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 CURVES
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.
Figure 37:
Temperature measurement location
The allowed maximum hot spot temperature is defined at 107
℃
Output Current(A)
DCM04S0A0S12 Output Current vs. Ambient Temperature and Air Velocity
@Vin = 5.0V, Vo=3.3V (Airflow From Pin8 To Pin10)
12
Natural
Convection
9
6
3
Thermal Derating
0
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.
FANCING PWB
PWB
25
30
35
40
45
50
55
60
65
70
75
80
85
Ambient Temperature (℃)
Figure 38:
Output current vs. ambient temperature and air
velocity@Vin=5V, Vout=3.3V(Either Orientation)
Output Current(A)
DCM04S0A0S12 Output Current vs. Ambient Temperature and Air Velocity
@Vin = 3.3V, Vo=2.5V (Airflow From Pin8 To Pin10)
12
Natural
Convection
9
100LFM
MODULE
6
50.8(2.00")
AIR VELOCITY
AND AMBIENT
TEMPERATURE
SURED BELOW
THE MODULE
AIR FLOW
3
0
25
30
35
40
45
50
55
60
65
70
75
80
85
Ambient Temperature (℃)
Figure 39:
Output current vs. ambient temperature and air
velocity@ Vin=3.3V, Vout=2.5V(Either Orientation)
Note: Wind Tunnel Test Setup Figure Dimensions are in millimeters and (Inches)
Figure 36:
Wind tunnel test setup
DS_ DCM04S0A0S12PFA_10022013
E-mail: DCDC@delta.com.tw
http://www.deltaww.com/dcdc
P11
DELTA [ DELTA ELECTRONICS, INC. ]
