OPTION FUSE CIRCUIT USING STANDARD CMOS MANUFACTURING PROCESS

• US 20040125638A1
• Filed: 12/25/2002
• Published: 07/01/2004
• Est. Priority Date: 12/25/2002
• Status: Active Grant

• Current Assignee: Ememory Technology Inc.
• Original Assignee: Ememory Technology Inc.
• Inventors: Huang, Jie-Hau, Lin, Yen-Tai
• Granted Patent: US 6,775,189 B2
• Time in Patent Office: Days
• US Class Current: 365/96
• CPC Class Codes: G11C 17/16 using electrically-fusible links

Abstract

An option fuse circuit using standard CMOS manufacturing processes includes a latch for latching signals, which includes a first node and a second node. The option fuse circuit also includes a comparator, which includes two input nodes and an output node. The comparator receives signals input at the two input nodes from the first and the second nodes, and compares the two signals in order to output a comparison signal. The option fuse circuit further includes two logic cells for storing non-volatile data. The logic cells include a word line node and a bit line node. The word line nodes are electrically connected to the output node of the comparator, while the bit line nodes are electrically connected to the first and the second nodes, respectively.

Claims

1. An option fuse circuit manufactured with standard CMOS manufacturing processes, comprising:

a latch comprising a first node and a second node, and being used for latching signals at the first and the second nodes;

a comparator comprising two input nodes and an output node, wherein the two input nodes are electrically connected to the first and the second nodes respectively, the comparator being used for inputting the signals at the first and the second nodes respectively, and outputting a comparison signal by comparing the two signals;

a first logic cell for storing a non-volatile data, comprising a first word line node and a first bit line node, wherein the first word line node is electrically connected to the output node of the comparator in order to input the comparison signal, the first bit line node being electrically connected to the first node; and

a second logic cell for storing a non-volatile data, comprising a second word line node and a second bit line node, wherein the second word line node is electrically connected to the output node of the comparator in order to input the comparison signal, the second bit line node being electrically connected to the second node;

wherein the data stored in the first logic cell and the data stored in the second logic cell are complementary to each other.

2. The option fuse circuit of claim 1 wherein when the option fuse circuit is in a read mode and power is turned on, a power supply voltage increases with time until reaching a predetermined value, and voltages at the first and the second nodes increase according to the power supply voltage.

3. The option fuse circuit of claim 2 wherein when the voltages at the first and the second bit line nodes are equivalent to each other during the increment, both the first and the second logic cells turn on according to the comparison signal outputted from the comparator, the first node sensing the data stored in the first logic cell, the second node sensing the data stored in the second logic cell.

4. The option fuse circuit of claim 2 wherein when the voltages at the first and the second nodes differ from each other during the increment, the first and the second logic cells turn off according to the comparison signal outputted from the comparator, the latch latching the signals at the first and the second nodes.

5. The option fuse circuit of claim 1 wherein the latch is formed by connecting two inverters reversely.

6. The option fuse circuit of claim 5 wherein each inverter is formed with a PMOS transistor and an NMOS transistor, gates of the two transistors being electrically connected to each other to form an input node of the inverter, and drains of the two transistors being electrically connected to each other to form an output node of the inverter.

7. The option fuse circuit of claim 1 wherein the comparator further comprises a plurality of logic gates for comparing the signals at the first and the second nodes, so as to output the comparison signal at the output node.

8. The option fuse circuit of claim 1 wherein the comparator further comprises a mode-selecting input node for determining whether the option fuse circuit is in a program mode or in a read mode.

9. The option fuse circuit of claim 1 wherein the comparator further comprises a data-programming input node for writing data to be written into the first and the second logic cells when the option fuse circuit is in a program mode.

10. The option fuse circuit of claim 1 wherein the first and the second logic cells are one-time programmable logic cells.

11. The option fuse circuit of claim 10 wherein the one-time programmable logic cell comprises a first transistor and a second transistor, a source of the first transistor being electrically connected to a power supply voltage or to ground, a gate of the first transistor being the word line node of the logic cell, a drain of the first transistor being electrically connected to a source of the second transistor, a gate of the second transistor floating, and a drain of the second transistor being the bit line node of the logic cell.

12. The option fuse circuit of claim 11 wherein the first and the second transistors are PMOS transistors, the source of the first transistor being electrically connected to a high-level voltage.

13. The option fuse circuit of claim 11 wherein the first and the second transistors are NMOS transistors, the source of the first transistor being electrically connected to ground (0V).

14. The option fuse circuit of claim 1 further comprising an initialization module electrically connected to the first and the second logic cells, and used for writing data to be written into the first and the second logic cells during a program mode.

15. The option fuse circuit of claim 14 wherein the initialization module comprises a first initializing transistor and a second initializing transistor, the first and the second initializing transistors being NMOS transistors, drains of the first and the second initializing transistors being electrically connected to the first and the second bit line nodes respectively, sources of the first and the second initializing transistors being electrically connected to ground, the comparator further comprising two initializing output nodes with signals of opposite phases, the two initializing output nodes being electrically connected to gates of the first and the second initializing transistors respectively, and used for controlling turn-on of the first and the second initializing transistors so as to write the data into the first and the second logic cells.

16. The option fuse circuit of claim 14 wherein the initialization module comprises a first initializing transistor and a second initializing transistor, the first and the second initializing transistors being PMOS transistors, drains of the first and the second initializing transistors being electrically connected to the first and the second bit line nodes respectively, sources of the first and the second initializing transistors being electrically connected to a high-level voltage, the comparator further comprising two initializing output nodes with signals of opposite phases, the two initializing output nodes being electrically connected to gates of the first and the second initializing transistors respectively, and used for controlling turn-on of the first and the second initializing transistors so as to write the data into the first and the second logic cells.

17. The option fuse circuit of claim 1 wherein the comparator further comprises a signal output node for outputting the signal latched by the latch.