Delta Electronics 6A Series manual Thermal Consideration, Thermal Testing Setup, Thermal Derating

THERMAL CONSIDERATION THERMAL CURVES (VERTICAL)

Thermal management is an important part of the system design. To ensure proper, reliable operation, sufficient cooling of the power module is needed over the entire temperature range of the module. Convection cooling is usually the dominant mode of heat transfer.

Hence, the choice of equipment to characterize the thermal performance of the power module is a wind tunnel.

Thermal Testing Setup

Delta’s DC/DC power modules are characterized in

heated vertical wind tunnels that simulate the thermal

Figure 26: Temperature measurement location* The allowed

environments

encountered

in

most

electronics

equipment. This type of equipment commonly uses

maximum hot spot temperature is defined at 113℃

vertically mounted circuit cards in cabinet racks in which

Output Current (A)

NE12S0A0V06(standard)

Output Current vs. Ambient Temperature and Air Velocity

the power modules are mounted.

@Vin=12V Vout=0.9V (Either Orientation)

6

The following

figure

shows

the

wind

tunnel

Convection

Natural

characterization setup. The power module is mounted

5

4

on a test PWB and is vertically positioned within the

100LFM

wind tunnel. The space between the neighboring PWB

200LFM

and the top of the power module is constantly kept at

3

300LFM

6.35mm (0.25’’).

400LFM

2

Thermal Derating

1

Heat can be removed by increasing airflow over the

0

module. To enhance

system

reliability, the

power

Ambient Temperature (℃)

25

30

35

40

45

50

55

60

65

70

75

80

85

module should always be operated below the maximum

operating temperature. If the temperature exceeds the

Figure 27: Output current vs. ambient temperature and air

maximum module temperature, reliability of the unit may

velocity @Vin=12V, Vout=0.9V (Either Orientation)

be affected.

FACING PWB

AIR VELOCITY

AND AMBIENT

TEMPERATURE

MEASURED BELOW

THE MODULE

AIR FLOW

PWB	Output Current (A)		NE12S0A0V06(standard)			Output Current vs. Ambient Temperature and Air Velocity
					@Vin=12V Vout=2.5V (Either Orientation)
	6
MODULE							Natural
	5						Convection
									100LFM
									200LFM
	4
									300LFM
	3								400LFM
50.8 (2.0”)	2								500LFM
	1
11 (0.43”)	0
22 (0.87”)	25	30	35	40	45	50	55	60	65	70	75	80	85
											Ambient Temperature (℃)

Note: Wind tunnel test setup figure dimensions are in	Figure 28: Output current vs. ambient temperature and air
	velocity @Vin=12V, Vout=2.5V (Either Orientation)
millimeters and (Inches)
Figure 25: Wind tunnel test setup
DS_NE12S06A_06302008	9