MPC5606S Microcontroller Data Sheet, Rev. 7
Freescale Semiconductor
61
— Use star routing for the ballast supply from the VDDR supply to avoid ballast startup noise injected to VDDR
supply of the device
— Use LC inductive filtering for ADC, OSC, and PLL supplies if these are generated from common board regulators
Do not:
— Violate injection current limit per IO/All IO pins as per specifications
— Connect sensitive supplies/ground on noisy supplies/ground (that is, ADC, PLL, and OSC)
— Use SMD supply for generation of noise free supply as these are most noisy lines in the system
— Connect different VDD pins (connected together inside the device) to different potentials.
3.5
Thermal characteristics
3.5.1
General notes for specifications at maximum junction temperature
An estimate of the chip junction temperature, TJ, can be obtained from Equation 1: TJ = TA + (RJA PD)
Eqn. 1
where:
TA
= ambient temperature for the package (°C)
Table 17. LQFP thermal characteristics
Symbol
C
Parameter
Conditions
Value
Unit
144-pin 176-pin
RJA
CC D Thermal resistance, junction-to-ambient
natural convection1
1 Junction-to-ambient thermal resistance determined per JEDEC JESD51-3 and JESD51-6. Thermal test board
meets JEDEC specification for this package.
Single layer board—1s
50
43
°C/W
CC
Four layer board—2s2p
41
35
°C/W
RJMA CC D Thermal resistance, junction-to-moving-air
ambient2
@ 200 ft./min., single layer
board—1s
41
35
°C/W
CC
@ 200 ft./min., four layer
board—2s2p
35
30
°C/W
RJB
CC D Thermal resistance, junction-to-board2
2 Junction-to-board thermal resistance determined per JEDEC JESD51-8. Thermal test board meets JEDEC
specification for the specified package.
—29
24
°C/W
RJCtop CC D Thermal resistance, junction-to-case
(top)3
3 Junction-to-case at the top of the package determined using MIL-STD 883 Method 1012.1. The cold plate
temperature is used for the case temperature. Reported value includes the thermal resistance of the interface layer.
—10
9
°C/W
JT
CC D Junction-to-package top thermal
characterization parameter, natural
convection4
4 Thermal characterization parameter indicating the temperature difference between the 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.
—2
2
°C/W