IP Library Granted Patent US 10,438,952
Granted Patent B2
US 10,438,952 · App. 15/658,346 · Granted Oct 8, 2019

Method of writing into and refreshing a thyristor volatile random access memory

Inventors: Harry Luan (Saratoga, CA); Bruce L. Bateman (Fremont, CA); Valery Axelrad (Woodside, CA); Charlie Cheng (Los Altos, CA)
Assignee: TC Lab, Inc.
H01L27/1027G11C11/39H01L21/28035H01L21/321H01L21/324H01L21/76224H01L28/00H01L29/0649H01L29/102H01L29/1016H01L29/16H01L29/45H01L29/456H01L29/66356H01L29/66363H01L29/749H01L29/0834H01L29/4236
View Patent ↗
Loading inventors, assignments & file history…
Monitor This Case
Get email alerts when status or documents change.
Order Certified Copies
Most orders are placed with the USPTO same day — all within 24 business hours.
Order via The Patent Place →
Pre-filled with this patent's details
Quick Facts
Patent No.
US 10,438,952
App. No.
15/658,346
Granted
Oct 8, 2019
Kind
B2
Abstract

A method of writing data into a volatile thyristor memory cell array and maintaining the data with refresh is disclosed.

Claims (7)

1. A method of dynamically operating an array of vertical thyristor memory cells, the array intersected by a plurality of first and second lines, the first lines orthogonal to the second lines, each vertical thyristor memory cell having an anode coupled to one of the first lines and having a cathode coupled to the one of the second lines, the method comprising:

writing data into the vertical thyristor memory cells of the array, the written data stored as the vertical thyristor memory cells turned off or on, including setting a first voltage on a selected one of the first lines and a second voltage on a selected one of the second lines to apply a voltage differential in a range of 2.4-3 volts across the selected one first line and the selected one second line, and across a selected vertical thyristor memory cell at an intersection of the selected one first line and the selected one second line to turn on the selected vertical thyristor memory cell and setting a third voltage on non-selected first lines and a fourth voltage on non-selected second lines at half the voltage differential applied to the selected vertical thyristor memory cell to provide a voltage differential in a range about 0 volts of across the non-selected first line and the non-selected second lines, and across non-selected vertical thyristor memory cells at intersections of the non-selected first lines and the non-selected second lines to leave data stored on the non-selected vertical thyristor memory cells unchanged;

allowing the turned on vertical thyristor memory cells to discharge; and

periodically refreshing all the turned on vertical thyristor memory cells in the array before loss of data so that the data stored in the memory cells of the array is maintained.

2. The method of claim 1 wherein the vertical thyristor memory cell refreshing step comprises refreshing the turned on vertical thyristor memory cells of the array from 1-10 times a second.

3. The method of claim 1 wherein the vertical thyristor memory cell array refreshing step comprises driving a current from the one of the first lines connected to the anode to the one of the second lines connected to the cathode of a turned on vertical thyristor memory cell in the array.

4. The method of claim 3 wherein a magnitude of the driven current is larger than a magnitude of a current in the turned on vertical thyristor memory cell immediately prior to the vertical thyristor memory cell refreshing step.

Assignments (2)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded May 12, 2018
From: KILOPASS TECHNOLOGY, INC.
To: TC LAB, INC.
Reel/Frame 045790/0860 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded May 10, 2018
From: LUAN, HARRY; BATEMAN, BRUCE L.; AXELRAD, VALERY; CHENG, CHARLIE
To: KILOPASS TECHNOLOGY, INC.
Reel/Frame 045774/0808 →
Continuity (5)
Continuation 14841140 · Aug 31, 2015
Continuation In Part 14590834 · Jan 6, 2015
Provisional Application 62186336 · Jun 29, 2015
Provisional Application 62055582 · Sep 25, 2014
Related Publication 20170323891A1 · Nov 9, 2017