T-8110L AGERE [Agere Systems], T-8110L Datasheet - Page 127

• Manufacturer Part Number: T-8110L
• Manufacturer: AGERE [Agere Systems]

February 2004
Agere Systems Inc.
13 Electrical Characteristics
13.3 Thermal Parameters (Definitions and Values)
die out of the package through the leads or balls by lowering the board temperature and insulating the package top.
This is done using a special fixture, which keeps the board in contact with a water chilled copper slug around the
perimeter of the package while insulating the package top.
junction temperature while the part is operating in their system. It is not considered a true thermal resistance.
is calculated using the following formula:
Table 105. Thermal Parameter Values
13.4 Reliability
Product reliability can be calculated as the probability that the product will perform under normal operating condi-
tions for a set period of time. Factors influencing the reliability of a product cover a range of variables, including de-
sign and manufacturing. The failure rate of a product is given as the number of units failing per unit time. This failure
rate is known as FIT, which is as follows:
1 FIT = 1 Failure/1x10e
Another unit used for failure rate is known as MTBF, which is 1/FIT. Many assumptions are made when calculating
the failure rate for a product, such as the average junction temperature and activation energy. The assumptions
made for calculating FIT and MTBF are shown in Table 106:
Table 106. Reliability Data
JB
JB
JB
JT
JT
JT
Junction Temperature
JA
JMA
JMA
JC
JB
JT
—Junction to Board Thermal Resistance
is the thermal resistance from junction to board. This number is determined by forcing the heat generated in the
= (T
correlates the junction temperature to the case temperature. It is generally used by the customer to infer the
= (T
(1 m/s)
(2.5 m/s)
J
J
– T
– T
55 °C
B
C
)/P
)/P
Parameter
9
hours.
FIT (Per 10e
(continued)
9
10
Device Hours
22
19
17.5
20
TBD
1.0
JB
Ambassador T8110L H.100/H.110 Switch
(continued)
is calculated using the following formula:
1.0e
MTBF
Temperature °C/Watt
8
hours
Activation Energy
.7eV
127
JT