Novel nand array architecture for multiple simutaneous program and read
AssigneeAplus Flash Technology, Inc.
InventorPeter Wung Lee
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AssigneeAplus Flash Technology, Inc.
InventorPeter Wung Lee
Estimating the term…
This invention discloses a HiNAND array scheme with multiple-level of bit lines (BLs) including metal3 global bit lines (GBLs), divided metal2 Segment bit lines (SBLs), and divided metal1 block bit lines (BBLs) laid out in parallel to each other respectively for a plurality of NAND Strings. All other source lines or power lines connected to bottoms of corresponding String capacitances of GBLs, SBLs, and BBLs are associated with metal0 line laid out perpendicular to those BLs. Under the HiNAND array scheme, conventional one-WL Read and Program-Verify operations are replaced by multiple-WL and All-BL Read and Program-Verify operations executed with charge capacitance of SBLs being reduced to 1/10- 1/20 of capacitance of GBLs to achieve DRAM-like faster operation, less operation stress, and lower power consumption. A preferred set of program biased voltages on the selected WL and remaining non-selected WLs associated with a Multiplier and a DRAM-like charge-sharing Latch Sensing Amplifier is proposed.
A method of performing multiple-WL & All-BL Read, Erase-Verify, and Program-Verify operations in a HiNAND memory array with BL-hierarchical structure, the method comprising,
The method of claim 14 further comprising pre-discharging N GBLs by setting the first gate signal to Vdd to turn on the N first GBL-select transistors to connect with the first power/Vss line in ground level 0V, pre-discharging N SBLs comprises setting the third gate signal to Vdd to turn on the N first SBL-select transistors to connect with the second power/Vss line in ground level 0V, and pre-discharging N BBLs comprises setting the fifth gate signal to Vdd to turn on the N BBL-select transistors to connect with the third power/Vss line in ground level 0V.
The method of claim 14 wherein pre-charging the N BBLs and the N SBLs comprises supplying Vdd or up to 7V to the corresponding second power/Vss line, setting the third gate signal and the fourth gate signal to Vdd+Vt up to 7V+Vt depending on the BVDS of transistors connected to SBLs, BBLs, and GBLs to turn on the N first SBL-select transistors to connect the N SBLs to the N BBLs, and setting the fifth gate signal from Vdd to 0V, both the N SBLs and the N BBLs being isolated from the N GBLs by setting the second gate signal to 0V, the pre-charge voltage being stored at parasitic capacitances associated with the BBLs at the metal1 level connected with the corresponding SBLs at metal2 level within one selected Segment.
The method of claim 14 wherein further comprising resetting the N GBLs after performing a Read operation on one selected page in a selected Block by grounding the first power/Vss line and switching the first gate signal to Vdd or higher for turning on all the N first GBL-select transistors respectively connected between the N GBLs and the first power/Vss line.
A method of performing simultaneous multiple-WL and All-BL Program operation in a NAND memory array with BL-hierarchical structure, the method comprising:
Dependencies are inferred from the claim text.