40IMX15-03-8RG POWER ONE, 40IMX15-03-8RG Datasheet - Page 11

• Manufacturer Part Number: 40IMX15-03-8RG
• Manufacturer: POWER ONE

Thermal Considerations
If a converter, mounted on a PCB, is located in free, quasi-
stationary air (convection cooling) at the indicated maximum
ambient
specifications) and is operated at its nominal input voltage and
output power, the case temperature measured at the
measuring point of case temperature T
Data) will approach the indicated value T
up phase. However, the relationship between T
depends heavily on the conditions of operation and integration
into a system. The thermal conditions are influenced by input
voltage, output current, airflow, temperature of surrounding
components and surfaces, and the properties of the printed
circuit board. T
Overtemperature Protection
The converters are protected from possible overheating by
means of an internal temperature monitoring circuit. It shuts
down the converter above the internal temperature limit, and
attempts to automatically restart in short intervals. This feature
helps protect against excessive internal temperatures, which
could occur during heavy overload conditions.
Output Overvoltage Protection
The output of single-output models as well as -0503- and -05-
05-models are protected against overvoltage by a second
control loop. In the event of an overvoltage on one of the
outputs, the converter will shut down and attempt to restart in
short intervals.
Doublel-output models (except -0503- and -05-05-models) are
protected against overvoltage by a Zener diode across the
second output. Under worst case conditions the Zener diode
will become a short circuit. Since with double-output models
both outputs track each other, the protection diode is only
provided in one of the outputs. The main purpose of this
feature is to protect against possible overvoltage, which could
occur due to a failure in the control logic. This protection circuit
is not designed to withstand externally applied overvoltages.
Short Circuit Behaviour
The current limit characteristic shuts down the converter,
whenever a short circuit is applied to its output. It acts self-
Fig. 7
Overload switch-off (hiccup mode); typical values
BCD20008-G Rev AA
Caution: The case temperature T
point of case temperature T
circumstances exceed the specified maximum value. The installer
must ensure that under all operating conditions T
the limits stated in the table Temperature specifications.
100
V
70
o
0
[%]
temperature
A max
is therefore only an indicative value.
overload short-circuit condition
switch-off
®
T
C
A max
(see Mechanical Data) may under no
C
(see
measured at the measuring
0.3 s
C max
05041b
table
C
(see Mechanical
C
after the warm-
remains within
t
Temperature
A
and T
IMX15/IMS15/ IMY15 DC-DC Series Data Sheet
Page 11 of 20
C
protecting, and automatically recovers after removal of the
overload condition (hiccup mode).
Parallel and Series Connection
The outputs of one or several single- or double-output models
can be connected in series without any precautions, taking into
consideration that the highest output voltage should remain
below 42 V to ensure that the output remains SELV.
Both outputs of the same converter with equal output voltage
(e.g., 5 V / 5 V) can be put in parallel and will share their output
currents almost equally. Parallel operation of single or double
outputs of two or more converters with the same output voltage
may cause start-up problems at initial start-up. This is only
advisable in applications, where one converter is able to
deliver the full load current as, for example, required in true
redundant systems.
Typical Performance Curves
Fig. 8
V
(110IMY15-05-8R)
Fig. 9
V
both outputs in parallel (110 IMY15-12-12-8)
General conditions:
– T
– Shut-down pin left open-circuit.
– Trim or R input not connected.
o
o
5.5
5.0
4.5
4.0
3.5
3.0
13
12
11
10
V
versus I
V
versus I
9
8
7
A
0
0
= 25
0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 A
0.4 0.8 1.2 1.6 2.0 2.4 2.8 3.2 3.6
o
o
º
C, unless T
(typ.) of double-output models (2 x 12 V), with
(typ) of converters with V
15 -Watt DC-DC Converters
C
is specified.
o
= 5.1 V
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05020a
05166a
4 A
I
o