Zero power high speed programmable circuit device architecture

• US 5,440,508 A
• Filed: 02/09/1994
• Issued: 08/08/1995
• Est. Priority Date: 02/09/1994
• Status: Expired due to Term

• Current Assignee: Atmel Corporation (Microchip Technology Incorporated)
• Original Assignee: Atmel Corporation (Microchip Technology Incorporated)
• Inventors: Payne, James E., Pathak, Saroj
• Primary Examiner(s): Popek, Joseph A.
• Application Number:
  US08/194,930
• Time in Patent Office: 545 Days
• Field of Search: 365/154, 365/156, 365/185, 365/190, 365/228
• US Class Current: 365/154
• CPC Class Codes: G11C 14/00 Digital stores characterised by arrangements of cells having volatile and non-volatile storage properties for back-up when the power is down
• CPC Class Codes: G11C 14/0063 and the nonvolatile element is an EEPROM element, e.g. a floating gate or MNOS transistor

Abstract

A non-volatile, low, and zero power, high speed self-sensing programmable device and architecture including a non-volatile self-sensing cell. The non-volatile self-sensing cell is connected out of the speed path of the programmable device, permitting rapid, non-volatile programming and reading operations to be conducted. According to one version, two self-sensing cells are provided with a means for selecting one of the cells for programming or read operation. Each non-volatile self-sensing cell includes a latch having cross-coupled, pull-up transistors and non-volatile pull-down cells. The cross-coupled pull-up transistors are field effect transistors having gates which are connected to the opposite sources of the cross-coupled pull-up transistors.

Claims

1. A non-volatile programmable circuit comprising:

(a) latch means for controlling the application of bitline information, said latch means including first, second, third and fourth terminals,

(b) first and second non-volatile cells, each having a first terminal respectively connected to said first and second terminals of said latch means, said first and second non-volatile cells each having a second terminal connected to a reference potential,

(c) first and second means for respectively selectively connecting said first and second terminals of said latch means to first and second bit lines, whereby bitline information can be communicated and secured in said first and second non-volatile cells, and

(d) a voltage terminal means for providing a plurality of selectable voltage levels relative to said reference potential, said plurality of selectable voltage levels having values other than zero, said third and fourth terminals of said latch means having an electrical connection to said voltage terminal means,

said latch means including first and second transistors, said transistors each having first terminals, second terminals and a control gate, said first terminals of said first and second transistors being coupled respectively to said first and second terminals of said latch means, said control gates being cross coupled to said first terminals of said first and second transistors, said second terminals of said first and second transistors being coupled respectively to said third and fourth terminals of said latch means.

2. The non-volatile programmable circuit according to claim 1, wherein said first and second transistors of said latch means are p-channel field effect devices.

3. The non-volatile programmable circuit according to claim 1, wherein said first and second non-volatile cells include n-channel transistors.

4. The non-volatile programmable circuit according to claim 1, wherein said first and second means for respectively selectively connecting include respective first and second gate-driven transistors which are effective for connecting said first and second terminals to corresponding first and second bitlines in response to gate signals applied to said first and second gate-driven transistors.

5. The non-volatile programmable circuit according to claim 1, wherein said first and second non-volatile cells include field effect transistors in turn including control gate terminals, and the control gate terminals are connected for receipt of a common control signal.

6. The non-volatile programmable circuit according to claim 1, wherein said first and second non-volatile cells include respective first and second floating-gate transistors.

7. The non-volatile programmable circuit according to claim 1, wherein said non-volatile programmable circuit is implemented as an array of zero-power logic gates.

8. A non-volatile programmable logic circuit comprising:

(a) first and second latch transistors having respectively a first terminal and a second terminal, said first and second terminals being connected to a voltage source,

(b) first and second non-volatile pull-down cells respectively connected to said first and second latch transistors, said first and second latch transistors respectively including third and fourth terminals to which said first and second non-volatile cells are respectively electrically connected, said first and second latch transistors being field effect transistors and each having a control gate, said control gates of said first and second latch transistors being connected respectively to said fourth and third terminals, and said second non-volatile pull-down cell being connected to ground, and

(c) means for selectively connecting said third terminal to an input bitline, whereby bitline information can be communicated and secured in said first non-volatile pull-down cell.

9. The non-volatile programmable logic circuit according to claim 8, wherein said first and second latch transistors are p-channel devices.

10. The non-volatile programmable logic circuit according to claim 8, wherein said first and second non-volatile pull-down cells each include in series a select transistor and a floating-gate transistor.

11. The non-volatile programmable logic circuit according to claim 8, wherein said means for selectively connecting said third terminal includes a gate driven transistor effective for connecting said third terminal to a bitline in response to a gate signal applied to said gate driven transistor.

12. The non-volatile programmable logic circuit according to claim 8, wherein said second non-volatile pull-down cell is a field effect transistor including a control gate terminal, and the control gate terminal is connected to said third terminal, whereby the power requirements of said logic circuit are reduced.

13. The non-volatile programmable logic circuit according to claim 8, wherein said non-volatile programmable logic circuit is implemented as an array of zero-power logic gates.

14. A non-volatile programmable circuit comprising:

(a) first and second non-volatile cell means for storing logical information, said first and second non-volatile cell means respectively including first and second non-volatile pull-down transistors being respectively connected to first and second latch transistors, said first and second latch transistors respectively including first and second terminals to which said first and second non-volatile pull-down transistors are respectively electrically connected, said first and second latch transistors each having a control gate, and the control gates of said first and second latch transistors being connected respectively to said second and first terminals, said first and second latch transistors having third and fourth terminals, said third and fourth terminals being connected to a voltage source,

(b) bitline transistor means for connecting said first and second non-volatile cell means to a single sensing bitline, said bitline transistor means including a control gate connected to both said first and second non-volatile cell means, and

(c) selection means for interruptably connecting the control gate of the bitline transistor means and said respective first and second non-volatile cell means, said selection means being effective for selecting one of said first and second non-volatile cell means for communication with the control gate of the bitline transistor means.

15. A non-volatile programmable circuit, comprising:

(a) first and second non-volatile self-sensing programmable cell means for storing and communicating information,

(b) a single bitline means for receiving information from said first and second non-volatile self-sensing programmable cell means,

(c) selection means for selecting one of said first and second non-volatile self-sensing programmable cell means, and

(d) switch means for sensing information stored in one of said first and second non-volatile self-sensing programmable cell means, said switch means including first and second terminals and a control gate, said control gate being connected to said selection means and said single bitline means being connected to said first terminal, the selected one of said first and second non-volatile self-sensing programmable cell means being sensed by said single bitline means.

16. The non-volatile programmable circuit of claim 15, further comprising means for programming said first and second non-volatile cell means.

17. The non-volatile programmable circuit of claim 16, wherein said means for programming is connected to said bitline means.

18. The non-volatile programmable circuit of claim 15, further comprising a second bitline means for communicating information to said first and second non-volatile self-sensing programmable cell means.

19. The non-volatile programmable circuit of claim 18, wherein said first and second non-volatile self-sensing programmable cell means are programmed from said second bitline means via a means for programming connected to said second bitline means.

20. The non-volatile programmable circuit of claim 15, wherein said non-volatile programmable circuit is implemented as an array of zero-power logic gates.