Sense amplifier enable signal generator for semiconductor memory device
A semiconductor memory device includes a bit line sense amplifier, a sense amplifier enable signal generator, a power line driver, and a driver controller. The bit line sense amplifier senses and amplifies data carried on a bit line. The sense amplifier enable signal generator generates a sense amplifier enable signal in response to an active command signal and a precharge command signal. Activation points of times of the sense amplifier enable signal corresponding to the active command signal are multiplexed depending on input/output bandwidth option information. The power line driver drives a pull-up power line and a pull-down power line of the bit line sense amplifier. The driver controller controls the power line driver in response to the sense amplifier enable signal.
1. A semiconductor memory device, comprising:
a bit line sense amplifier for sensing and amplifying data carried on a bit line;
a sense amplifier enable signal generator for generating a sense amplifier enable signal in response to an active command signal and a precharge command signal, wherein activation point the sense amplifier enable signal is multiplexed depending on input/output bandwidth option information;
a power line driver for driving a pull-up power line and a pull-down power line of the bit line sense amplifier; and
a driver controller for controlling the power line driver in response to the sense amplifier enable signal.
2. The semiconductor memory device as recited in claim 1 , wherein the sense amplifier enable signal generator includes:
a default delay circuit for delaying the active command signal by a predetermined sensing delay time;
an auxiliary delay circuit for selectively delaying an output signal of the default delay circuit based on the input/output bandwidth option information; and
a sense amplifier enable signal output circuit for outputting the sense amplifier enable signal in response to an output signal of the auxiliary delay circuit and the precharge command signal.
3. The semiconductor memory device as recited in claim 2 , wherein the auxiliary delay circuit selectively delays an output signal of the default delay circuit by a relatively large time period if the input/output bandwidth information has a relatively large value, and selectively delays an output signal of the default delay circuit by a relatively small time period if the input/output bandwidth information has a relatively small value.
4. The semiconductor memory device as recited in claim 2 , wherein the auxiliary delay circuit includes:
a first delay selector for selectively delaying an output signal of the default delay circuit by a first predetermined time period in response to a first input/output bandwidth option information signal; and
a second delay selector for selectively delaying an output signal of the first delay selector by a second predetermined time period in response to a second input/output bandwidth option information signal.
5. The semiconductor memory device as recited in claim 4 , wherein the first delay selector includes:
a delay circuit for delaying the output signal of the default delay circuit by the first predetermined time period;
a first inverter for inverting an output signal of the delay circuit;
a first NAND gate for NAND-operating on an output signal of the first inverter and the first input/output bandwidth option information signal;
a second NAND gate for NAND-operating on an output signal of the default delay circuit and an output signal of the first NAND gate; and
a second inverter for inverting an output signal of the second NAND gate.
6. The semiconductor memory device as recited in claim 4 , wherein the second delay selector includes:
a delay circuit for delaying the output signal of the first delay selector by the second predetermined time period;
a first inverter for inverting an output signal of the delay circuit;
a first NAND gate for NAND-operating on an output signal of the first inverter and the second input/output bandwidth option information signal;
a second NAND gate for NAND-operating on an output signal of the first delay selector and an output signal of the first NAND gate; and
a second inverter for inverting an output signal of the second NAND gate.
7. A sense amplifier enable signal generator for a semiconductor memory device, comprising:
a default delay circuit for delaying an active command signal by a predetermined sensing delay;
an auxiliary delay circuit for selectively delaying an output signal of the default delay circuit based on input/output bandwidth option information; and
a sense amplifier enable signal output circuit for outputting a sense amplifier enable signal in response to an output signal of the auxiliary delay circuit and a precharge command signal.
8. The sense amplifier enable signal generator as recited in claim 7 , wherein the auxiliary delay circuit selectively delays an output signal of the default delay circuit by a relatively large time period if the input/output bandwidth information has a relatively large value, and selectively delays an output signal of the default delay circuit by a relatively small time period if the input/output bandwidth information has a relatively small value.
9. The sense amplifier enable signal generator as recited in claim 7 , wherein the auxiliary delay circuit includes:
a first delay selector for selectively delaying the output signal of the default delay circuit by a first predetermined time period in response to a first input/output bandwidth option information signal; and
a second delay selector for selectively delaying an output signal of the first delay selector by a second predetermined time period in response to a second input/output bandwidth option information signal.
10. The sense amplifier enable signal generator as recited in claim 9 , wherein the first delay selector includes:
a delay circuit for delaying the output signal of the default delay circuit by the first predetermined time period;
a first inverter for inverting an output signal of the delay circuit;
a first NAND gate for NAND-operating on an output signal of the first inverter and the first input/output bandwidth option information signal;
a second NAND gate for NAND-operating on an output signal of the default delay circuit and an output signal of the first NAND gate; and
a second inverter for inverting an output signal of the second NAND gate.
11. The sense amplifier enable signal generator as recited in claim 9 , wherein the second delay selector includes:
a delay circuit for delaying the output signal of the first delay selector by the second predetermined time period;
a first inverter for inverting an output signal of the delay circuit;
a first NAND gate for NAND-operating on an output signal of the first inverter and the second input/output bandwidth option information signal;
a second NAND gate for NAND-operating on an output signal of the first delay selector and an output signal of the first NAND gate; and
a second inverter for inverting an output signal of the second NAND gate.