Method of improving fuse state detection and yield in semiconductor applications

A method of detecting the state of fuses as blown or un-blown, said method comprising:

• passing a first current from a first current source through a plurality of first fuses that are electrically connected in series and also to a first input of a voltage difference detection device;
• passing a second current from a second current source through a plurality of second fuses that are electrically connected in series and also to a second input of said voltage difference detection device,
• wherein said first fuses and said second fuses all comprise identical fuses and wherein said second fuses are not blown;
• and
• comparing, by said voltage difference detection device, a first voltage at said first input to a second voltage at said second input to determine whether said first fuses are blown.

A method of detecting the state of fuses as blown or un-blown, said method comprising:

• passing a first current from a first current source through at least one first fuse and also to a first input of a voltage difference detection device;
• passing a second current from a second current source different from said first current source through at least one second fuse and also to a second input of said voltage difference detection device,
• wherein said at least one first fuse and said at least one second fuse all comprise identical fuses,
• wherein said at least one second fuse is not blown,
• wherein said first current source comprises a first p-type field effect transistor having a first gate width and said second current source comprises a second p-type field effect transistor having a second width, and
• wherein said first gate width is less than said second gate width so that said first current is less than said second current;
• and
• comparing a first voltage at said first input to a second voltage at said second input to determine whether said at least one first fuse is blown,
• wherein said at least one first fuse comprises a plurality of first fuses and said at least one second fuse comprises a plurality of same number second fuses and wherein by passing of said first current through said first fuses as opposed to one first fuse and by passing of said second current through said second fuses as opposed to one second fuse, said method proportionately increases a voltage difference that will be detectable.

A method of detecting the state of fuses as blown or un-blown, said method comprising:

• passing a first current from a first current source through at least one first fuse and also to a first input of a voltage difference detection device;
• passing a second current from a second current source different from said first current source through at least one second fuse and also to a second input of said voltage difference detection device,
• wherein said at least one first fuse and said at least one second fuse all comprise identical fuses,
• wherein said at least one second fuse is not blown,
• wherein said first current source comprises a first p-type field effect transistor having a first gate width and said second current source comprises a second p-type field effect transistor having a second width, and
• wherein said first gate width is less than said second gate width so that said first current is less than said second current;
• and
• comparing a first voltage at said first input to a second voltage at said second input to determine whether said at least one first fuse is blown, and
• wherein said at least one first fuse comprises a plurality of first fuses and wherein said method further comprises blowing said first fuses on demand by providing a blow voltage sufficient to cause a third current passing over said first fuses to become high enough to blow said first fuses and by allowing said third current to flow through each of said first fuses sequentially.