Systems and methods for reducing standby power in floating body memory devices

• US 10,354,718 B2
• Filed: 11/13/2018
• Issued: 07/16/2019
• Est. Priority Date: 07/10/2013
• Status: Active Grant

• Current Assignee: Zeno Semiconductor, Inc.
• Original Assignee: Zeno Semiconductor, Inc.
• Inventors: Louie, Benjamin S., Widjaja, Yuniarto
• Primary Examiner(s): Le, Vu A
• Application Number:
  US16/189,806
• Publication Number:
  US 20190080746A1
• Time in Patent Office: 245 Days
• Field of Search: 3652101
• CPC Class Codes: G11C 11/412 using field-effect transistors only
• CPC Class Codes: G11C 11/417 for memory cells of the field-effect type
• CPC Class Codes: G11C 5/147 Voltage reference generators, voltage or current regulators; Internally lowered supply levels; Compensation for voltage drops G11C5/141 takes precedence
• CPC Class Codes: G11C 5/148 Details of power up or power down circuits, standby circuits or recovery circuits

Abstract

Methods, devices, arrays and systems for reducing standby power for a floating body memory array. One method includes counting bits of data before data enters the array, wherein the counting includes counting at least one of: a total number of bits at state 1 and a total number of all bits; a total number of bits at state 0 and the total number of all bits; or the total number of bits at state 1 and the total number of bits at state 0. This method further includes detecting whether the total number of bits at state 1 is greater than the total number of bits at state 0; setting an inversion bit when the total number of bits at state 1 is greater than the total number of bits at state 0; and inverting contents of all the bits of data before writing the bits of data to the memory array when the inversion bit has been set.

Claims

1. A semiconductor memory array configured for reducing standby power, said array comprising:

a plurality of floating body memory cells configured to store charge representative of data; and

at least two floating body cells serially connected to form a reference cell;

wherein current conducted through said at least one of said plurality of floating body memory cells is reduced to a fraction of said current when passing through said reference cell.

2. The array of claim 1, wherein said at least two floating body cells of said reference cell are set to state 1.

3. The array of claim 1, wherein said reference cell is used for at least one of:

a current reference, a voltage reference or a monitor of transient response to bit line discharge.

7. The array of claim 1, further comprising source isolation devices configured to set said reference cell to state 1.

8. The array of claim 7, wherein said source isolation devices are off during normal operation.

9. The array of claim 7, wherein said source isolation devices are configured to be activated to set said reference cell to state 1.

4. A semiconductor memory array configured for reducing standby power, said array comprising:

a plurality of floating body memory cells configured to store charge representative of data; and

at least two more of said floating body memory cells interconnected by a segmented source line to form a reference cell.

5. The array of claim 4, comprising:

a plurality of said reference cells connected in a dedicated column or row of said array and to different rows or columns of said floating body memory cells configured to store charge representative of data; and

a dedicated reference bit line connected to said plurality of reference cells.

6. The array of claim 4, comprising:

a plurality of said reference cells connected to different rows or columns of said floating body memory cells configured to store charge representative of data; and

source isolation devices connected between said reference cells.

10. The array of claim 4, further comprising source isolation devices configured to set said reference cell to state 1.

11. The array of claim 10, wherein said source isolation devices are off during normal operation.

12. The array of claim 10, wherein said source isolation devices are configured to be activated to set said reference cell to state 1.