Memory device, memory package including the same, and memory module including the same

A memory module comprising:

• a first memory package comprising first and second memory devices configured to operate in response to first and second chip select signals, respectively;
• a second memory package comprising third and fourth memory devices configured to operate in response to the first and second chip select signals, respectively;
• and
• a module driver configured to receive a command/address from an external device and to provide the received command/address to the first and second memory packages,
• wherein the first memory device comprises a first buffer unit connected with:
• the external device through a first data line,
• the second memory device through a first memory data line, and
• a first internal circuit of the first memory device through a first internal data line, and
• wherein the third memory device comprises a second buffer unit connected with:
• the external device through a second data line,
• the fourth memory device through a second memory data line, and
• a second internal circuit of the third memory device through a second internal data line.

A memory device comprising:

• a memory cell array comprising a plurality of memory cells;
• a row decoder connected with the memory cell array through word lines, and configured to select one of the word lines corresponding to an address from an external module driver and to control the selected word line;
• a column decoder connected with the memory cell array through bit lines and configured to select some of the bit lines corresponding to the address from the external module driver;
• a sense amplifier and write driver configured to sense voltages of the selected bit lines and to control voltages of the selected bit lines;
• an input/output circuit configured to exchange data with the sense amplifier and write driver;
• and
• a buffer unit connected with:
• an external device of the memory device through a data line,
• a plurality of external memory devices through memory data lines, and
• the input/output circuit through an internal data line.