公开(公告)号：JPH1070218A

公开(公告)日：1998-03-10

申请号：JP18543297

申请日：1997-07-10

Applicant: IBM

Inventor： BULLER MARVIN LAWRENCE ,  CARPENTER GARY DALE ,  HOANG BINH THAI

IPC: H05K7/20 ,  H01L23/34 ,  H01L23/467

Abstract: PROBLEM TO BE SOLVED: To reduce thermal stress between a printed circuit board and an integrated circuit package by enabling a convection cooling means in response to an indication of high power state and disabling the convection cooling means in response to an indication of low power state. SOLUTION: A ball grid array packaged integrated circuit 2 is fixed to a printed board 1 and an array of solder balls 3 is connected with an integrated circuit chip 6 through a ceramic package base 4. A heat sink assembly 7 is fixed onto the packaged integrated circuit while being fitted tightly to the integrated circuit 6. The heat sink assembly 7 can be subjected to convection cooling with an air flow 8 upon driving a fan 9. A control switch 11 feeds power to the fan 9 and another fan in the housing of a computer system. The switch 11 enables or disables the fan 9 in response a RUN/SLEEP power management signal being fed on a line 12.

公开(公告)号：DE69738187T2

公开(公告)日：2008-07-10

申请号：DE69738187

申请日：1997-07-01

Applicant: IBM

Inventor： BULLER MARVIN LAWRENCE ,  CARPENTER GARY DALE ,  HOANG BINH THAI

IPC: H01L23/34 ,  H01L23/467 ,  H05K7/20

Abstract: Systems and methods for reducing the thermal stresses between an integrated circuit package and a printed circuit board, each having different thermal coefficients of expansion, to minimize thermal fatigue induced by power management cycling. The thermal impedance of the convection cooling system used with the integrated circuit package is switched with the state of the power management signal. A fan on the integrated circuit package heat sink is energized when the integrated circuit is operated in a high power mode and disabled when the integrated circuit is in a low power mode initiated by the power management system. The switching is directly responsive to the power management system and without regard to integrated circuit package temperature. The switching of the fan alters the thermal impedance to reduce the extremes of the temperature excursion and to materially reduce the rate of change of temperature experienced by the integrated circuit package. Relative temperature induced stresses on the connection between the printed circuit board and integrated circuit package are decreased.

公开(公告)号：DE69738187D1

公开(公告)日：2007-11-22

申请号：DE69738187

申请日：1997-07-01

Applicant: IBM

Inventor： BULLER MARVIN LAWRENCE ,  CARPENTER GARY DALE ,  HOANG BINH THAI

IPC: H01L23/467 ,  H01L23/34 ,  H05K7/20

Abstract: Systems and methods for reducing the thermal stresses between an integrated circuit package and a printed circuit board, each having different thermal coefficients of expansion, to minimize thermal fatigue induced by power management cycling. The thermal impedance of the convection cooling system used with the integrated circuit package is switched with the state of the power management signal. A fan on the integrated circuit package heat sink is energized when the integrated circuit is operated in a high power mode and disabled when the integrated circuit is in a low power mode initiated by the power management system. The switching is directly responsive to the power management system and without regard to integrated circuit package temperature. The switching of the fan alters the thermal impedance to reduce the extremes of the temperature excursion and to materially reduce the rate of change of temperature experienced by the integrated circuit package. Relative temperature induced stresses on the connection between the printed circuit board and integrated circuit package are decreased.