MC9S12XF512 Datasheet, PDF (1180/1300 Pages) Freescale Semiconductor, Inc – S12X Microcontrollers

Appendix A Electrical Characteristics
Table A-5. Thermal Package Characteristics (MC9S12XF512) ⁽¹⁾
Num C
Rating
Symbol
Min
Typ
Max
Unit
LQFP144
1 D Thermal resistance LQFP144, single sided PCB²
θ_JA
—
—
48
°C/W
2 D Thermal resistance LQFP144, double sided PCB
with 2 internal planes³
θ_JA
—
—
40
°C/W
3 D Junction to Board LQFP 144
4 D Junction to Case LQFP 144⁴
5 D Junction to Package Top LQFP144⁵
θ_JB
—
—
28
°C/W
θ_JC
—
—
9
°C/W
Ψ_JT
—
—
2
°C/W
LQFP112
6 D Thermal resistance LQFP112, single sided PCB⁽²⁾
θ_JA
—
—
49
°C/W
7 D Thermal resistance LQFP112, double sided PCB
with 2 internal planes⁽³⁾
θ_JA
—
—
40
°C/W
8 D Junction to Board LQFP112
9 D Junction to Case LQFP112⁴
10 D Junction to Package Top LQFP112⁵
θ_JB
—
—
28
°C/W
θ_JC
—
—
9
°C/W
Ψ_JT
—
—
2
°C/W
LQFP64
11 D Thermal resistance LQFP 64, single sided PCB²
θ_JA
—
—
62
°C/W
12 D Thermal resistance LQFP 64, double sided PCB
with 2 internal planes³
θ_JA
—
—
44
°C/W
13 D Junction to Board LQFP 64
θ_JB
—
—
27
°C/W
14 D Junction to Case LQFP 64⁽⁴⁾
θ_JC
—
—
10
°C/W
15 D Junction to Package Top LQFP 64⁽⁵⁾
Ψ_JT
—
—
2
°C/W
1. The values for thermal resistance are achieved by package simulations
2. Junction to ambient thermal resistance, θ_JA was simulated to be equivalent to the JEDEC specification JESD51-2 in a
horizontal configuration in natural convection.
3. Junction to ambient thermal resistance, θ_JA was simulated to be equivalent to the JEDEC specification JESD51-7 in a
horizontal configuration in natural convection.
4. Junction to case thermal resistance was simulated to be equivalent to the measured values using the cold plate technique with
the cold plate temperature used as the “case” temperature. This basic cold plate measurement technique is described by MIL-
STD 883D, Method 1012.1. This is the correct thermal metric to use to calculate thermal performance when the package is
being used with a heat sink.
5. Thermal characterization parameter Ψ_JT is the “resistance” from junction to reference point thermocouple on top center of the
case as defined in JESD51-2. Ψ_JT is a useful value to use to estimate junction temperature in a steady state customer
enviroment.
1182
MC9S12XF - Family Reference Manual, Rev.1.18
Freescale Semiconductor