Tri-state content addressable memory

The invention provides a three-state content addressable memory, which is arranged in a stacked memory device and comprises a first storage unit string and a second storage unit string. The first memory cell string is coupled between the matching line and the first source line and receives a plurality of first word line signals. The first memory cell string has a first memory cell string selection switch. The first memory cell string selection switch is controlled by a first search signal. The second memory cell string is coupled between the matching line and the first source line and receives a plurality of second word line signals. The second memory cell string has a second memory cell string selection switch, and the second memory cell string selection switch is controlled by a second search signal. 本发明提供一种三态内容可寻址存储器，设置于堆叠式存储器装置中，包括第一存储单元串以及第二存储单元串。第一存储单元串耦接在匹配线与第一源极线间，并接收多个第一字线信号。第一存储单元串具有第一存储单元串选择开关。第一存储单元串选择开关受控于第一搜索信号。第二存储单元串耦接在匹配线与第一源极线间，并接收多个第二字线信号。第二存储单元串具有第二存储单元串选择开关，第二存储单元串选择开关受控于第二搜索信号。