TDK iQA Series manual Thermal Management, Thermal Derating

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Advance Data Sheet: Dualeta™ iQA Series – Dual Quarter Brick

Thermal Management:

An important part of the overall system design process is thermal management; thermal design must be considered at all levels to ensure good reliability and lifetime of the final system. Superior thermal design and ability to operate in severe application environments are key elements of a robust, reliable power module.

direction can have a significant impact on the module’s thermal performance.

Thermal Derating:

For proper application of the power module in a given thermal environment, output current derating curves are provided as a design guideline in the

Adjacent PCB

A finite amount of heat must be dissipated from the power module to the surrounding environment. This heat is transferred by the three modes of heat transfer: convection, conduction and radiation. While all three modes of heat transfer are present in every application, convection is the dominant mode of heat transfer in most applications. However, to ensure adequate cooling and proper operation, all three modes should be considered in a final system configuration.

The open frame design of the power module provides an air path to individual components. This air path improves heat conduction and convection to the surrounding environment, which reduces areas of heat concentration and resulting hot spots.

Module

Centerline

76 (3.0)

AIRFLOW

A

 

 

12.7

 

 

I

 

 

(0.50)

R

 

 

 

F

 

 

 

L

 

 

 

O

 

 

 

W

 

 

 

 

 

 

 

 

 

 

 

Test Setup

The thermal performance data of the power module is based upon measurements obtained from a wind tunnel test with the setup shown below. This thermal test setup replicates the typical thermal environments encountered in most modern electronic systems with distributed power architectures. The electronic equipment in optical networking, telecom, wireless and advanced computer systems operate in similar environments and utilize vertically mounted PCBs or circuit cards in cabinet racks.

The power module, as shown in the figure, is mounted on a printed circuit board (PCB) and is vertically oriented within the wind tunnel. The cross section of the airflow passage is rectangular. The spacing between the top of the module or heatsink (where applicable) and a parallel facing PCB is kept at a constant (0.5 in). The power module orientation with respect to the airflow

Air Velocity and Ambient

Air Passage

Temperature Measurement

Centerline

Location

 

Wind Tunnel Test Setup

Dimensions are in millimeters and (inches).

Thermal Performance section. The module temperature should be measured in the final system configuration to ensure proper thermal management of the power module. In all conditions, the power module should be operated below the maximum operating temperature shown on the de-rating curve. For improved design margins and enhanced system reliability, the power module may be operated at temperatures below the maximum rated operating temperature.

Heat transfer by convection can be enhanced by increasing the airflow rate that the power module experiences. The maximum output current of the power module is a function of ambient temperature (TAMB) and airflow rate as shown in the

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iQAFullDatasheet080505 2.doc 8/3/2006

 

 

 

 

 

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Contents Features OptionsOrdering information Product OfferingMechanical Specification Recommended Hole Pattern top view Pin AssignmentInput Characteristics Absolute Maximum RatingsElectrical Data IQA48015A033M 3.3V/2.5V, 15A OutputElectrical Characteristics Typical Vo1 load transient response. Io1 step from 3.75A Trim up tracking trim option IQA48015A050M 5V/3.3V, 15A Output 10/19 11/19 12/19 Thermal Performance Thermal Management Thermal DeratingOperating Information Dual independent Trim Optional Tracking Trim Reliability WarrantyInput/Output Ripple and Noise Measurements QualitySafety Considerations Support@tdkinnoveta.com