Dynamic Random Access Memory Sense Amplifier With Common Set/ Restore Node
Original Publication Date: 1985-Aug-01
Included in the Prior Art Database: 2005-Feb-19
This circuit reduces the area required for a cross-coupled FET sense amplifier by coupling sense node restore devices in parallel with the cross-coupled devices such that charging of the sense nodes is provided through the pre-charged set node as it is restored to VH. In a conventional 6-device sense amplifier design, devices 1 and 2 are cross-coupled to form an amplifying latch. Devices 5 and 6 are connected to +VH and are gated by a restore switch line. The new approach consists of connecting devices 5 and 6 to the set node instead of +VH, as shown in the figure. The timing shown applies to both the new and the old sense amplifier operation. In the new approach, the circuitry which restores the set node to +VH must also be able to supply the current necessary to restore all of the bit lines.