Sandisk Technologies Inc.

Yosuke Kato

Man Lung Mui

Seungpil Lee

Yingda Dong

Ken Oowada

Teruhiko Kamei

Fumitoshi Ito

Norihiro Kamae

Shingo Zaitsu

Chang Hua Siau

Hao Nguyen

Gopinath Balakrishnan

Naoki Ookuma

Wanfang Tsai

Methods for improving read time performance and energy consumption when reading multiple pages within a memory block by dynamically skipping or accelerating unselected word line discharge cycles are described. In some cases, a controller or one or more control circuits in communication with word lines and bit lines associated with a memory block may detect that a read command or instruction for reading a second page within the memory block has arrived prior to the word line discharge phase associated with reading a first page within the memory block, and in response, the controller may skip the discharge cycle for unselected word lines within the memory block prior to reading the second page and initiate the next page read for the second page after a partial discharge period of time.

Word line discharge skip for faster read time

Sensing techniques and associated circuitry are provided for use with a memory device. The techniques are suited for sensing operations involving even-numbered or odd-numbered bit lines. In one approach, a mapping between caches and sense amplifiers in a sensing circuit is modified by using dual data buses. One bus is used for same-tier transfers and the other is used for cross-tier transfers. Each tier comprises a set of sense amplifiers and a corresponding set of caches. This approach does not require a modification of the input/output path which is connected to the sensing circuitry.

Data mapping for non-volatile storage

Sensing techniques and associated circuitry are provided for use with a memory device. The techniques are suited for sensing operations involving even-numbered or odd-numbered bit lines. In one approach, the sensing circuitry includes left and right hand portions which have separate cache access lines, but are connected to a common output bus. A full data word can be output at a time by using a half word from the left hand portion and a half word from the right hand portion. Or, the sensing circuitry can be configured so that a full data word is output at a time from the left or right hand portion. One implementation provides an N-bit bus and N input paths for each of the left and right hand portions. Another implementation provides an N-bit bus and N/2 input paths for each of the left and right hand portions.

Fast read for non-volatile storage

A compact and versatile high speed sense amplifier suitable for use in non-volatile memory circuits is presented. The sense amp circuit uses one power supply level for the bit line driving path and a second supply level for a data latch of the sense amp. The latch's supply level is of a high level that used for driving the bit lines and can be provided by a charge pump. The sense amp need use only NMOS devices for its analog path. For balancing performance and current consumption, the sense amp also includes an additional latch to support a 'hybrid lockout' sensing mode, where in a verify operation a read-lockout is used between different data states, but not between the low and high quick pass write (QPW) verifies.

Compact high speed sense amplifier for non-volatile memory and hybrid lockout

Upon selecting non-volatile storage elements to be sensed, the system obtains information about the position of these non-volatile storage elements, determines sensing parameters based at least in part on this information, pre-charges a charge storage device and, while maintaining the voltage level of the bit lines of these memory cells at a constant value, applies a reference signal to these non-volatile storage elements for a certain duration of time, afterwards determining whether, for the certain duration of time, the current conducted by these non-volatile storage elements exceeds a predetermined value.

Bit line current trip point modulation for reading nonvolatile storage elements

A nonvolatile memory array is organized into a plurality of interleaving even and odd blocks. When a block is selected for operation, a set of word line voltages are delivered to the block of word lines by space-efficient decoding circuits and scheme. The plurality of blocks is organized into an array of pairs of adjacent odd and even blocks. A first voltage bus allows all even blocks access to the set of word line voltages. A second voltage bus allows all odd blocks access to the set of word line voltages. A decoder for selection is provided for each pair of adjacent even and odd blocks. Selecting a block is effected by selecting the pair of adjacent even and odd blocks containing the selected block, and supplying the set of word line voltages only to the selected block, which is one of the even or odd block in the selected pair.

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Yokohama, Japan

Yosuke Kato