Abstract:
Clock tree design methods for ultra-wide voltage range circuits are disclosed. In one aspect, place and route software creates an integrated circuit (IC) in an optimal configuration at a first voltage condition. A first clock tree is created as part of the place and route process. Clock skew for the first clock tree is evaluated and minimized through insertion of bypassable delay elements. The delay elements are then removed from the wiring routing diagram. A second voltage condition is identified, and clock tree generation software is allowed to optimize the wiring routing diagram for the second voltage condition. The second clock tree generation software may insert more bypassable delay elements into the wiring routing diagram that allow clock skew optimization at the second voltage condition. The initial bypassable delay elements are then reinserted into the wiring routing diagram and a finished IC is established.
Abstract:
Write-assist circuits for memory bit cells (“bit cells”) employing a P-type Field-Effect transistor (PFET) write port(s) are disclosed. Related methods and systems are also disclosed. It has been observed that as node technology is scaled down in size, PFET drive current (i.e., drive strength) exceeds N-type Field-Effect transistor (NFET) drive current for like-dimensioned FETs. In this regard, in one aspect, it is desired to provide bit cells having PFET write ports, as opposed to NFET write ports, to reduce memory write times to the bit cells, and thus improve memory performance. To mitigate a write contention that could otherwise occur when writing data to bit cells, a write-assist circuit provided in the form of positive bitline boost circuit can be employed to strengthen a PFET access transistor in a memory bit cell having a PFET write port(s).
Abstract:
Write-assist circuits for memory bit cells (“bit cells”) employing a P-type Field-Effect transistor (PFET) write port(s) are disclosed. Related methods and systems are also disclosed. It has been observed that as node technology is scaled down in size, PFET drive current (i.e., drive strength) exceeds N-type Field-Effect transistor (NFET) drive current for like-dimensioned FETs. In this regard, in one aspect, it is desired to provide bit cells having PFET write ports, as opposed to NFET write ports, to reduce memory write times to the bit cells, and thus improve memory performance. To mitigate a write contention that could otherwise occur when writing data to bit cells, a write-assist circuit provided in the form of negative wordline boost circuit can be employed to strengthen a PFET access transistor in a memory bit cell having a PFET write port(s).
Abstract:
P-type Field-effect Transistor (PFET)-based sense amplifiers for reading PFET pass-gate memory bit cells (“bit cells”) are disclosed. Related methods and systems are also disclosed. Sense amplifiers are provided in a memory system to sense bit line voltage(s) of the bit cells for reading the data stored in the bit cells. It has been observed that as node technology is scaled down in size, PFET drive current (i.e., drive strength) exceeds N-type Field-effect Transistor (NFET) drive current due for like-dimensioned FETs. In this regard, in one aspect, PFET-based sense amplifiers are provided in a memory system to increase memory read times to the bit cells, and thus improve memory read performance.
Abstract:
A register file circuit according to some examples of the disclosure may include a memory cell, a header transistor circuit, and a driver circuit. The header transistor circuit may include one or more PFET headers in series with the PFETs of the memory cell with the gate of the PFET header for the row being written being controlled with a pulse write signal from the driver circuit. In some examples of the disclosure, the header transistor circuit may include an NFET pull-down inserted between a virtual-vdd and ground to discharge the virtual-vdd node reducing the contention during a write operation and a clamping NFET in parallel with the PFET header to clamp the virtual-vdd node to slightly below the threshold voltage of the pull-up PFET in the memory cell to ensure the pull-up PFET is barely off and prevent the virtual-vdd node from discharging all the way to ground.