Configurable electrical circuit having configurable logic elements and configurable interconnects

• US 4,870,302 A
• Filed: 02/19/1988
• Issued: 09/26/1989
• Est. Priority Date: 03/12/1984
• Status: Expired

• Current Assignee: Xilinx, Inc. (Advanced Micro Devices, Inc.)
• Original Assignee: Xilinx, Inc. (Advanced Micro Devices, Inc.)
• Inventors: Freeman, Ross H.
• Primary Examiner(s): Miller, Stanley D.
• Assistant Examiner(s): HUDSPETH, DAVID R
• Application Number:
  US07/158,011
• Time in Patent Office: 585 Days
• Field of Search: 307/465, 307/466, 307/467, 307/468, 307/469, 307/471, 364/716, 364/784, 340/825.83-825.91
• US Class Current: 326/41
• CPC Class Codes: H03K 19/1736 in which the wiring can be modified
• CPC Class Codes: H03K 19/17704 the logic functions being realised by the interconnection of rows and columns
• CPC Class Codes: H03K 19/17736 Structural details of routing resources
• CPC Class Codes: H03K 19/1776 for memories
• CPC Class Codes: H03K 19/17772 for powering on or off

Abstract

A configurable logic array comprises a plurality of configurable logic elements variably interconnected in response to control signals to perform a selected logic function. Each configurable logic element in the array is in itself capable of performing any one of a plurality of logic functions depending upon the control information placed in the configurable logic element. Each configurable logic element can have its function varied even after it is installed in a system by changing the control information placed in that element. Structure is provided for storing control information and providing access to the stored control information to allow each configurable logic element to be properly configured prior to the initiation of operation of the system of which the array is a part. Novel interconnection structures are provided to facilitate the configuring of each logic element.

Claims

1. An interconnect structure for programmably interconnecting lines within an integrated circuit comprising:

at least three sets of interconnect line including a first set, a second set, and a third set;

programmable means, not including said sets of interconnect lines, for connecting at least one of said lines in said first set to at least one of said lines in said second set, for connecting at least one of said lines in said first set to at least one of said lines in said third set, and for connecting at least one of said lines in said second set to at least one of said lines in said third set.

2. An array of interconnect structures, each said interconnect structure as in claim 1, and each interconnect structure in said array having its own selected number of interconnect lines and its own programmable means for connecting interconnect lines in its own first, second and third sets.

3. An interconnect structure as in claim 1 in which

said first set comprises two lines;

and

said programmable means comprises

means for connecting each of said two lines in said first set to at least one line in said second set and

means for connecting each of said two lines in said first set to said at least one line in said third set.

4. An array of interconnect structures, each said interconnect structure as in claim 3, and each interconnect structure in said array having its own selected number of interconnect lines and its own programmable means for connecting interconnect lines in its own first, second and third sets.

5. An interconnect structure as in claim 3 in which

said second set comprises two lines, and

said third set comprises two lines;

and

said programmable means comprises

means for connecting each of said two lines in said first set to each of said two lines in said second set,

means for connecting each of said two lines in said first set to each of said two lines in said third set, and

means for connecting each of said two lines in said second set to each of said two lines in said third set.

6. An array of interconnect structures, each said interconnect structure as in claim 5, and each interconnect structure in said array having its own selected number of interconnect lines and its own programmable means for connecting interconnect lines in its own first, second and third sets.

7. An interconnect structure as in claim 5 in which said at least three sets of interconnect lines includes a fourth set, and said interconnect structure further comprises:

programmable means for connecting at least one of said lines in said fourth set to at least one of said lines in said first, second and third sets.

8. An array of interconnect structures, each said interconnect structure as in claim 7, and each interconnect structure in said array having its own selected number of interconnect lines and its own programmable means for connecting interconnect lines in its own first, second, third and fourth sets.

9. An interconnect structure as in claim 7 in which said programmable means for connecting at least one of said lines in said first, second, third, and fourth sets comprises programmable means for connecting said two lines in said first set to each of said two lines in said second set, for connecting said two lines in said first set to each of said two lines in said third set, for connecting said two lines in said first set to each of two lines in said fourth set, for connecting said two lines in said second set to each of said two lines in said third set, for connecting said two lines in said second set to each of said two lines in said fourth set, and for connecting said two lines in said third set to each of said two lines in said fourth set.

10. An array of interconnect structures, each said interconnect structure as in claim 9, and each interconnect structure in said array having its own selected number of interconnect lines and its own programmable means for connecting.

11. A configurable system comprising:

one master configurable logic array;

a plurality of slave configurable logic arrays;

at least one memory;

said master configurable logic array having

means for retrieving data from said at least one memory,

means for first using said data for configuring itself, and

means for passing some of said data to said

plurality of slave configurable logic arrays.

12. A configurable system as in claim 11 in which said means for retrieving data from said at least one memory includes

means for addressing said memory cells in said at least one memory, and

means for transferring selected data from said at least one memory to said master configurable logic array.

13. A configurable system as in claim 11 in which said plurality of slave configurable logic arrays include

means for being configured and

means for receiving and passing said data from said master configurable logic array to said plurality of slave configurable logic arrays whereby each of said slave configurable logic arrays is programmed according to said data in said at least one memory.

14. A configurable system as in claim 11 in which said means for passing some of said data to said plurality of slave configurable logic arrays comprises

means for passing said data through said plurality of slave configurable logic arrays sequentially by means of a shift register controlled by clock signals provided by said master configurable logic array.

20. A configurable system as in claim 11 wherein said memory is nonvolatile.

15. A configurable system comprising:

a master configurable logic array;

a plurality of slave configurable logic arrays; and

a controller including

means for addressing said configurable logic arrays and

means for sending data to said configurable logic arrays;

wherein said master configurable logic array includes

means for being configured by said data from said controller and

means for configuring said slave configurable logic arrays.

16. A configurable system as in claim 15 in which said slave configurable logic arrays include means for being configured and means for receiving and passing said data from said master configurable logic array.

17. A configurable system as in claim 15 in which said means for addressing further includes means for controlling sending said data from said means for sending data.

18. A configurable system as in claim 15 in which said means for configuring said slave configurable logic arrays comprises means for receiving data from said controller, means for passing some of said data to said slave configurable logic arrays and means for controlling the passing of said data to said slave configurable logic arrays.

19. A configurable system as in claim 15 in which said means for being configured of said master configurable logic array comprises means for receiving configuration control bits from said controller, and said means for configuring said slave configurable logic arrays comprises means for passing said data through said plurality of slave configurable logic arrays sequentially by means of a shift register as controlled by clock signals provided by said master configurable logic array.

21. A programmable circuit comprising:

a plurality of configurable logic elements, each configurable logic element having a plurality of input leads and at least one output lead and having a programming means to cause said configurable logic element to perform a selected logic function;

a plurality of input/output ports;

a group of interconnect lines;

means for programmably connecting each of said input leads of each of said configurable logic elements to at least one of said interconnect lines;

means for programmably connecting said at least one output lead of each of said configurable logic elements to at least one of said interconnect lines;

means for programmably connecting each of said input/output ports to at least one of said interconnect lines; and

means for programmably connecting each one of said interconnect lines to at least one other of said interconnect lines;

whereby each of said input leads and each of said at least one output lead of each of said configurable logic elements can be connected directly or indirectly to each of said input/output ports and to each other, and whereby each of said configurable logic elements can be programmed to perform a selected one of a plurality of logic functions, and said configurable logic elements can be connected to each other and to said input/output ports in a selectable manner.

22. A programmable circuit as in claim 21 wherein said programming means of each of said configurable logic elements comprises logic element pass transistors.

23. A programmable circuit as in claim 22 wherein said programming means includes a plurality of memory cells and wherein each of said logic element pass transistors is controlled by a corresponding one of said plurality of memory cells.

24. A programmable circuit as in claim 23 in which said plurality of memory cells forms at least part of a shift register, control signals being loaded into said memory cells by being transferred through said shift register until each of said signals is properly located in said corresponding one of said memory cells.

25. A programmable circuit as in claim 23 in which said memory cells can be re-programmed.

26. A programmable circuit as in claim 21 in which each of said interconnect lines is capable of being connected directly or indirectly to one or more of the other of said interconnect lines, to one or more of said input/output ports, to one or more of said input leads and to one or more of said output leads, thereby allowing a user to connect said leads and lines together as desired.

27. A programmable interconnect circuit as in claim 21 wherein said means for programmably connecting each of said input leads of each of said configurable logic elements to at least one of said interconnect lines, said means for programmably connecting said at least one output lead of each of said configurable logic elements to at least one of said interconnect lines, said means for programmably connecting each of said input/output ports to at least one of said interconnect lines, and said means for programmably connecting each of said interconnect lines to at least one other of said interconnect lines comprise pass transistors.

28. A programmable circuit as in claim 27

wherein said means for programmably connecting further comprises memory cells, said memory cells forming at least part of a shift register,

wherein each of said pass transistors is controlled by one of said memory cells, and

wherein said means for programmably connecting further comprises means for transferring said series of signals through said shift register until each of said signals is properly located in an associated one of said memory cells uniquely coupled to one of said pass transistors.

29. A programmable circuit as in claim 28 in which said means for programmably connecting includes means for changing the contents of said memory cells, thereby to reconfigure said programmable circuit.