Bit line precharge in embedded memory
An integrated circuit device includes a first latch having a first input to receive a first predecode value, a second input to receive a first clock signal, and an output to provide a latched first predecode value responsive to an edge event of the first clock signal. The integrated circuit device further includes a memory component. The memory component includes an input to receive the latched first predecode value and the latched second predecode value, a first bit line, and a plurality of word lines coupled to the first bit line. Each word line is associated with a corresponding bit of the latched second predecode value. The integrated circuit device further includes logic having an input to receive the corresponding bit of the latched first predecode value. The logic is to precharge the first bit line directly responsive to only a value at the corresponding bit of the latched first predecode value.
1. A method comprising:
determining a first predecode value based on a first address value;
latching the first predecode value responsive to a first clock signal to provide a latched first predecode value; and
terminating a precharging of a first bit line of a memory component directly responsive to only the latched first predecode value.
2. The method of claim 1 , wherein the memory component comprises a tag array of a cache.
3. The method of claim 2 , further comprising:
determining a tag value associated with the tag array based on the latched first predecode value; and
latching the tag value responsive to a second clock signal.
4. The method of claim 3 , wherein the second clock signal comprises a substantially inverted representation of the first clock signal.
5. The method of claim 1 , further comprising:
determining a second predecode value based on a second address value;
latching the second predecode value responsive to the first clock signal to provide a latched second predecode value; and
terminating a precharging of a second bit line of the memory component directly responsive to only the latched second predecode value, wherein the second bit line of the memory component is associated with the second predecode value.
6. The method of claim 5 , wherein:
the first bit line includes a first local bit line associated with a first memory segment of the memory component, the first memory segment comprising a first plurality of word lines; and
the second bit line includes a second local bit line associated with a second memory segment of the memory component, the second memory segment comprising a second plurality of word lines.
7. The method of claim 6 , further comprising:
terminating a precharging of a global bit line associated with the first bit line and the second bit line directly responsive to only at least one of the first predecode value and the second predecode value.
8. The method of claim 1 , wherein:
the memory component comprises a plurality of memory segments, each memory segment comprising a corresponding plurality of word lines;
each bit of the first predecode value is associated with a corresponding one of the plurality of memory segments; and
wherein a precharging of a bit line of a memory segment is terminated directly responsive to an assertion of the corresponding bit of the first predecode value.
9. A method comprising:
determining, during a first phase of a first clock signal, a first predecode value and a second predecode value based on a first address value and a second address value;
latching the first predecode value and the second predecode value responsive to a first edge event at a termination of the first phase of the first clock signal to provide a latched first predecode value and a latched second predecode value;
terminating a precharging of a first bit line of a first segment of a tag array of a cache directly responsive to only the latched first predecode value, wherein the first segment is selected responsive to an assertion of a corresponding bit of the latched first predecode value;
determining a first tag value at a first word line of the first segment during a first phase of a second clock signal, wherein the first word line is selected responsive to an assertion of a corresponding bit of the latched second predecode value; and
latching the first tag value responsive to a second edge event at a termination of the first phase of the second clock signal.
10. The method of claim 9 , wherein the tag array comprises a global bit line and a plurality of segments including the first segment, each segment comprising a corresponding plurality of word lines and a local bit line coupled to the global bit line, wherein the first bit line of the first segment comprises a local bit line of the first segment.
11. The method of claim 10 , further comprising:
terminating a precharging of the global bit line directly responsive to only the latched first predecode value.
12. The method of claim 9 , further comprising:
determining, during a second phase of the first clock signal subsequent to the first phase, a third predecode value and a fourth predecode value based on a third address value and a fourth address value;
latching the third predecode value and the fourth predecode value responsive to a third edge event at a termination of the second phase of the first clock signal to provide a latched third predecode value and a latched fourth predecode value;
terminating a precharging of a second bit line of a second segment of the tag array directly responsive to only the latched third predecode value, wherein the second segment is selected responsive to an assertion of a corresponding bit of the latched third predecode value;
determining a second tag value at a second word line of the second segment during a second phase of the second clock signal, wherein the second word line is selected responsive to an assertion of a corresponding bit of the latched fourth predecode value; and
latching the second tag value responsive to a fourth edge event at a termination of the second phase of the second clock signal.
13. An integrated circuit device comprising:
a first latch having a first input to receive a first predecode value and a second predecode value, a second input to receive a first clock signal, and an output to provide a latched first predecode value and a latched second predecode value responsive to an edge event of the first clock signal;
a memory component comprising:
an input to receive the latched first predecode value and the latched second predecode value;
a first bit line;
a plurality of word lines coupled to the first bit line, wherein each word line is associated with a corresponding bit of the latched second predecode value; and
logic having an input to receive the corresponding bit of the latched first predecode value, the logic to precharge the first bit line directly responsive to only a value at the corresponding bit of the latched first predecode value.
14. The integrated circuit device of claim 13 , further comprising:
a predecode module comprising a first input to receive a first address value, a second input to receive a second address value and an output coupled to the first input of the latch to provide the first predecode value based on the first address value and the second address value.
15. The integrated circuit device of claim 13 , further comprising:
a second latch having a first input coupled to an output of the memory component, a second input to receive a second clock signal, and an output to provide a latched output value responsive to an edge event of the second clock signal.
16. The integrated circuit device of claim 15 , wherein the memory component comprises a tag array of a cache and the latched output value comprises a latched tag value.
17. The integrated circuit device of claim 13 , wherein the first latch comprises a latch selected from a group consisting of: a dynamic latch, a static latch and a cheater latch.
18. The integrated circuit device of claim 13 , wherein the memory component further comprises:
logic having an input to receive the latched second predecode value, the logic to assert an identified word line of the plurality of word lines responsive to an assertion of the value at a bit of the latched second predecode value corresponding the identified word line.
19. The integrated circuit device of claim 13 , wherein the memory component further comprises:
a second bit line; and
logic having an input to receive the latched first predecode value, the logic to precharge the second bit line directly responsive to the latched first predecode value.
20. The integrated circuit device of claim 13 , wherein the second clock signal comprises a substantially inverted representation of the first clock signal.