Freescale Semiconductor *KE02 Series, Technical Data Manual

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





 
t
ICPW
FTMCHn
t
ICPW
FTMCHn
Figure 12. Timer input capture pulse
Thermal specifications
5.3.1 Thermal operating requirements
Table 9. Thermal operating requirements
Symbol Description Min. Max. Unit Notes
T
J
Die junction temperature –40 125 °C
T
A
Ambient temperature –40 105 °C 1
1. Maximum T
A
can be exceeded only if the user ensures that T
J
does not exceed maximum T
J
. The simplest method to
determine T
J
is: T
J
= T
A
+
θ
JA
x chip power dissipation
5.3.2 Thermal characteristics
This section provides information about operating temperature range, power dissipation,
and package thermal resistance. Power dissipation on I/O pins is usually small compared
to the power dissipation in on-chip logic and voltage regulator circuits, and it is user-
determined rather than being controlled by the MCU design. To take P
I/O
into account in
power calculations, determine the difference between actual pin voltage and V
SS
or V
DD
and multiply by the pin current for each I/O pin. Except in cases of unusually high pin
current (heavy loads), the difference between pin voltage and V
SS
or V
DD
will be very
small.
Table 10. Thermal attributes
Board type Symbol Description 64
LQFP
64 QFP 44
LQFP
32
LQFP
Unit Notes
Single-layer (1S) R
θ
JA
Thermal resistance, junction
to ambient (natural
convection) 71 61 75 86 °C/W 1 , 2
Four-layer (2s2p) R
θ
JA
Thermal resistance, junction
to ambient (natural
convection) 53 47 53 57 °C/W 1 , 3
Table continues on the next page...
5.3
Thermal specifications
KE02 Sub-Family Data Sheet, Rev4, 10/2014.
18 Freescale Semiconductor, Inc.