MCF5235EC Datasheet, PDF (24/46 Pages) Freescale Semiconductor, Inc – Integrated Microprocessor Hardware Specification

Preliminary Electrical Characteristics
Table 7. Absolute Maximum Ratings^{1, 2} (continued)
Rating
Symbol
Value
Unit
Instantaneous Maximum Current
Single pin limit (applies to all pins) ^3,4,5
I_D
25
mA
Operating Temperature Range (Packaged)
T_A
– 40 to 85
°C
(T_L - T_H)
Storage Temperature Range
T_stg
– 65 to 150
°C
1 _{Functional operating conditions are given in DC Electrical Specifications. Absolute Maximum}
Ratings are stress ratings only, and functional operation at the maxima is not guaranteed.
Continued operation at these levels may affect device reliability or cause permanent damage
to the device.
2 _{This device contains circuitry protecting against damage due to high static voltage or}
electrical fields; however, it is advised that normal precautions be taken to avoid application of
any voltages higher than maximum-rated voltages to this high-impedance circuit. Reliability of
operation is enhanced if unused inputs are tied to an appropriate logic voltage level (e.g.,
either V_SS or OV_DD).
3 _{Input must be current limited to the value specified. To determine the value of the required}
current-limiting resistor, calculate resistance values for positive and negative clamp voltages,
then use the larger of the two values.
4 _{All functional non-supply pins are internally clamped to VSS and OVDD.}
5 _{Power supply must maintain regulation within operating OVDD range during instantaneous}
and operating maximum current conditions. If positive injection current (V_in > OV_DD) is greater
than I_DD, the injection current may flow out of OV_DD and could result in external power supply
going out of regulation. Insure external OV_DD load will shunt current greater than maximum
injection current. This will be the greatest risk when the processor is not consuming power
(ex; no clock).Power supply must maintain regulation within operating OV_DD range during
instantaneous and operating maximum current conditions.
7.2 Thermal Characteristics
The below table lists thermal resistance values.
Table 8. Thermal Characteristics
Characteristic
Symbol
256
MAPBGA
196
MAPBGA
160
QFP
Unit
Junction to ambient, natural convection Four layer board (2s2p) θ_JMA
26^1,2
32^1,2
40^1,2 °C/W
Junction to ambient (@200 ft/min)
Four layer board (2s2p) θ_JMA
23^1,2
29^1,2
36^1,2 °C/W
Junction to board
θ_JB
15³
20³
25³ °C/W
Junction to case
θ_JC
10⁴
10⁴
10⁴ °C/W
Junction to top of package
Ψ_jt
2^1,5
2^1,5
2^1,5 °C/W
Maximum operating junction temperature
T_j
102
104
105⁶
o_C
1 _{θJMA and Ψjt parameters are simulated in conformance with EIA/JESD Standard 51-2 for natural convection. Freescale}
recommends the use of θ_JmA and power dissipation specifications in the system design to prevent device junction
temperatures from exceeding the rated specification. System designers should be aware that device junction
temperatures can be significantly influenced by board layout and surrounding devices. Conformance to the device
junction temperature specification can be verified by physical measurement in the customer’s system using the Ψ_jt
parameter, the device power dissipation, and the method described in EIA/JESD Standard 51-2.
2 _{Per JEDEC JESD51-6 with the board horizontal.}
MCF523x Integrated Microprocessor Hardware Specification, Rev. 2
24
Freescale Semiconductor