Current Sharing Thermal Derating Curves

20

60

70

90

30

40

50

80

0

80

60

40

20

I

O

– Ouput Current – A

V

I

= 12 V

V

O

= 3.3 V

400 LFM

200 LFM

100 LFM

400 LFM

200 LFM

100 LFM

Nat conv

Natural

Convection

20

60

70

90

80

0

80

60

40

20

I

O

– Ouput Current – A

400 LFM

200 LFM

100 LFM

30

40

50

V

I

= 12 V

V

O

= 5 V

400 LFM

200 LFM

100 LFM

Nat conv

Natural

Convection

PTH08T255W

The temperature derating curves in Figure 20 and Figure 21 represent the conditions at which internal

components are at or below the manufacturer's maximum operating temperatures. Derating limits apply to two

PTH08T255W modules soldered directly to a 100 mm × 200 mm double-sided PCB with 2 oz. copper and the

direction of airflow from pins 10 to pins 22. For surface mount packages (AS and AZ suffix), multiple vias must

be utilized. Please refer to the mechanical specification for more information.

AMBIENT TEMPERATURE

AMBIENT TEMPERATURE

vs

vs

OUTPUT CURRENT

OUTPUT CURRENT

Figure 20.

Figure 21.

26

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Product Folder Link(s): PTH08T255W