
Analog Integrated Circuit Device Data
Freescale Semiconductor
46
908E625
ADDITIONAL DOCUMENTATION
THERMAL ADDENDUM (REV 2.0)
ADDITIONAL DOCUMENTATION
THERMAL ADDENDUM (REV 2.0)
Introduction
This thermal addendum ia provided as a supplement to the MM908E625
technical data sheet. The addendum provides thermal performance information
that may be critical in the design and development of system applications. All
electrical, application and packaging information is provided in the data sheet.
Package and Thermal Considerations
This MM908E625 is a dual die package. There are two heat sources in the
package independently heating with P
1
and P
2
. This results in two junction
temperatures, T
J1
and T
J2
, and a thermal resistance matrix with R
θ
JA
mn
.
For
m
,
n
= 1, R
θ
JA11
is the thermal resistance from Junction 1 to the reference
temperature while only heat source 1 is heating with P
1
.
For
m
= 1,
n
= 2, R
θ
JA12
is the thermal resistance from Junction 1 to the
reference temperature while heat source 2 is heating with P
2
. This applies to
R
θ
J21
and R
θ
J22
, respectively.
The stated values are solely for a thermal performance comparison of one
package to another in a standardized environment. This methodology is not meant to and will not predict the performance of a
package in an application-specific environment. Stated values were obtained by measurement and simulation according to the
standards listed below.
Standards
Figure 27. Thermal Land Pattern for Direct Thermal
Attachment Per JEDEC JESD51-5Thermal Test Board
54-TERMINAL
SOICW-EP
908E625
DWB SUFFIX
98ARL105910
54-TERMINAL SOICW-EP
Note
For package dimensions, refer to the
908E625 device datasheet.
T
J1
T
J2
=
R
θ
JA11
R
θ
JA21
R
θ
JA12
R
θ
JA22
.
P
1
P
2
Table 14. Thermal Performance Comparison
Thermal
Resistance
1 = Power Chip, 2 = Logic Chip
[
°
C/W]
m
= 1,
n
= 1
m
= 1,
n
= 2
m
= 2,
n
= 1
m
= 2,
n
= 2
R
θ
JA
mn
(1)(2)
23
20
24
R
θ
JB
mn
(2)(3)
9.0
6.0
10
R
θ
JA
mn
(1)(4)
52
47
52
R
θ
JC
mn
(5)
1.0
0
2.0
Notes:
1.
Per JEDEC JESD51-2 at natural convection, still air
condition.
2s2p thermal test board per JEDEC JESD51-7and
JESD51-5.
Per JEDEC JESD51-8, with the board temperature on the
center trace near the power outputs.
Single layer thermal test board per JEDEC JESD51-3 and
JESD51-5.
Thermal resistance between the die junction and the
exposed pad, “infinite” heat sink attached to exposed pad.
2.
3.
4.
5.
1.0
1.0
0.2
0.2
Soldermast
openings
Thermal vias
connected to top
buried plane
54 Terminal SOIC-EP
0.65 mm Pitch
17.9 mm x 7.5 mm Body
10.3 mm x 5.1 mm Exposed Pad
* All measurements
are in millimeters