Thermal Metrology
R
Intel
®
848P Chipset Thermal Design Guide
15
3.2
Thermal Mechanical Test Vehicle
A Thermal Mechanical Test Vehicle (TMTV) is available for early thermal testing prior to the
availability of actual silicon. The TMTV contains a heater die and can be powered up to a desired
power level to simulate the heating of a MCH package. The TMTV also contains daisy chain
functionality and can be used for mechanical testing. The TMTV needs to be surface mounted to a
custom board designed to provide connectivity to the die heater and/or daisy chain depending on the
needs of the user. The package ball connections are provided so the user may design and build a
board to interface with the TMTV. Note that although the TMTV is designed to closely match the
MCH package mechanical form and fit, it is recommended that final validation be performed with
actual production material. The TMTV mechanical features, including die size, ball count, etc., may
not reflect those of the final production package.
3.2.1
TMTV Daisy Chain Operation
The TMTV has alternating pins shorted together on the package to allow daisy chain functionality.
When mounted to a complementary test board, entire rows or the entire package can be shorted
together. Test points on the board can then facilitate the identification of any opens on the mounted
package after any mechanical testing (shock, vibration, temperature cycling, etc.). Figure 4 shows a
schematic of the internal package structures and Figure 5 shows an example of a complementary test
board configuration.
