Preliminary Technical Data

WM8788

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PTD, December 2010, Rev 2.2

5

THERMAL PERFORMANCE

Thermal analysis should be performed in the intended application to prevent the WM8788 from

exceeding maximum junction temperature. Several contributing factors affect thermal performance

most notably the physical properties of the mechanical enclosure, location of the device on the PCB

in relation to surrounding components and the number of PCB layers. Connecting the GND pin

through thermal vias and into a large ground plane will aid heat extraction.

Three main heat transfer paths exist to surrounding air as illustrated below in Figure 1:

-

Package top to air (radiation).

-

Package bottom to PCB (radiation).

-

Package pins to PCB (conduction).

Figure 1 Heat Transfer Paths

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-

determined with reference to JEDEC standard JESD51-9.

PARAMETER

SYMBOL

MIN

TYP

MAX

UNIT

Operating temperature range

-40

85

°C

Operating junction temperature

-40

125

°C

Thermal Resistance

95

°C/W

Note:

1.

Junction temperature is a function of ambient temperature and of the device operating conditions. The ambient

temperature limits and junction temperature limits must both be observed.