ASTEC AIF25R48_03

AIF25R48 Series Technical Reference Note
AIF25R48 Series Isolated DC/DC Converter Module
36-75V Input, 28V single Output
Features
Industry Standard Size: 4.6”X 2.4’’ 0.5’’package
Options
•
•
•
•
•
•
•
•
•
4.6’’ X 2.4’’ X 0.5’’ full brick package
Basic insulation
High efficiency
High power density
Current sharing function
2:1 wide input range of 36-75V
CNT (input side and output side) function
Trim function
•
•
•
•
•
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AUX/IOG/TMP signal output
Over- temperature protection
Input under-voltage protection
Output short circuit protection
Output over-voltage protection
Wide operating case temperature range
Sense function
Choice of positive logic or negative logic for CNT function
Choice of short pins or long pins
Description
The AIF25R48 series is a new Aluminum baseplate full brick DC-DC converter. The
AIF25R48 series uses an industry standard package size: 116.8mm X 61mm X 12.7mm
(4.6”x2.4”x0.5”), provides CNT, current sharing, trim,
sense, and IOG/TMP functions.
AIF25R48 series comes in 48V input versions, each of which uses a 2:1 input range of
36~75V. It can provide [email protected] single output, which is isolated from input.
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AIF25R48 Series Technical Reference Note
Contents
Options ................................................................................................................................................................. 1
Description............................................................................................................................................................ 1
Electrical Specifications ............................................................................................................................................ 4
Input Specifications ............................................................................................................................................... 4
Absolute Maximum Ratings .................................................................................................................................. 5
Output Specifications ............................................................................................................................................ 6
Output Specifications (Cont).................................................................................................................................. 7
Feature Specifications............................................................................................................................................ 8
Characteristic Curves ................................................................................................................................................ 9
Performance Curves – Efficiency........................................................................................................................... 9
Performance Curves – Output Performance Curves................................................................................................ 9
Performance Curves – Transient Response........................................................................................................... 10
Performance Curves – Transient Response (Cont)................................................................................................ 10
Performance Curves – Startup Characteristics ...................................................................................................... 11
Performance Curves – Startup from CNT1 Control .............................................................................................. 11
Feature Description ................................................................................................................................................. 12
CNT Function ..................................................................................................................................................... 12
Trim .................................................................................................................................................................... 13
Minimum Load Requirement ............................................................................................................................... 14
Output Over-Current and Short Protection ........................................................................................................... 14
Output Over-Voltage Protection ........................................................................................................................... 14
Over Temperature Protection ............................................................................................................................... 14
Current Sharing ................................................................................................................................................... 15
Sense................................................................................................................................................................... 16
AUX/IOG/TMP................................................................................................................................................... 18
Output Filter........................................................................................................................................................ 18
Decoupling.......................................................................................................................................................... 19
Ground Loops ..................................................................................................................................................... 19
Design Consideration .............................................................................................................................................. 21
Typical Application ............................................................................................................................................. 21
Fusing ................................................................................................................................................................. 21
Input Reverse Voltage Protection ......................................................................................................................... 21
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AIF25R48 Series Technical Reference Note
EMC ................................................................................................................................................................... 22
Safety Consideration............................................................................................................................................ 23
Thermal Management.............................................................................................................................................. 24
Technologies ....................................................................................................................................................... 24
Basic Thermal Management ................................................................................................................................ 24
Module Derating with Heatsink ........................................................................................................................... 25
Module Derating without Heatsink ...................................................................................................................... 26
MTBF..................................................................................................................................................................... 26
Mechanical Considerations...................................................................................................................................... 27
Installation .......................................................................................................................................................... 27
Soldering............................................................................................................................................................. 27
Mechanical Chart (pin side view)......................................................................................................................... 28
Ordering Information .............................................................................................................................................. 29
Model Numbering ................................................................................................................................................... 29
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AIF25R48 Series Technical Reference Note
Electrical Specifications
Unless otherwise indicated, specifications apply over all operating input voltage and
temperature conditions. Standard test condition on a single unit with a heatsink of 270mm
220mm 43mm is as following:
Tc(case):
25°C
+Vin:
48V 2%
−Vin:
Return pin for +Vin
CNT1:
Connect to -Vin
+Vout:
Connect to load
−Vout:
Connect to load (return)
+Sense:
Connect to +Vout
-Sense:
Connect to -Vout
VB, Trim(Vadj):
Open
CNT2, CNT3:
Open
CB:
Open
IOG, TMP:
Open
AUX:
Open
Input Specifications
Parameter
Device
Symbol
Min
Typ
Max
Unit
Operating Input Voltage
All
VI
36
48
75
VDC
Maximum Input Current
All
Ii,max
-
-
23
A
All
Ii
-
-
160
mAp-p
All
-
-
-
7
W
(Vi = 0 to Vi,max, Io = Io,max)
Input Reflected-ripple Current
(Vi = Vi,nom ,
5Hz to 20MHz: 12uH source
impedance: Tc = 25 ºC.)
No Load Input Power
(Vi = Vi,nom )
CAUTION: This power module is not internally fused. An input line fuse must always be used.
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AIF25R48 Series Technical Reference Note
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 in 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
Device
Symbol
Min
Typ
Max
Unit
Input Voltage:
Continuous:
Transient (100ms)
All
All
Vi
VI, trans
0
0
-
80
100
Vdc
Vdc
Highest voltage to CNT1
All
-
-
-
15
Vdc
Operating Ambient
Temperature
All
Ta
-20
55
ºC
Operating Case Temperature
(with a heatsink)
All
Tc
-
-
100
ºC
Storage Temperature
All
TSTG
-55
-
125
ºC
Operating Humidity
All
-
-
-
85
%
All
-
-
-
1500
1500
500
Vdc
Vdc
Vdc
All
Po,max
-
-
700
W
I/O Isolation
(Conditions : 50µA for 5 sec,
slew rate of 1500V/10sec)
Input-Output
Input-Case
Output-Case
Output Power
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AIF25R48 Series Technical Reference Note
Output Specifications
Parameter
Device
Symbol
Min
Typ
Max
Unit
Output Ripple and Noise
All
-
-
100
200
mVp-p
External Load Capacitance
All
-
470
1000
6800
µF
Output Voltage Setpoint
(Vi = Vinom: Io =18A; Tc = 25
ºC )
Output Regulation:
All
Vo,set
27.5
28
28.5
Vdc
Line (Vi,min to Vi,max)
All
-
-
0.01
0.2
%
Load(Io = Io,min to Io,max)
All
-
-
0.1
0.5
%
Temperature
All
-
-
-
0.02
%Vo/ºC
Rated Output Current
All
Io
2.5
-
25
A
Output Current-limit Inception
All
Io
26.25
-
35
A (RMS)
86
89
-
%
(Across
1µF
@50V,
X7R
ceramic
capacitor & 1000µF @50V LOW ESR
Aluminum capacitor)
Peak-to-Peak (5 Hz to 20
MHz)
(when unit is shut down)
Efficiency
All
(Vi = Vi,nom ; Io,nom ; Tc= 25°C)
Switching Frequency
DATE: May 28, 2003
All
-
MODEL : AIF25R48 SERIES
340
KHz
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AIF25R48 Series Technical Reference Note
Output Specifications (Cont)
Parameter
Device
Symbol
Min
Typ
Max
Unit
All
-
-
-
3
500
%Vo,nom
µsec
All
-
-
-
3
500
%Vo,nom
µsec
All
-
-
-
200
msec
All
-
-
-
5
%Vo,nom
Dynamic Response :
(∆Io/∆t = 1A/10µs )
Load Change from Io = 50% to
75% of Io,nom :
Peak Deviation Settling Time (to
Vo,nom)
Load Change from Io = 50% to
25% of Io,nom :
Peak Deviation Settling Time (to
Vo,nom)
Turn-On Time
(Io = Io,nom ; Vo within 1%)
Output Voltage Overshoot
(Io = Io,nom ; TA = 25°C)
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AIF25R48 Series Technical Reference Note
Feature Specifications
Parameter
CNT1 pin voltage :
Logic Low
Logic High
Enable pin current :
Logic Low
Device
Symbol
Min
Typ
Max
Unit
All
All
-0.7
3.5
-
1
7
V
V
All
-
-
1
mA
Output Voltage Adjustment
Range
Output Over-voltage
All
-
80
-
110
%Vo,nom
ALL
-
32.2
-
39.2
V
Over Temperature protect
All
T
101
Turn-on Point
Turn-off Point
All
All
-
31
30
Current Sharing Accuracy
All
-
+SENSE
All
-
1
%Vo,nom
-SENSE
All
-
1
%Vo,nom
AUX
All
-
13
16
V
IOG
All
-
5
V
TMP
All
-
5
V
Isolation Capacitance
All
-
-
1600
-
PF
Isolation Resistance
All
-
10
-
-
MΩ
Calculated MTBF
All
-
-
1,500,
000
-
Hours
All
-
-
150
-
g
120
Under-Voltage Lockout
(Io = Io,nom ; TA = 25°C)
Weight
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34
33
36
35
3
10
V
V
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AIF25R48 Series Technical Reference Note
Characteristic Curves
Performance Curve – Efficiency
Efficiency(%)
95
85
Vin=36V
Vin=48V
75
Vin=75V
65
55
0
5
10
15
20
25
Output Current(A)
Typical Efficiency Curve
Performance Curves – Output Performance Curve
Output Voltage(V)
30
25
20
Vin=36V
15
Vin=48V
Vin=75V
10
5
0
0
10
20
30
40
Output Current(A)
Output Performance Curve
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AIF25R48 Series Technical Reference Note
Performance Curves – Transient Response
50%-25%Ioman load change
Performance Curves – Transient Response (Cont)
25%-50%Ioman load change
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AIF25R48 Series Technical Reference Note
Performance Curves – Startup Characteristics
Start-up from Power On
Performance Curves – Startup from CNT1 Control
Start-up from CNT1 On
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AIF25R48 Series Technical Reference Note
Feature Description
CNT Function
CNT function is available on both side of input (CNT1) and output (CNT2/CNT3).
Input side CNT(CNT1) Function
Two CNT1 logic options are available. The CNT1 logic, CNT1 voltage and the module
working state are as the following Table 1.The ground pin of CNT1 is “-Vin” pin. And
CNT2/CNT3 must be open when CNT1 is used.
L
H
OPEN
N
ON
OFF
OFF
P
OFF
ON
ON
Table 1
N--- means “Negative Logic”, P--- means “Positive Logic”
L--- means “Low Logic Voltage”, -0.7V L 1V
H--- means “High Logic Voltage”, 3.5V H 7V
ON--- means “Module is on”, OFF--- means “Module is off”
Open--- means “CNT1 pin is left open “
Note: Normally, VCNT1
8V, but when CNT1 is left open, VCNT may reach to 15V.
The following Figure shows a few simple CNT1 circuits.
Fig.1 A few simple CNT1 Circuits
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AIF25R48 Series Technical Reference Note
Output Side CNT (CNT2/CNT3) Function
Two CNT2/CNT3 logic options are available. CNT2/CNT3 can be used as shown in Fig2 with
a “Negative Logic” module. The switch is opposite with a “Positive Logic” module. CNT1
must be connected to -Vin when CNT2/CNT3 is used. And make sure that sink current of
output side CNT circuit should be less than 12mA.
Fig.2 Output Side CNT (CNT2/CNT3) Function for “Negative Logic” Module
Trim
The output voltage of the AIF25R48 series can be trimmed using the trim pin provided.
Applying a resistor to the trim pin through a voltage divider from the VB will cause the output
to increase 10% or decrease 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.
Fig.3 Trim Up Circuit and Formula
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AIF25R48 Series Technical Reference Note
Fig.4 Trim Down Circuit and Formula
Minimum Load Requirement
The minimum load of AIF25R48 series is 2.5A.
Output Over-Current and Short Protection
AIF25R48 series DC/DC converters 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.
A sound may occur from module when the output is shorted.
Output Over-Voltage Protection
The over-voltage protection has a separate feedback loop, which activates when the output
voltage exceeds 120% to 140% of the nominal output voltage. The module can restart by
turning on the power or turning on the CNT (CNT1 or CNT2/CNT3) signal again.
Over Temperature Protection
AIF25R48 series DC/DC converters will shut down when the temperature of the baseplate
reaches 101
to 120 , and the module will automatically restart if the temperature of the
baseplate is under 100 . The measurement point is indicated in below Fig 5. The module
must be mounted on a heatsink of 270mm 220mm 43mm when measuring OTP point.
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AIF25R48 Series Technical Reference Note
The OTP point is about 85
without a heatsink.
Fig.5 Measuring OTP Point of AIF25R48 series
Current Sharing
Parallel operation is available by connecting the modules as shown in Fig 6.
As variance of output current drew from each power supply is 10% maximum, the total
output current must not exceed the value determined by the following equation.
(Output current in parallel operation)=(the rated current per module)*(number of module)*0.9
In parallel operation, the maximum operative number of modules is 7.
When output voltage adjustment is not used. TRM, VB open, R1, R2, VR1, Rva, Rvb, Rta,
Rtb… are not needed.
Thick wire should be used for wiring between the power supply and load, and line drop
should be less than 0.3V.
Connect the sensing line and the power line by one point after connecting each power
supply’s sense pins (+Sense, -Sense).
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AIF25R48 Series Technical Reference Note
+VOUT
+SENSE
VB
TRM
CB
-SENSE
-VOUT
Rva
Rta
Csa
Co1a
Co2a
LOAD
VR1
+VOUT
+SENSE
VB
TRM
CB
-SENSE
-VOUT
+VOUT
+SENSE
VB
TRM
CB
-SENSE
-VOUT
Rvb
Rtb
Csb
Rvc
Rtc
Csc
Co1b Co2b
Co1c Co2c
.
.
.
Fig.6 Parallel operation
Rva, Rvb,…..: 470
Rta, Rtb,…: 22K
Vr1
10K
Csa,Csb,…: 0.1 F
Sense
Sense terminal is provided to compensate for voltage drop across the load wire.
When sense function is not used, short +sense terminal to +Vout terminal and, -sense
terminal to –Vout terminal.
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AIF25R48 Series Technical Reference Note
When sense function is used, it should pay attention to that voltage compensation range for
line drop must be less than 1%Vo. Using shield wire, twist pair, or parallel pattern to reduce
noise effect.
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AIF25R48 Series Technical Reference Note
AUX/IOG/TMP
AUX
AUX is built in to operate the output side CNT(CNT2/CNT3).
If AUX is not used for CNT2/CNT3, AUX can be used for IOG or TMP signal output by opto
coupler.
Short protection resistance(2.7k
) is built in.
AUX voltage at open circuit is 13Vtpy, 16Vmax.
IOG
IOG signal turns “H” from “L” within 1 second when the output of the module is shut down.
The specification of IOG is shown in table 2.
TMP
TMP signal turns “L” from “H” within 1 second when over temperature is detected.
The specification of TMP is shown in Table 2.
item
Function
Base pin
Level voltage “L”
Level voltage “H”
Maximum sink current
Maximum applicable voltage
TMP
IOG
Normal operation ”H”
Normal operation ”L”
Over temperature “L”
Malfunction “H”
-Sense
0.5Vmax at 5mA
5V typ
10mA max
35V max
Table 2 The specification of IOG and TMP
Output Filter
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 ‘Output Ripple Filter’. The recommended
value for the output capacitor C1 is 1000µF.
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AIF25R48 Series Technical Reference Note
Fig.7 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 0.47F ceramic capacitor C2 in parallel
generally as shown in Figure ‘Output Ripple Filter for a Distant Load’.
Fig.8 Output Ripple Filter for a Distant Load
Decoupling
Noise on the power distribution system is not always created by the converter. 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 10F tantalum or ceramic capacitor in parallel with a 0.1F ceramic
capacitor across the load will decouple it. The capacitors should be connected as close to
the load as possible.
Ground Loops
Ground loops occur when different circuits are given multiple paths to common or earth
ground, as shown in Figure ‘Ground Loops’. 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 ‘Single Point Ground’.
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AIF25R48 Series Technical Reference Note
Fig.9 Ground Loops
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AIF25R48 Series Technical Reference Note
Design Consideration
Typical Application
F1
+VIN
+VOUT
+SENSE
Vin
Cin
CNT1
TRM
S1
Co1
Co2
LOAD
-SENSE
-VIN
-VOUT
Fig.10 typical application
F1: 30A
Cin: Recommended 470 F/100V low ESR Aluminum capacitor.
Co1: Recommended 1 F/50V film capacitor.
Co2: Recommended 1000 F/50V low ESR Aluminum capacitor.
Fusing
The AIF25R48 series power modules have 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
AIF25R48 series are 30A.
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 ‘Reverse Polarity Protection Circuit’. In both cases the diode used is rated for
40A/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.
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AIF25R48 Series Technical Reference Note
Fig 11 Reverse Polarity Protection Circuit
EMC
For conditions where EMI is a concern, a different input filter can be used. Fig 12 ‘EMI
Reduction Filter‘ shows a filter designed to reduce EMI effects. AIF25R48 SERIES can meet
EN55022 CLASS A with Fig 12.
Vin+
Vout+
+Sense
+Vin
C1
+Vout
C5
C3
L1
L3
C7
+
C2
C8
L2
+
AIF25R48
AVF700
SERIES
+ C10 C11
C12
C9
C6
-Vin
-Vout
Vin-
Vout-Sense
CASE
Fig.12 EMI Reduction Filter
L1, L2: 3.25mH
L3: 110 H
C3, C7: 470 F/100V low ESR Aluminum capacitor.
C10: 1000 F/50V low ESR Aluminum capacitor.
C1, C2: 2.2 F/250V
C5, C6: 0.15 F/250V
C8, C9: 4.7Nf/1000V
C11, C12: 1 F/50V
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AIF25R48 Series Technical Reference Note
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., UL1950, CSA C22.2 No. 950-95, and EN60950. The
AIF25R48 SERIES input-to-output isolation is an 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 Vin pin and one Vout 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.
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AIF25R48 Series Technical Reference Note
Thermal Management
Technologies
AIF25R48 series module has typical efficiency of 89% at full load. With less heat dissipation
and temperature-resistant components such as ceramic capacitors, the module exhibit good
behavior during pro-longed exposure to high temperatures. Maintaining the operating case
temperature (Tc) 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 case temperature of the module (Tc) as the method shown in Figure 5 can
verify the proper cooling. The module should work under 55°C ambient for the reliability of
operation and Tc must not exceed 100°C while operating in the final system configuration.
The measurement can be made with a surface probe after the module has reached thermal
equilibrium. If a heat sink is mounted to the case, 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 Tc 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 below:
Pd = Pi ÄPo
where : Pi is input power; Po is output power; Pd is dissipated power.
Also, module efficiency ( ) is defined as the following equation:
= Po / Pi
If eliminating the input power term, from two above equations can yield the equation below:
Pd = Po (1- ) /
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AIF25R48 Series Technical Reference Note
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 each
module-specific data sheet. The typical power dissipation curve of AIF25R48 SERIES is
shown as Fig.13.
Power Dissipation
120
100
80
Vin=36V
60
Vin=48V
40
Vin=75V
20
0
0
5
10
15
20
25
Output Current(A)
Fig.13 Typical Power Dissipation Curve of AIF25R48 series
Module Derating with Heatsink
Usually a customized heatsink is used for AIF25R48 SERIES because the power dissipation
of AIF25R48 series is too large. A heatsink of full brick size can not consume so much heat.
A derating curve is shown in Fig14 with a heatsink of 270mm
220mm 43mm size. The
module will have different derating curves with different heatsink designed by customer.
Fig.14 Temperature Derating Curve with Heatsink
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AIF25R48 Series Technical Reference Note
Module Derating without Heatsink
The derating curves of AIF25R48 series without heatsink are shown in the following Fig15.
We recommend that the customer use the AIF25R48 SERIES with proper heatsink for the
better operation.
Fig.15 Temperature Derating Curve without Heatsink
MTBF
The MTBF, calculated in accordance with Bellcore TR-NWT-000332 is 1,500,000 hours.
Obtaining this MTBF in practice is entirely possible. If the case temperature is expected to
exceed +25 , then we also advise an oriented for the best possible cooling in the air
stream.
ASTEC can supply replacements for converters from other manufacturers, or offer custom
solutions. Please contact the factory for details.
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MODEL : AIF25R48 SERIES
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AIF25R48 Series Technical Reference Note
Mechanical Considerations
Installation
Although AIF25R48 series 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 the separate airflow paths. This can keep other system equipment cooler and increase
component life spans.
Soldering
AIF25R48 series converters are compatible with standard wave soldering techniques. When
wave soldering, the converter pins should be preheated for 20-30 seconds at 110 , and
wave soldered at 260
for less than 10 seconds.
When hand soldering, the iron temperature should be maintained at 425
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.
DATE: May 28, 2003
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AIF25R48 Series Technical Reference Note
Mechanical Chart (pin side view)
*: Pin length
Default: 4.8mm
0.5mm ( 0.189in. 0.02in.)
Product name with suffix “-6”: 3.8mm 0.25mm ( 0.15in. 0.01in.)
Product name with suffix “-7”: 5.8mm 0.5mm ( 0.228in. 0.02in.)
Product name with suffix “-8”: 2.8mm 0.25mm ( 0.11in. 0.01in.)
DATE: May 28, 2003
MODEL : AIF25R48 SERIES
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AIF25R48 Series Technical Reference Note
Ordering Information
Model Number
AIF25R48
Input Voltage
Output
Output
Ripple
Noise
Efficiency
(V)
Voltage
Current
(mV PP)
(mV pp)
%
(V)
(A)
typ.
typ.
typ.
28
25
160
200
89
36-75
SERIES
Model Numbering
DATE: May 28, 2003
MODEL : AIF25R48 SERIES
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