Semiconductor integrated circuit
A semiconductor memory apparatus includes a buffer control unit configured to deactivate a buffer control signal in response to an auto-refresh start pulse, and activate the buffer control signal in response to an auto-refresh end pulse, a command buffer configured to buffer an external command and output an internal command when the buffer control signal is activated, an address buffer configured to buffer an external address and output an internal address when the buffer control signal is activated, and a clock buffer configured to buffer an external clock and output an internal clock when the buffer control signal is activated.
1. A semiconductor memory apparatus comprising:
a buffer control unit configured to deactivate a buffer control signal in response to an auto-refresh start pulse, and activate the buffer control signal in response to an auto-refresh end pulse;
a command buffer configured to buffer an external command and output an internal command when the buffer control signal is activated;
an address buffer configured to buffer an external address and output an internal address when the buffer control signal is activated; and
a clock buffer configured to buffer an external clock and output an internal clock when the buffer control signal is activated.
2. The semiconductor memory apparatus according to claim 1 , further comprising:
an auto-refresh signal generation unit configured to generate the auto-refresh start pulse when the external command is an auto-refresh command, and generate the auto-refresh end pulse when a predetermined time lapses after the auto-refresh start pulse is generated.
3. The semiconductor memory apparatus according to claim 1 , wherein the buffer control unit is configured to deactivate the buffer control signal when the clock enable signal is deactivated or the auto-refresh start pulse is input, and activate the buffer control signal when the auto-refresh end pulse is input or a clock enable signal is activated.
4. The semiconductor memory apparatus according to claim 3 , wherein the buffer control unit comprises:
an auto-control signal activation maintaining section configured to activate an auto-control signal until the auto-refresh end pulse is input when the auto-refresh start pulse is input; and
a buffer control signal generation section configured to invert the auto-control signal to output the buffer control signal when the clock enable signal is activated, deactivate the buffer control signal when the clock enable signal is deactivated and activate the buffer control signal when the clock enable signal is activated in a case in which the auto-control signal is deactivated.
5. A semiconductor memory apparatus comprising:
a plurality of buffers configured to buffer an external command, an external address, and an external clock to generate an internal command, an internal address, and an internal clock when a buffer control signal is activated;
a plurality of latch units configured to latch the internal command and the internal address in synchronization with the internal clock;
a decoder configured to decode output of the plurality of latch units and generate an auto-refresh activation signal;
an auto-refresh signal generation unit configured to generate an auto-refresh start pulse and an auto-refresh end pulse in response to the auto-refresh activation signal; and
a buffer control unit configured to generate the buffer control signal in response to the auto-refresh start pulse, the auto-refresh end pulse, and a clock enable signal.
6. The semiconductor memory apparatus according to claim 5 , wherein, among the plurality of buffers, a buffer for buffering the external clock to generate the internal clock configured to be deactivated in response to the buffer control signal and lock the internal clock to a specific level.
7. The semiconductor memory apparatus according to claim 6 , wherein the plurality of latch units are configured to be activated when the external clock is output as the internal clock and latch the internal command and the internal address in synchronization with the internal clock, and to be deactivated when the internal clock is locked to the specific level and substantially maintain only a signal latched regardless of the internal command and the internal address.
8. The semiconductor memory apparatus according to claim 5 , wherein the auto-refresh signal generation unit is configured to generate the auto-refresh start pulse when the auto-refresh activation signal is activated, and generate the auto-refresh end pulse when a predetermined time lapses.
9. The semiconductor memory apparatus according to claim 8 , wherein the buffer control unit is configured to deactivate the buffer control signal when the clock enable signal is deactivated or the auto-refresh start pulse is input, and activate the buffer control signal when the auto-refresh end pulse is input or the clock enable signal is activated.
10. The semiconductor memory apparatus according to claim 9 , wherein the buffer control unit comprises:
an auto-control signal activation maintaining section configured to activate an auto-control signal until the auto-refresh end pulse is input when the auto-refresh start pulse is input; and
an buffer control signal generation section configured to invert the auto-control signal to output the buffer control signal when the clock enable signal is activated, deactivate the buffer control signal when the clock enable signal is deactivated and activate the buffer control signal when the clock enable signal is activated in a case in which the auto-control signal is deactivated.
11. A semiconductor memory apparatus comprising:
a buffer control unit configured to deactivate a buffer control signal when an auto-refresh operation starts, activate the buffer control signal when a predetermined time lapses, deactivate the buffer control signal when a clock enable signal is deactivated and a self-refresh operation starts, and activate the buffer control signal when the clock enable signal is activated and the self-refresh operation ends; and
a plurality of buffers configured to be activated in response to the buffer control signal and buffer a command, an address, and a clock, which are provided from outside of the semiconductor memory apparatus.
12. The semiconductor memory apparatus according to claim 11 , further comprising:
an auto-refresh signal generation unit configured to generate an auto-refresh start pulse when an auto-refresh command is input from outside of the semiconductor memory apparatus, and generate an auto-refresh end pulse when a predetermined time lapses after the auto-refresh start pulse is generated.
13. The semiconductor memory apparatus according to claim 12 , wherein the buffer control unit is configured to deactivate the buffer control signal when the clock enable signal is deactivated or the auto-refresh start pulse is input, and activate the buffer control signal when the auto-refresh end pulse is input or the clock enable signal is activated.
14. The semiconductor memory apparatus according to claim 13 , wherein the buffer control unit comprises:
an auto-control signal activation maintaining section configured to activate an auto-control signal until the auto-refresh end pulse is input when the auto-refresh start pulse is input; and
an buffer control signal generation section configured to invert the auto-control signal to output the buffer control signal when the clock enable signal is activated, deactivate the buffer control signal when the clock enable signal is deactivated and activate the buffer control signal when the clock enable signal is activated in a case in which the auto-control signal is deactivated.