Maintaining the operating board
temperature within the specified range help
keep internal component temperatures within
their specifications which in turn help keep
MTBF from falling below the specified rating.
Proper cooling of the power modules is also
necessary for reliable and consistent operation.
Basic Thermal Management
Measuring the board temperature of the module
is shown in Figure 18 (with baseplate) and
Figure 19(without baseplate) can verify the
proper cooling.
Figure 18 Temperature measurement location(with
baseplate)
Figure 19 Temperature measurement location(without
baseplate)
The module should work under 85°C ambient for
the reliability of operation and the board
temperature must not exceed 105°C(without
baseplate) or 100°C(with baseplate) while
operating in the final system configuration. The
measurement can be made with a surface probe
after the module has reached thermal
equilibrium. No heatsink is mounted, make the
measurement as close as possible to the
indicated position. It makes the assumption that
the final system configuration exists and can be
used for a test environment. Note that the board
temperature of module must always be checked
in the final system configuration to verify proper
operational due to the variation in test conditions.
Thermal management acts to transfer the heat
dissipated by the module to the surrounding
environment. The amount of power dissipated
by the module as heat (PD) is got by the
equation: PD = PI-PO
Where PI is input power; PO is output power;
PD is dissipated power.
Also, module efficiency (η) is defined as the
following equation: η = PO / PI
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If eliminating the input power term, from two
above equations can yield the equation below:
PD = PO (1-η) / η
The module power dissipation then can be
calculated through the equation.
Because each power module output voltage has
a different power dissipation curve, a plot of
power dissipation versus output current over
three different line voltages is given in the
following figures.
Module Derating
Experiment Setup
From the experimental set up shown in Figure
20, the derating curves as Figure 22 can be
drawn. Note that the Printed Wiring Board (PWB)
and the module must be mounted vertically. The
Passage has a rectangular cross-section. The
clearance between the facing PWB and the top
of the module is kept 13 mm (0.5 in.) constantly.
Figure 20 Experiment setup
Convection Without Heatsinks
Increasing the airflow over the module can
enhance heat transfer. Figure 21 and figure 22
shows the change of the module output current
with the change of ambient temperature. In the
test, the airflow was created with externally
adjustable fans. The appropriate airflow for a
given operating condition can be determined
through this figure.
0
10
20
30
40
50
60
70
0 102030405060708090
Temperature, Ta (℃)
Output Current Io (A)
0m/s 1m/s 2m/s
Figure 21 Forced convection power derating without
baseplate
Airflow direction from Vin(+) to Vin(-): Vin=48V;
0
10
20
30
40
50
60
70
0 10 2030405060708090
Temperature, Ta (℃)
Output Current Io (A)
0m/s 0.5m/s 1m/s
Figure 22 Forced convection power derating
with baseplate
Airflow direction from Vin(+) to Vin(-): Vin=48V
Heatsink Configuration
Several standard heatsinks available for the
AVE300-48S2V5 are shown in Figure 23 to 25.
The heatsinks mounted to the top surface of the
module with screws torqued to 0.56 N-m (5
in.-Ib). A thermally conductive dry pad or thermal
grease is placed between the case and the
heatsink to minimize contact resistance
(typically 0.1°C/W to 0.3°C /W) and temperature
differential.
AVE300-48S2V5 DC-DC Co nverter TRN
TEL: (86) 755-86010808 www.emersonnetworkpower.com.cn 20/22
Nomenclature for heatsink configurations is:
WDxyyy40
x = fin orientation: longitudinal (L) or transverse
(T)
yyy = heatsink height (in 100ths of inch)
For example, WDT5040 is a heatsink that is
transverse mounted for a 61mm × 57.9mm
(2.4in × 2.28in) module with a heatsink height of
0.5 in.
Figure 23 Non-standard heatsink
Figure 24 Longitudinal fins heatsink
Figure 25 Transverse fins heatsink
Heatsink Mounting
A crucial part of the thermal design strategy is
the thermal interface between the baseplate of
the module and the heatsink. Inadequate
measures taken will quickly negate any other
attempts to control the baseplate temperature.
For example, using a conventional dry insulator
can result in a case-heatsink thermal impedance
of >0.5oC/W, while use one of the recommended
interface methods (using silicon grease or
thermal pads) can result in a case-heatsink
thermal impedance around 0.1oC/W.
Figure 26 Heatsink mounting
Installation
Although AVE300-48S2V5 converters can be
mounted in any orientation, free air-flowing must
be taken. Normally power components are
always put at the end of the airflow path or have
separate airflow paths. This can keep other
system equipment cooler and increase
component life spans.
Soldering
AVE300-48S2V5 converter is compatible with
standard wave soldering techniques. When
wave soldering, the converter pins should be
preheated for 20-30 seconds at 110oC, and
wave soldered at 260oC (less than 10 seconds).
When hand soldering, the iron temperature
should be maintained at 425oC and applied to
the converter pins for less than 5 seconds.
Longer exposure can cause internal damage to
the converter. Cleaning can be performed with
cleaning solvent IPA or with water.
Assembly
The maximum length of the screw driven into the
heat-sink is 3.3mm.
AVE300-48S2V5 DC-DC Co nverter TRN
TEL: (86) 755-86010808 www.emersonnetworkpower.com.cn 21/22
Mechanical Chart
With no base plate:
With base plate:
AVE300-48S2V5 DC-DC Co nverter TRN
TEL: (86) 755-86010808 www.emersonnetworkpower.com.cn 22/22
Ordering Information
Model Number Input
Voltage
(V)
Output
Voltage
(V)
Output
Current
(A)
Ripple
&Noise
(mV pp,
Max.)
Efficiency
(%)
Typ.
AVE300-48S2V5-4 36-75 2.5 60 150 91
AVE300-48S2V5B-4 36-75 2.5 60 150 91
