Charge sharing in a TCAM array
A memory cell includes a storage capacitor, a read line, and a storage transistor, where the storage transistor is connected to the read line and is subject to activation by a charge in the storage capacitor. An in-memory processor includes a memory array which stores data, and an activation unit to activate at least two cells in a column of the memory array at generally the same time, thereby to generate a Boolean function output of the data of the at least two cells, wherein each of the at least two cells includes at least a storage capacitor, a storage transistor and a read line, where the storage transistor is connected to the read line and subject to activation by a charge in the storage capacitor.
1. A content addressable memory (CAM) unit comprising:
a memory array of storage cells located at the intersection of word lines defining rows and read lines defining columns, each of said storage cells comprising at least a storage capacitor, a storage transistor and a read line, wherein said storage transistor is connected to said read line and subject to activation by a charge in said storage capacitor;
a controller to provide an indication to a multiple row decoder to activate at a same time more than one word line in said memory array as a function of an input pattern to be matched;
said multiple row decoder to activate said more than one word line responsive to said indication; and
a CAM output unit to output a result associated with which columns of storage cells comprise data matching said pattern,
wherein said CAM output unit comprises a write unit to write said result into said memory array.
2. The CAM unit according to claim 1 and wherein said memory array of storage cells comprises 3T DRAM cells.
3. The CAM unit according to claim 1 and wherein said memory array of storage cells comprises one of the following type of memory cells: SRAM cells, DRAM cells, and non-destructive cells.
4. The CAM unit according to claim 1 and wherein said memory array of storage cells provides a determinate result when multiple cells are read together.
5. The CAM unit according to claim 1 and wherein said memory array has at least a first portion to store data and at least a second portion into which said CAM output unit writes.
6. The CAM unit according to claim 1 and wherein said CAM unit is a ternary CAM unit.
7. The CAM unit according to claim 1 and wherein said CAM unit is a quadrary CAM unit.