Delta Electronics H48SV manual Thermal Considerations, Thermal Curves, Thermal Testing Setup

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THERMAL CONSIDERATIONS

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. The space between the neighboring PWB and the top of the power module is constantly kept at 6.35mm (0.25’’).

Thermal Derating

Heat can be removed by increasing airflow over the module. The module’s maximum case temperature is +105°C. 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.

THERMAL CURVES

FACING PWB

PWB

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

MODULE

Figure 21: Hot spot temperature measured point

 

 

 

 

*The allowed maximum hot spot temperature is defined at 105

 

 

 

 

 

 

*The over-temperature shutdown is 117

 

 

 

 

 

 

 

 

 

 

H48SV05030(Standard) Output Current vs. Ambient Temperature and Air Velocity

 

 

 

 

Output Current(A)

 

@ Vin = 48V (Either Orientation, no Heat sink)

 

 

 

 

 

 

35

 

 

 

 

 

 

 

 

 

 

 

 

 

AIR VELOCITY

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

AND AMBIENT

 

30

 

 

 

 

 

 

 

 

 

 

 

 

 

TEMPERATURE

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

MEASURED BELOW

50.8 (2.0”)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

THE MODULE

25

 

 

 

 

 

 

 

 

 

 

 

 

 

AIR FLOW

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

20

Natural

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Convection

 

 

 

 

 

 

 

 

 

 

 

 

 

 

15

100LFM

 

 

 

 

 

 

 

 

 

 

 

 

 

 

200LFM

 

 

 

 

 

 

 

 

 

 

 

 

 

12.7 (0.5”)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

10

300LFM

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

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

 

400LFM

 

 

 

 

 

 

 

 

 

 

 

 

 

 

5

500LFM

 

 

 

 

 

 

 

 

 

 

 

 

Figure 20: Wind Tunnel Test Setup

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

600LFM

 

 

 

 

 

 

 

 

 

 

 

 

 

 

0

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

20

25

30

35

40

45

50

55

60

65

70

75

80

85

 

 

 

 

 

 

 

 

 

 

 

 

 

Ambient Temperature ()

Figure 22: Output current vs. ambient temperature and air velocity (Vin=48V, transverse Orientation, no heat sink)

DS_H48SV05030_08102007

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Image 11
Contents DATASHEET DSH48SV0503004262006 FEATURESOPTIONS APPLICATIONSDYNAMIC CHARACTERISTICS TECHNICAL SPECIFICATIONSINPUT CHARACTERISTICS OUTPUT CHARACTERISTICSELECTRICAL CHARACTERISTICS CURVES For Positive Remote On/Off Logic For Negative Remote On/Off LogicFigure 8 Output voltage response to step-change in load current 50%-75%-50% of Imax dI/dt = 0.1A/µs.Vin=48V. Load cap 10µF, tantalum capacitor and 1µF ceramic capacitor. Top trace Vout 100mV/div, Bottom trace Iout 10A/div. Scope measurement should be made using a BNC cable length shorter than 20 inch. Position the load between 51 mm and 76 mm 2 inches and 3 inches from the module Figure 13 Output voltage noise and ripple measurement test setup Figure 14 Output voltage ripple at nominal input voltage Vin=48V and rated load current Io=30A 20 mV/div. Load capacitance 1µF ceramic capacitor and 10µF tantalum capacitor. Bandwidth 20 MHz. Scope measurement should be made using a BNC cable length shorter than 20 inches. Position the load between 51 mm and 76 mm 2 inches and 3 inches from the module Input Source Impedance Safety ConsiderationsSoldering and Cleaning Considerations DESIGN CONSIDERATIONSOver-Temperature Protection FEATURES DESCRIPTIONSOver-Current Protection Over-Voltage ProtectionOutput Voltage Adjustment TRIM FEATURES DESCRIPTIONS CONThermal Derating Thermal Testing SetupTHERMAL CONSIDERATIONS THERMAL CURVESFunction Pin SpecificationMECHANICAL DRAWING NameEFF @ 100% LOAD WARRANTYPART NUMBERING SYSTEM MODEL LIST