Extendable output power characterisation of 48IMS30-0302-9G

under forced air condition

20

22

24

26

28

30

32

0

100

200

300

400

500

600

700

800

Air-Flow (LFM)

Table 6: Typical values for undervoltage lockout (PUL)

settings.

48 IMS 30

31

50

34

29

36

20

38

15

40

Auxiliary Functions

Shut Down Function

The outputs of the converters may be enabled or disabled

by means of a logic signal (TTL, CMOS, etc.) applied to the

shut down pin. If the shut down function is not required then

pin should be left open-circuit.

Converter operating:

2.0...5.0 V

Converter shut down:

–1...0.7 V

The shut down pin can also be used as a programmable

undervoltage lockout. The undervoltage lockout values for

the 48 IMS30 series is 31 V with a 0.5V hysteresis window

which can be trimmed up by means of an external resistor

connected between the SD/PUL pin and Vi– pin.

Adjustable Output Voltage

As a standard feature, the IMS 30 units offer adjustable

output voltage by using the secondary referenced control

Trim. If the control input is left open-circuit the output volt-

age is set to

sible by means of an external resistor

tween the Trim pin and the either Vo+ or Vo–.

Vo+

Vi+

Vi–

Vo–

06133

R

ext

SD/PUL

Fig. 8

Shut down (SD) and undervoltage lockout (PUL) function.

Vo+

Vi+

Vi–

Vo–

06134

Trim

R

ext 1

R

ext 2

Fig. 9

Output voltage Trim.

[k]

[k]

3.3

2.97

8

3.63

5

Synchronisation

The IMS 30 provides a bi-directional synchronisation func-

tion to synchronise several IMS 30 units operated in parallel

connection. When the W pins (SYNC) are connected to-

gether, the converters will lock to the highest switching fre-

quency. The faster controller becomes the master, produc-

ing a 4.3 V, 200 ns pulse train. Only one, the highest fre-

quency SYNC signal, will appear on the Sync line.

6/11

Thermal Considerations

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

stationary air (convection cooling) at the indicated maxi-

mum ambient temperature

specifications) and is operated at its nominal input voltage

and output power, the case temperature

warm-up phase. However, the relationship between

gration into a system. The thermal conditions are influenced

by input voltage, output current, airflow, temperature of sur-

rounding components and surfaces and the properties of

the printed circuit board.

tive value and under practical operating conditions, the ad-

missible ambient temperature

than this value.

Caution: The case temperature

cal Data) must under no circumstances exceed the

specified maximum value. The installer must ensure that

under all operating conditions

its stated in the table:

Temperature specifications.

Short Circuit Behaviour

The current limit characteristic shuts down the converter

whenever a short circuit or an overload is applied to its out-

put. It acts self-protecting and automatically recovers after

removal of the overload condition (hiccup mode).

Overtemperature Protection

The converters are protected from possible overheating by

means of an internal non latching temperature monitoring

circuit. It shuts down the unit above the internal tempera-

ture limit and attempts to automatically restart in short peri-

ods. This feature prevents excessive internal temperature

excursion which could occur in heavy overload conditions.

Typical Performance Curves

General conditions :

circuit. Trim input not connected.

Fig. 5

Overload switch off (hiccup mode), typical values.

100

t [ms]

05162

100

10

0