DS_ DCM04S0A0S12PFA_10022013

E-mail: DCDC@delta.com.tw

http://www.deltaww.com/dcdc

P11

THERMAL CONSIDERATIONS

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

environments

encountered

in

most

electronics

equipment. This type of equipment commonly uses

vertically mounted circuit cards in cabinet racks in which

the power modules are mounted.

The

following

figure

shows

the

wind

tunnel

characterization setup. The power module is mounted

on a test PWB and is vertically positioned within the

wind tunnel.

Thermal Derating

Heat can be removed by increasing airflow over the

module. To enhance system reliability, the power

module should always be operated below the maximum

operating temperature. If the temperature exceeds the

maximum module temperature, reliability of the unit may

be affected.

AIR FLOW

MODULE

PWB

AIR VELOCITY

AND AMBIENT

TEMPERATURE

SURED BELOW

THE MODULE

FANCING PWB

Note: Wind Tunnel Test Setup Figure Dimensions are in millimeters and (Inches)

Figure 36: Wind tunnel test setup

THERMAL CURVES

Figure 37: Temperature measurement location

The allowed maximum hot spot temperature is defined at 107

℃

DCM04S0A0S12 Output Current vs. Ambient Temperature and Air Velocity

@Vin = 5.0V, Vo=3.3V (Airflow From Pin8 To Pin10)

0

3

6

9

12

25

30

35

40

45

50

55

60

65

70

75

80

85

Ambient Temperature (℃)

Output Current(A)

Natural

Convection

Figure 38: Output current vs. ambient temperature and air

velocity@Vin=5V, Vout=3.3V(Either Orientation)

DCM04S0A0S12 Output Current vs. Ambient Temperature and Air Velocity

@Vin = 3.3V, Vo=2.5V (Airflow From Pin8 To Pin10)

0

3

6

9

12

25

30

35

40

45

50

55

60

65

70

75

80

85

Ambient Temperature (℃)

Output Current(A)

Natural

Convection

100LFM

Figure 39: Output current vs. ambient temperature and air

velocity@ Vin=3.3V, Vout=2.5V(Either Orientation)