Abstract: The present invention discloses a ROM memory cell that has significantly less total area than previously known ROM memory cells. Instead of using only one layer in the manufacturing process to program the memory cells, the present invention uses at least two layers to program the memory cells. This flexibility allows the memory cell to be reduced in area, which in turn produces a ROM that is more area efficient and consequently lower in cost. As the bitline length and capacitance are reduced, the speed and power consumption are also improved.

Abstract: In accordance with an aspect of an input/output device for providing fast translation between differential signals from a core of an integrated circuit and higher voltage signals that are external to the core, an I/O buffer includes low voltage devices for receiving core input signals, a cascode stage for setting a bias between the input devices and an output stage, and an output stage including a current mirror for providing a translated external output. Another aspect of the invention further includes a feedback path to cut off the current mirror to prevent static current and a keeper device to maintain an output level after cut off of the current mirror.

Abstract: An invention is provided for a feed forward circuit that reduces delay through an inverting circuit. The feed forward circuit includes an inverter having an input and an output, and an inverting circuit having an input and an output. The input of the inverting circuit is coupled to the output of the inverter. A feed forward transistor having a gate coupled to the input of the inverter and a terminal coupled to the output of the inverting circuit also is included. In operation the feed forward transistor decreases the amount of time required for the output of the inverting circuit to change state. In sum, the invention reduces the delay when the inverting circuit transitions to a high state, without affecting the timing of the transition to a low state.

Abstract: A Static Random Access Memory (SRAM) dual port memory with an improved core cell design having internally matched capacitances and decreased bit line capacitance is disclosed. The core cell is fabricated on a substrate divided into three approximately equal columns of different substrate materials. In a preferred embodiment, the memory cell is fabricated on a central p-type column that in turn is sandwiched between two n-type columns. The three-column substrate architecture permits reduced bit line height, with an accompanying reduction in bit line capacitance, which increases the speed at which the core cell can operate. The architecture also permits separating the core cell's bitline and complement bitline, reducing capacitive coupling between these lines and increasing the core cell's operating speed. The architecture further permits better matching of internal node capacitances.

Abstract: In an environment wherein a microprocessor can operate at several different voltage levels depending upon the instantaneous throughput of the microprocessor, a memory and memory adjustment circuit that permits operating the memory at a plurality of voltages in response to the microprocessor is disclosed. The memory and memory adjustment circuit sense the instantaneous operating voltage of the microprocessor and adjust the operating voltage of the memory in response thereto. The memory adjustment circuit more particularly increases or decreases the memory's bitline sense interval in response respectively to a decrease or increase in the memory's operating voltage.