Board Mountable
DC-DC Converters
IMR 3 Series
3 Watt DC-DC Converters
Input voltage range up to 72 V DC
1 output up to 30 V DC
500 V DC I/O electric strengh test voltage
•
Input voltage range up to 3:1
•
High efficiency up to 73%
•
Short-circuit proof
•
No derating
•
DIL 24 plastic package
•
Low cost
IMR 3 Series
32
1.26"
12
0.47"
20
0.79"
Summary
The IMR 3 serie of DC-DC converters have been devel-
oped for powering commercial type of electronic circuits,
e.g. telephone systems components, industrial controllers
and small appliances. They are suitable for applications
with standard battery voltages. The IMR 3 converters fea-
ture good efficiency and good dynamic response to load
changes and at start-up. The IMR 3 modules are short-cir-
cuit and no-load proof.
Type Survey and Key Data
Table 1: Type survey
Output
Output power Efficiency
1
h
min
P
o max
[W]
[%]
2.3
2.5
3
3
2.5
3
3
63
63
65
65
65
67
67
Input voltage range
U
i min
...
U
i max
18...36 V DC
20...60 V DC
Option
U
o nom
[V]
3.3
5
12
15
±5
±12
±15
1
2
I
o nom
[mA]
700
500
250
200
250
125
100
U
i min
...
U
i max
9...18 V DC
2
12 IMR 3-03-2
12 IMR 3-05-2
12 IMR 3-12-2
12 IMR 3-15-2
12 IMR 3-0505-2
12 IMR 3-1212-2
12 IMR 3-1515-2
U
i min
...
U
i max
U
i min
...
U
i max
36...72 V DC
48 IMR 3-03-2
48 IMR 3-05-2
48 IMR 3-12-2
48 IMR 3-15-2
48 IMR 3-0505-2
48 IMR 3-1212-2
48 IMR 3-1515-2
-7
24 IMR 3-03-2
24 IMR 3-05-2
24 IMR 3-12-2
24 IMR 3-15-2
24 IMR 3-0505-2
24 IMR 3-1212-2
24 IMR 3-1515-2
40 IMR 3-03-2
40 IMR 3-05-2
40 IMR 3-12-2
40 IMR 3-15-2
40 IMR 3-0505-2
40 IMR 3-1212-2
40 IMR 3-1515-2
Efficiency at
U
i nom
and
I
o nom
12 IMR 3 types: Output current
I
o nom
see:
Output Data
Table of Contents
Page
Page
Electrical Output Data ...................................................... 3
Electromagnetic Compatibility (EMC) .............................. 4
Immunity to Environmental Conditions ............................. 4
Mechanical Data .............................................................. 5
Safety and Installation Instructions .................................. 5
1/6
Summary .......................................................................... 1
Type Survey and Key Data .............................................. 1
Type Key .......................................................................... 2
Functional Description ...................................................... 2
Electrical Input Data ......................................................... 2
Edition 4/04.2001
Board Mountable
Type Key
Type Key
DC-DC Converters
IMR 3 Series
24 IMR 3 - 12 12 -2
Nominal input voltage in volt ................................... 12...48
Series .......................................................................... IMR
Nominal output power in watt ........................................... 3
Nominal output voltage for output 1 in volt .............. 05...15
Nominal output voltage for output 2 in volt .............. 05...15
Operational ambient temperature range
T
A
–10...50°C .................................................. -2
–25...71°C (option) ..................................... -7
Functional Description
03060
03059
22
Vi+
Vo+
14
22
Vi+
Vo+
14
23
23
Ref.
C
i
Control
Ref.
2
16
C
o
9
16
C
o
C
i
Control
COM
C
o
11
2
Vi–
3
Vo–
Vi–
3
Vo–
Fig. 1
Single output converter block diagram
Attention:
C
i
= 4.7
µF/100
V must be added in any applica-
tion.
C
o
= 10
µF
to minimize ripple and noise to <100 mV
PP
(Capacitors should be of low ESR types).
Fig. 2
Dual output converter block diagram
Electrical Input Data
General condition:
T
A
= 25°C unless otherwise specified
Table 2a: Input data
Input
Characteristics
Conditions
min
9
12
0
22
18
1.25
P
i nom
shunt diode
use external fuse
0
12
1.25
P
i nom
shunt diode
use external fuse
12 IMR 3
typ
max
18
min
18
24
40
mA
W
24 IMR 3
typ
max
36
Unit
V DC
U
i
U
i nom
U
i
I
i 0
I
i L
U
i rev
Input voltage range
Nominal input voltage
Input voltage without
damage
No load input current
Input current limitation
response
Reverse input voltage
protection
T
A min
...
T
A max
I
o
= 0...
I
o nom
U
i nom
,
I
o
= 0
U
i nom
, full load
U
i
= negative or
reverse polarity
Edition 4/04.2001
2/6
Board Mountable
Table 2b: Input data
Input
Characteristics
Conditions
DC-DC Converters
40 IMR 3
min
20
36
0
75
8
1.25
P
i nom
shunt diode
use external fuse
0
8
1.25
P
i nom
typ
max
60
min
36
48
48 IMR 3
typ
IMR 3 Series
max
72
Unit
V DC
U
i
U
i nom
U
i
I
i 0
I
i L
U
i rev
Input voltage range
Nominal input voltage
Input voltage without
damage
No load input current
Input current limitation
response
Reverse input voltage
protection
T
A min
...
T
A max
I
o
= 0...
I
o nom
75
mA
W
U
i nom
,
I
o
= 0
U
i nom
, full load
U
i
= negative or
reverse polarity
shunt diode
use external fuse
Electrical Output Data
General condition:
T
A
= 25°C unless otherwise specified
Table 3a: Output data for single output types
Output
Characteristics
Conditions
.. IMR 3-03
min typ max
3.24
560
700
300
100
±1
±2
±0.02
50
50
±2
±0.02
50
3.36
.. IMR 3-05
min typ max
4.90
400
500
300
100
±1
±2
±0.02
50
5.10
.. IMR 3-12
min typ max
11.76
200
250
300
100
±1
±2
±0.02
%/K
kHz
12.24
.. IMR 3-15
min typ max
14.70
150
200
300
100
±1
15.30
Unit
V
mA
U
o
I
o nom
Output voltage
Nominal output current:
– 12 IMR 3 types
– other types
Output voltage noise:
– without
C
o
– with
C
o
Static line regulation
Static load regulation
Temperature coefficient
Switching frequency
U
i nom
,
I
o nom
U
i min
...
U
i max
(0.2...1)
I
o nom
U
i nom
I
o nom
(BW = 20 MHz)
u
o
mV
pp
%
D
U
o U
D
U
o I
a
Uo
U
i min
...
U
i max
I
o nom
U
i nom
(0.2...1)
I
o nom
f
s
U
i nom
I
o nom
Table 3b: Output data for dual output types
Output
Characteristics
Conditions
.. IMR 3-0505
min
±4.90
±200
±250
300
100
±1
±5
±0.02
50
50
±5
±0.02
50
typ
max
±5.10
.. IMR 3-1212
min
±11.76
±100
±125
300
100
±1
±5
±0.02
%/K
kHz
typ
max
±12.24
.. IMR 3-1515
min
±14.70
±80
±100
300
100
±1
typ
max
±15.30
Unit
V
mA
U
o
I
o nom
Output voltage
Nominal output current:
– 12 IMR 3 types
– other types
Output voltage noise:
– without
C
o
– with
C
o
Static line regulation
Static load regulation
Temperature coefficient
Switching frequency
U
i nom
,
I
o nom
U
i min
...
U
i max
(0.2...1)
I
o nom
U
i nom
I
o nom
(BW = 20 MHz)
u
o
mV
pp
%
D
U
o U
D
U
o I
a
Uo
U
i min
...
U
i max
,
I
o nom
U
i nom
(0.2...1)
I
o nom
f
s
U
i nom
I
o nom
Edition 4/04.2001
3/6
Board Mountable
Thermal Considerations
DC-DC Converters
Connection in Parallel
IMR 3 Series
If a converter is operated, the relationship between the am-
bient temperature
T
A
and the case temperature
T
C
depends
heavily on the conditions of operation and integration into a
system. The thermal conditions are influenced by input volt-
age, output current, airflow, temperature of surrounding
components and surfaces and the properties of the printed
circuit board. The specified maximum ambient temperature
T
A max
is therefore only an indicative value and under practi-
cal operating conditions, the ambient temperature
T
A
may
be higher or lower than this value.
Caution: The case temperature
T
C
measured at the
Measuring point of case temperature
T
C
(see:
Mechani-
cal Data
) may under no circumstances exceed the
specified maximum value. The installer must ensure that
under all operating conditions
T
C
remains within the lim-
its stated in the table:
Temperature specifications
.
Connection in Series
The outputs of one or more units can be connected in se-
ries. No suppressor diodes are required. Power-One how-
ever recommends to protect each individual output with a
Zener diode or preferably a suppressor diode, to avoid re-
verse polarity that may occur if the output voltages do not
rise simultaneously.
Connecting the outputs of two or more converters in parallel
is not recommended due to uneven power distribution
among the outputs.
Protection Scheme
The IMR series is continuously short circuit protected by
means of input power limitation. The unit will not be dam-
aged if started up into a short circuit. After removal of the
short circuit, it will resume normal operation.
The IMR series is also no-load proof, meaning that the
regulation is still effective with no load and the output volt-
age does not rise. However, due to component tolerances,
oscillation could occur and ripple and noise can be outside
of specified values. If the converter is used in senitive elec-
tronic circuits with no-load conditions, it is recommended to
pre-load the outputs with at least 20% of the specified
nominal load.
Electromagnetic Compatibility (EMC)
07025
Filter recommendations for compliance with
CISPR 22/EN 55022, class B
Electromagnetic emission requirements according to EN
55022, class B can be easely achieved by adding an exter-
nal input filter consisting of three additional capacitors and
one commom mode ring core choke.
The filter components should be placed as close as possi-
ble to the input of the converter.
C
1
C
2
L
1
Vi+
C
i
Vi–
Fig. 3
Input filter arrangement
Table 4: Input filter components
Input voltage
12, 24, 40, 48 V DC
C
1
2.2
µF
1
100 V
C
2
2.2
µF
1
100 V
Type
Siemens
B 32522
C1225-K
L
1
2.2 mH
Type
Siemens
B 82722
A2202-N1
C
i
4.7
µF
100 V
Type
Al-Chip
(low ESR)
1
Only valid for input voltages up to 60 V DC.
Immunity to Environmental Conditions
Table 5: Temperature specifications, valid for air pressure of 800...1200 hPa (800...1200 mbar)
Temperature
Characteristics
Conditions
Standard -2
min
–10
–10
–25
max
50
80
85
min
–25
–25
–40
Option -7
max
71
85
100
Unit
°C
T
A
T
C
T
S
Ambient temperature
Case temperature
Storage temperature
U
i nom
I
o
=
I
o nom
Non operational
Table 6: MTBF
Values at specified case temperature
MTBF according to MIL-HDBK-217F, N2
Ground Benign
40°C
3'984'000 h
Ground Fixed
40°C
896'100 h
Ground Mobile
50°C
343'800 h
Edition 4/04.2001
4/6
Board Mountable
Mechanical Data
DC-DC Converters
IMR 3 Series
European
Projection
Dimensions in mm. Tolerances
±0.3
mm unless otherwise specified.
min. 33.8
31.8
2.54
09038
1
mounting space
required
12
Measuring point
of case temperature
T
C
Fig. 4
Case: DIL 24
Weight: 16 g
Safety and Installation Instructions
Installation Instruction
Installation of the DC-DC converters must strictly follow the
national safety regulations in compliance with the enclo-
sure, mounting, creepage, clearance, casualty, markings
and segregation requirements of the end-use application.
Connection to the system shall be made via a printed circuit
board according to:
Mechanical Data
.
The units should be connected to a secondary circuit.
Check for hazardous voltages before altering any connec-
tions.
Ensure that a unit failure (e.g. by an internal short-circuit)
does not result in a hazardous condition. See also:
Safety
min. 3
ø 0.5
Table 7: Pin allocation
Pin
2
3
9
10
11
14
15
16
22
23
Single output unit
Vi–
Vi–
n.c.
n.c.
n.c.
Vo+
n.c.
Vo–
Vi+
Vi+
Dual output unit
Vi–
Vi–
COM
n.c.
Vo–
Vo+
n.c.
COM
Vi+
Vi+
of operator accessible output circuit.
Input Fuse
To prevent excessive current flowing through the input sup-
ply line in case of a short-circuit across the converter input
an external fuse should be installed in a non earthed input
supply line. We recommend a fast acting fuse F2A for
12 IMR 3 types, F1A for 24 IMR 3 types, F0.5A for 40 IMR 3
and 48 IMR 3 types.
Cleaning Agents
In order to avoid possible damage, any penetration of
cleaning fluids is to be prevented, since the power supplies
are not hermetically sealed.
Protection Degree
The protection degree of the DC-DC converters is IP 40.
Table 8: Electric strength test voltages, clearance and
creepage distances
Characteristic
Electric strength
test voltage 1 s
Coupling capacitance
Isulation resistance
at 500 V DC
Input to output
350
500
≈45
>1000
Unit
V
rms
V DC
pF
M
Ω
Edition 4/04.2001
min. 22.3
15.24
20.3
5/6