Resources Contact Us Home
Method and apparatus for increasing the time available for refresh for 1-t SRAM compatible devices

Image Number 10 for United States Patent #6075740.

A memory system including a DRAM array, a read buffer, a write buffer and an input/output (I/O) interface. The read buffer and write buffer are coupled between the DRAM array and the I/O interface. When an external transaction involves multiple pieces of data in consecutive address locations, such as a burst access, parallel operations are performed in the DRAM array and the I/O interface. In a burst read transaction, all the data in the burst transaction is pre-fetched from the DRAM memory into the read buffer in one memory cycle. After the read data has been pre-fetched, the DRAM array is available for a refresh operation. The DRAM array can therefore be refreshed while the burst read data is sequentially transferred from the read buffer to the I/O interface. In a burst write transaction, multiple burst write data values are written to the write buffer over multiple I/O cycles. This burst write data is not retired to the DRAM array until the next write transaction. At this time, all of the burst write data is simultaneously retired to the DRAM array. As a result, the DRAM array is only engaged in the burst write transaction for one memory cycle. Because the DRAM array is not engaged in the transfer of the new data values from the I/O interface to the write buffer, the DRAM array can be refreshed during one or more of the remaining three I/O cycles.

  Recently Added Patents
JTAG multiplexer with clock/mode input, mode/clock input, and clock output
Video-recording reservation management apparatus, method, program, and system
Control unit including a computing device and a peripheral module which are interconnected via a serial multiwire bus
System and method for detecting an earth ground fault of an external power supply connected to a vehicle
Method for forming ventilation holes in an electrode plate
Method and system for modifying satellite radio program subscriptions in a mobile vehicle
Signal conversion control circuit for touch screen and method thereof
  Randomly Featured Patents
Pharmaceutical agents for the treatment of sickle cell disease
Double-wall balloon catheter for treatment of proliferative tissue
Low profile, secure camper shell latch
Method of racemization of optically active tetrahydrofuran-2-carboxylic acid
Structures, design structures and methods of fabricating global shutter pixel sensor cells
Circuit arrangement for filtering and demodulating a signal frequency-modulator with at least one audio signal
Stent delivery system having stent securement apparatus
Voice activated cellular telephone holder
System and method for managing virtual tree pages
Apparatus and method using activated carbon to purify liquid wastes