Small-Sized Leakage-Controlled Gated Sense Amplifier for 0.5-V Multi-Gigabit DRAM Arrays
A small-sized leakage-controlled gated sense amplifier (SA) and relevant circuits are proposed for 0.5-V multi-gigabit DRAM arrays. The proposed SA consists of a high-<i>V</i><sub>T</sub> PMOS amplifier and a low-<i>V</i><sub>T</sub> NMOS amplifier which is composed of high-<i>V</i><sub>T</sub> NMOSs and a low-<i>V</i><sub>T</sub> cross-coupled NMOS, and achieves 46% area reduction compared to a conventional SA with a low-<i>V</i><sub>T</sub> CMOS preamplifier. Separation of the proposed SA and a data-line pair achieves a sensing time of 6ns and a writing time of 0.6ns. Momentarily overdriving the PMOS amplifier achieves a restoring time of 13ns. The gate level control of the high-<i>V</i><sub>T</sub> NMOSs and the gate level compensation circuit for PVT variations reduce the leakage current of the proposed SA to 2% of that without the control, and its effectiveness was confirmed using a 50-nm test chip.
- IEICE transactions on electronics
IEICE transactions on electronics 95(4), 594-599, 2012-04-01