Electrical Characteristics
Freescale Semiconductor
33-3
33.3
DC Electrical Specifications
5 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.
The average chip-junction temperature (TJ) in °C can be obtained from:
(1)
Where:
TA
= Ambient Temperature, ×C
QJMA
= Package Thermal Resistance, Junction-to-Ambient, ×C/W
PD
= PINT + PI/O
PINT
= IDD × VDD, Watts - Chip Internal Power
PI/O
= Power Dissipation on Input and Output Pins — User Determined
For most applications PI/O < PINT and can be neglected. An approximate relationship
between PD and TJ (if PI/O is neglected) is:
(2)
Solving equations 1 and 2 for K gives:
K = PD × (TA + 273 × C) + QJMA × PD
2 (3)
where K is a constant pertaining to the particular part. K can be determined from equation
(3) by measuring PD (at equilibrium) for a known TA. Using this value of K, the values of
PD and TJ can be obtained by solving equations (1) and (2) iteratively for any value of TA.
Table 33-3. DC Electrical Specifications1
(VSS = VSSPLL= VSSF = VSSA= 0 VDC)
Characteristic
Symbol
Min
Max
Unit
Input High Voltage
VIH
0.7 x VDD
5.25
V
Input Low Voltage
VIL
VSS – 0.3 0.35 x VDD
V
Input Hysteresis
VHYS
0.06 x
VDD
—mV
Input Leakage Current
Vin = VDD or VSS, Input-only pins
Iin
-1.0
1.0
μA
High Impedance (Off-State) Leakage Current
Vin = VDD or VSS, All input/output and output pins
IOZ
-1.0
1.0
μA
Output High Voltage (All input/output and all output pins)
IOH = –5.0 mA
VOH
VDD - 0.5
__
V
Output Low Voltage (All input/output and all output pins)
IOL = 5.0mA
VOL
__
0.5
V
Weak Internal Pull Up Device Current, tested at VIL Max.
IAPU
-10
-130
μA
Input Capacitance 2
All input-only pins
All input/output (three-state) pins
Cin
—
7
pF
T
J
T
A
P
D
Θ
JMA
×
()
+
=
P
D
KT
J
273
°C
+
()
÷
=
MCF5282 and MCF5216 ColdFire Microcontroller User’s Manual, Rev. 3