发明名称 |
Method for multilevel DRAM sensing |
摘要 |
A method for performing a sense and restore operation in a multilevel DRAM is described. The method describes the selective enabling of the sense amplifiers to operate at predetermined sensing thresholds. The multilevel DRAM stores two bits per cell using a four-voltage-level-per-cell system. Folded bitlines are divided into sub-bitlines each having dedicated sense amplifiers. The sense amplifiers are selectively enabled to operate at predetermined sensing thresholds to thereby greatly simplify the sense and restore operations. The circuit has standard CMOS bitline sense amplifier transistors connected thereto with pull down transistors that may be selectively enabled by switch signals. The length and width of these pull down transistors are varied to thereby effect the switching threshold of the sense amplifier.
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申请公布号 |
US6151260(A) |
申请公布日期 |
2000.11.21 |
申请号 |
US19980046636 |
申请日期 |
1998.03.24 |
申请人 |
MOSAID TECHNOLOGIES INCORPORATED |
发明人 |
BIRK, GERSHOM |
分类号 |
G11C11/4091;G11C11/56;(IPC1-7):G11C7/02 |
主分类号 |
G11C11/4091 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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