Part IV Thermal Characteristics
Table 4-3 shows the thermal characteristics for the MPC850.
Table 4-3. Thermal Characteristics
Characteristic
Thermal resistance for BGA
1
Symbol
θ
JA
θ
JA
θ
JA
Thermal Resistance for BGA (junction-to-case)
1
Value
40
2
31
3
24
4
8
Unit
°
C/W
°
C/W
°
C/W
°
C/W
θ
JC
For more information on the design of thermal vias on multilayer boards and BGA layout considerations in
general, refer to AN-1231/D,
Plastic Ball Grid Array Application Note
available from your local Motorola sales
office.
2
Assumes natural convection and a single layer board (no thermal vias).
3
Assumes natural convection, a multilayer board with thermal vias
4
, 1 watt MPC850 dissipation, and a board
temperature rise of 20°C above ambient.
4
Assumes natural convection, a multilayer board with thermal vias
4
, 1 watt MPC850 dissipation, and a board
temperature rise of 13
°
C above ambient.
T
J
= T
A
+ (P
D
•
θ
JA
)
P
D
= (V
DD
•
I
DD
) + P
I/O
where:
P
I/O
is the power dissipation on pins
Table 4-4 provides power dissipation information.
Table 4-4. Power Dissipation (P
D
)
Characteristic
Power Dissipation
All Revisions
(1:1) Mode
1
2
Frequency (MHz)
33
40
50
Typical
1
TBD
TBD
TBD
Maximum
2
515
590
725
Unit
mW
mW
mW
Typical power dissipation is measured at 3.3V
Maximum power dissipation is measured at 3.65 V
Table 4-5 provides the DC electrical characteristics for the MPC850.
Table 4-5. DC Electrical Specifications
Characteristic
Operating voltage at 40 MHz or less
Operating voltage at 40 MHz or higher
Input high voltage (address bus, data bus, EXTAL, EXTCLK,
and all bus control/status signals)
Input high voltage (all general purpose I/O and peripheral pins)
Symbol
VDDH, VDDL,
KAPWR, VDDSYN
VDDH, VDDL,
KAPWR, VDDSYN
VIH
VIH
Min
3.0
3.135
2.0
2.0
Max
3.6
3.465
3.6
5.5
Unit
V
V
V
V
MOTOROLA
MPC850 (Rev. A/B/C) Hardware Specifications
9
MOTOROLA [ MOTOROLA, INC ]
