# US 2021/0280258 A1 · Methods of enhancing speed of reading data from memory device

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 2021/0280258 A1
- Document ID: US20210280258A1
- Status: Published application
- Kind: A1
- Application number: 17/330,290
- Filed: 2021-05-25
- Published: 2021-09-09
- Earliest claimed: 2019-11-28
- Assignees: Yangtze Memory Technologies Co., Ltd.
- Applicants: Yangtze Memory Technologies Co., Ltd.
- Inventors: Ke Liang; Li Xiang
- Web page: https://patentgrep.com/patent/US20210280258A1

## CPC

- G11C 16/26: Sensing or reading circuits; Data output circuits
- G11C 11/5642: {Sensing or reading circuits; Data output circuits}
- G11C 16/0483: {comprising cells having several storage transistors connected in series}
- G11C 16/08: Address circuits; Decoders; Word-line control circuits
- G11C 16/32: Timing circuits
- G11C 16/3427: {Circuits or methods to prevent or reduce disturbance of the state of a memory cell when neighbouring cells are read or written}
- G11C: STATIC STORES (semiconductor memory devices H10B)

## Abstract

A memory device includes an array of memory cells, a plurality of word lines coupled to the array of memory cells, a controller configured to control a read operation on the array of memory cells, and a row decoder coupled to the word lines and the controller and configured to, in the read operation, induce a coupling effect between a select word line and an adjacent unselect word line of the plurality of word lines, and discharge the select word line to a start read level due to at least the coupling effect.

## Claims

### Claim 1

A memory device, comprising:
an array of memory cells;
a plurality of word lines coupled to the array of memory cells;
a controller configured to control a read operation on the array of memory cells; and
a row decoder coupled to the word lines and the controller and configured to, in the read operation:
induce a coupling effect between a select word line and an unselect word line of the plurality of word lines, the select word line and the unselect word line being adjacent to one another; and
discharge the select word line to a start read level due to at least the coupling effect.

### Claim 2 (depends on 1)

The memory device of claim 1, wherein to induce the coupling effect, the row decoder is configured to:
drive a voltage on the select word line from a ground level to the start read level below the ground level; and
float the unselect word line while driving the voltage on the select word line from the ground level to the start read level.

### Claim 3 (depends on 2)

The memory device of claim 2, wherein a voltage on the unselect word line is discharged from a second pre-charge level to a first pre-charge level below the second pre-charge level during floating.

### Claim 4 (depends on 3)

The memory device of claim 3, wherein the row decoder is further configured to:
maintain the voltage on the select word line at the start read level; and
maintain the voltage on the unselect word line at the first pre-charge level while maintaining the voltage on the select word line at the start read level.

### Claim 5 (depends on 3)

The memory device of claim 3, wherein the row decoder is further configured to drive the voltage on the unselect word line to the second pre-charge level.

### Claim 6 (depends on 3)

The memory device of claim 3, wherein the row decoder is further configured to drive the voltage on the select word line from the first pre-charge level above the ground level to the ground level.

### Claim 7 (depends on 1)

The memory device of claim 1, wherein to induce the coupling effect, the row decoder is configured to drive a voltage on the unselect word line from a second pre-charge level to a first pre-charge level below the second pre-charge level.

### Claim 8 (depends on 7)

The memory device of claim 7, wherein the row decoder is further configured to float the select word line while driving the voltage on the unselect word line from the second pre-charge level to the first pre-charge level.

### Claim 9 (depends on 8)

The memory device of claim 8, wherein the voltage on the select word line is discharged to the start read level during floating.

### Claim 10 (depends on 7)

The memory device of claim 7, wherein the row decoder is further configured to drive the select word line to the start read level while driving the voltage on the unselect word line from the second pre-charge level to the first pre-charge level.

### Claim 11 (depends on 7)

The memory device of claim 7, wherein the row decoder is further configured to:
maintain the voltage on the select word line at the start read level; and
maintain the voltage on the unselect word line at the first pre-charge level while maintaining the voltage on the select word line at the start read level.

### Claim 12 (depends on 7)

The memory device of claim 7, wherein the row decoder is further configured to drive the voltage on the unselect word line to the second pre-charge level.

### Claim 13 (depends on 7)

The memory device of claim 7, wherein the row decoder is further configured to drive the voltage on the select word line from a ground level above the start read level toward the start read level prior to driving the voltage on the unselect word line from the second pre-charge level to the first pre-charge level.

### Claim 14 (depends on 13)

The memory device of claim 13, wherein the row decoder is further configured to drive the voltage on the select word line from the first pre-charge level above the ground level to the ground level.

### Claim 15

A method for performing a read operation on a memory device, the memory device comprising an array of memory cells, and a plurality of word lines coupled to the array of memory cells, the method comprising:
inducing a coupling effect between a select word line and an unselect word line of the plurality of word lines, the select word line and the unselect word line being adjacent to one another; and
discharging the select word line to a start read level due to at least the coupling effect.

### Claim 16 (depends on 15)

The method of claim 15, wherein inducing the coupling effect comprises:
driving a voltage on the select word line from a ground level to the start read level below the ground level; and
floating the unselect word line while driving the voltage on the select word line from the ground level to the start read level.

### Claim 17 (depends on 16)

The method of claim 16, wherein a voltage on the unselect word line is discharged from a second pre-charge level to a first pre-charge level below the second pre-charge level during floating.

### Claim 18 (depends on 15)

The method of claim 15, wherein inducing the coupling effect comprises driving a voltage on the unselect word line from a second pre-charge level to a first pre-charge level below the second pre-charge level.

### Claim 19 (depends on 18)

The method of claim 18, wherein inducing the coupling effect further comprises floating the select word line while driving the voltage on the unselect word line from the second pre-charge level to the first pre-charge level.

### Claim 20 (depends on 18)

The method of claim 18, wherein inducing the coupling effect further comprises driving the select word line to the start read level while driving the voltage on the unselect word line from the second pre-charge level to the first pre-charge level.