10K

TRIM

UP/DOWN

TRIM

DOWN

TRIM

UP

PIN 7

PIN 8

PIN 9

-40

-20

0

20

40

60

80

100

120

AMBIENT TEMPERATURE (

°C)

100

75

50

25

0

Power Derating Curve

Without Additional Heatsink

A

B

C

D

71

-40

-20

0

20

40

60

80

100

120

AMBIENT TEMPERATURE (

°C)

100

75

50

25

0

Power Derating Curve

With Side Mounted Heatsink

A

B

C

D

-40

-20

0

20

40

60

80

100

120

AMBIENT TEMPERATURE (

°C)

100

75

50

25

0

Power Derating Curve

With Top Mounted Heatsink

A

B

C

D

Derating Curves

The derating curves shown are based on measurements of actual

power supplies and reflect Artesyn Technologies conservative

design guidelines. Adherence to these guidelines contributes to the

high reliability of our products by restricting the maximum operating

semiconductor junction temperatures to 125°C which is well below

the component manufacturers’ maximum limits.

Key to power derating curves:

A

Natural convection.

B

150 linear feet per minute forced air flow.

C

300 linear feet per minute forced air flow.

D

Maximum case temperature

Heatsink options:

Two heatsink kits are available for the NFC40: top mounted and side

mounted. Each heatsink may be oriented parallel to or perpendicular

to the direction of the pins, thus providing optimum flexibility for

cooling requirements.

Top mounted heatsink

If board area is at a premium in your application then the top

mounted heatsink should be used. This heatsink kit comes com-

plete with screws and is mounted as shown in the diagram over. To

fit the heatsink, place it in the required orientation, and tighten the

four screws. The order number for the top mounted heatsink kit with

Metric screws is: NFC40-HTSK-T. The order number for the top

mounted heatsink kit with Imperial screws is: NFC40-HTSK-T-I.

Side mounted heatsink

With many applications, e.g. rack systems, the profile must be kept

to a minimum. The side mounted heatsink is intended to meet the

requirements of low profile applications. The NFC40 with this

heatsink option is 12.7mm (0.5 inch) high. The kit contains two side

mounted heatsinks, which must be fitted opposite to one another on

the NFC40. The order number for the side mounted heatsink is:

NFC40-HTSK-S

Factory fitted heatsinks

As a further option, Artesyn Technologies offers factory fitted

heatsinks. Simply add the suffix as described by the diagrams

above to the part number: e.g. NFC40-48S12-MY or NFC40-

48S12-1Y for Metric and Imperial screws respectively.

PAGE 144

40 Watt

Wide input DC/DC converters

40W DC/DC

|

DC/DC CONVERTERS

Heatsink Mounting Options

Side Mounted

Top Mounted

76.2

(3.00)

76.2

(3.00)

21.08

(0.83)

21.08

(0.83)

- MX or

-1X

- MY or

-1Y

- MS or

-1S

- ME or

-1E

Output can be externally trimmed

by ±10% using either method shown below.