®

BCD20007-G Rev AD, 4-Nov-09

Page 8 of 15

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IMX7/IMS7 DC-DC Series Data Sheet

7-Watt DC-DC Converters

Thermal Considerations

If the converter, mounted on a PCB, is located in free, quasi-

stationary air (convection cooling) at the maximum ambient

is operated at nominal input voltage and output power, the

integration into a system, such as input voltage, output

current, airflow, temperature of surrounding components and

is therefore only an indicative value, and under practical

point of case temperature (see Mechanical Data) may under no

circumstances exceed the specified maximum. The installer must

limits stated in the table Temperature specifications.

Fig. 8a

Fig. 8b

×12 V) with both

outputs in parallel

Short-Circuit Behavior

The current limitation shuts down the converter, when a short

circuit is applied to the output. It acts self-protecting, and

automatically recovers after removal of the overload condition.

Output Overvoltage Protection

The outputs are protected against overvoltage by Zener

diodes. In the event of an overvoltage, the converter will shut

down and attempt to restart automatically. The main purpose

of this feature is to protect against possible overvoltage,

which could occur due to a failure in the feedback control

circuit. The converters are not designed to withstand external

overvoltages applied to the outputs.

Connection in Series or Parallel

The outputs of single- or double-output models can be

connected in series without any precautions, taking into

consideration that the output voltage should remain below 60

V for SELV operation.

Both outputs of double-output models can be connected in

parallel without any precautions. Several converters (single-

or double-output models) with equal output voltage can be put

in parallel and will share their output current quite equally.

However, this may cause start-up problems and is only

recommended in applications, where one converter is able to

deliver the full load current, e.g., in true redundant systems.

Fig. 7

Overload switch-off (hiccup mode).

7

8

9

10

11

12

13

0.2

0.4

0.6

0.8

0

05086a

5.5

5.0

4.5

4.0

3.5

3.0

0

0.4

0.8

1.2

1.6

05087a

1.0

0.8

0.6

0.4

0

0.2

20

40

60

80

100

°C

JM017

0.5 m/s = 100 LFM

natural cooling

70

100

t

05041b

0.3 s

overload short-circuit condition

switch-off

0

Fig. 6

Maximum allowed output power versus ambient temperature