FXLS8471Q Datasheet, PDF (69/75 Pages) Freescale Semiconductor, Inc – Linear Accelerometer

12 Package Thermal Characteristics
Table 146. Thermal resistance data
Rating
Description
Symbol
Value
Unit
Junction-to-ambient, natural convection⁽¹⁾⁽²⁾
Single-layer board
163
Junction-to-ambient, natural convection⁽¹⁾⁽³⁾
Four-layer board (two signals, two planes)
R_θJA
70
Junction-to-board⁽⁴⁾
Junction-to-case (top)⁽⁵⁾
Junction-to-package (top)⁽⁶⁾
Natural convection
R_θJB
33
R_θJCTop
84
Ψ_JT
6
°C/W
°C/W
°C/W
°C/W
1. Junction temperature is a function of die size, on-chip power dissipation, package thermal resistance, mounting site (board) temperature,
ambient temperature, air flow, power dissipation of other components on the board, and board thermal resistance.
2. Per JEDEC JESD51-2 with the single-layer board (JESD51-3) horizontal.
3. Per JEDEC JESD51-6 with the board (JESD51-7) horizontal.
4. Thermal resistance between the die and the printed circuit board per JEDEC JESD51-8. Board temperature is measured on the top surface
of the board near the package.
5. Thermal resistance between the die and the case top surface as measured by the cold plate method (MIL SPEC-883 Method 1012.1).
6. Thermal characterization parameter indicating the temperature difference between package top and the junction temperature per JEDEC
JESD51-2. When Greek letters are not available, the thermal characterization parameter is written as Psi-JT.
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Freescale Semiconductor, Inc.
FXLS8471Q
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