Abstract: The present invention automatically determines the size of an EEPROM in a circuit. A controller is connected to the EEPROM with both a “data to” the EEPROM connection and a “data from” the EEPROM connection. The controller begins to send logical low address bits over the “data to” the EEPROM connection. After each address bit is transmitted, the controller increments the value of a counter. The controller continually monitors the data from the EEPROM connection to determine when the EEPROM has been successfully addressed. Once the EEPROM receives the appropriate number of address bits to fully address the first address location, the EEPROM drives the “data from” connection low. The controller then uses the value of the counter to determine the size of the EEPROM. The controller may either calculate the size of the EEPROM or use the value of the counter in a look-up table.
Type:
Grant
Filed:
December 30, 1999
Date of Patent:
October 2, 2001
Assignee:
Intel Corporation
Inventors:
Richard D. Reohr, Jr., Brian M. Collins
Abstract: A refresh method for a semiconductor memory device reduces the magnitude of the peak current drawn from the power supply. Multiple memory cells coupled to a plurality of word lines are refreshed at one time in order to reduce stand-by power consumption in the refresh mode. Such refresh mode can include automatic refresh or self refresh modes. A plurality of word lines are selected and multiple bit line sense amplifiers corresponding to the selected word lines are activated for the refresh operation. The selected plurality of bit line sense amplifiers are divided into two or more groups and the points in time at which the bit line sense amplifiers are enabled are different for each group. The selected word line and the selected bit line sense amplifiers are then disabled. Thus, the magnitude of the peak current is reduced by dispersing the points in time at which the bit line sense amplifiers are enabled, thereby preventing system misoperation by excessive peak currents in a battery powered system.