SRAM:Address Transition Detection (ATD) Circuit for Synchronous Internal Operation [1,10].

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Address Transition Detection (ATD) Circuit for Synchronous Internal Operation [1,10]

The address transition detection (ATD) circuit plays an important role in achieving internal synchronization of operation in SRAM. ATD pulses can be used to generate the different time signals for pulsing word-lines, sensing amplifier, and bit-line equalization. The ATD pulse activating φ(ai) is generated with XOR circuits by detecting “L” to “H” or “H” to “L” transitions of any input address signal ai, as shown in Figure 52.6. All the ATD pulses generated from all the address input transitions are summed up to one pulse, φATD as shown in Figure 52.6. The pulse width of φATD, is controlled by the delay element τ. The pulse width is usually stretched out with a delay circuit and used to reduce or speed up signal propagation in the SRAM.

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