Air Cooled Memory With Fan Speed Varied With Current Supplied to Memory
Original Publication Date: 1986-Sep-01
Included in the Prior Art Database: 2005-Mar-09
Semiconductor memory chops are arranged to be cooled by air from fans that are driven by variable speed motors. In a memory in which a bit is represented by the presence or absence of a charge on a capacitor, the heat load varies with the bit pattern that is stored in the memory. The heat is produced by ohmic heating associated with the current supplied to the memory, and it is directly proportional to the current because the voltage is constant. In this system, the fan motors are varied in speed from a current signal. When the memory is operating at maximum power, the fans run at their maximum speed. When the memory is operating at lower power, the fan motors are slowed. Running the fans slower reduces noise and increases the life of the motor.