Semiconductor memory device, memory system including same, and method of controlling same

A semiconductor memory device, a memory system including the same, and a method of controlling the same are provided. The semiconductor memory device includes a plurality of input-output pins configured to communicate with a memory controller, a command control logic, a temperature measurement circuit, and an operation limit controller. The command control logic controls an operation of the semiconductor memory device based on a command signal and a control signal transferred from the memory controller through a control pin among the plurality of input-output pins. The temperature measurement circuit measures an operating temperature of the semiconductor memory device to generate a temperature code corresponding to the operating temperature. When it is determined that the operating temperature exceeds a risk temperature based on the temperature code, the operation limiting controller controls an internal operation of the semiconductor memory device regardless of the command signal and the control signal trans