Refresh control circuit and method for semiconductor memory apparatus

摘要

A refresh control circuit of a semiconductor memory apparatus includes: a variable oscillator configured to generate a room-temperature oscillation signal and a limit-temperature oscillation signal in response to a temperature state signal; a cycle selector configured to selectively output the room temperature oscillation signal and the limit-temperature oscillation signal as a variable oscillation signal in response to the temperature state signal; a refresh signal generator configured to generate a refresh signal in response to the variable oscillation signal and a fixed oscillation signal; and a temperature state detector configured to generate the temperature state signal by detecting current temperature in response to the room-temperature oscillation signal and the fixed oscillation signal.