Patent ID: 6618311
Filing Date: 2003-09-09
Classification: G11C

Abstract:
A fuse state sensing circuit, comprising:a fuse coupled between a ground rail and a fuse state sensing node, the fuse state sensing node indicating a state of the fuse when rail voltage is provided to the fuse state sensing circuit; a capacitive element coupled to the fuse state sensing node, the capacitive element capable of providing a first amount of current to the fuse state sensing node when an initial voltage is supplied to the rail voltage, the capacitive element being configured to stop supplying the first amount of current upon reaching a threshold voltage of the capacitive element; and a keeper latch circuit coupled to the fuse state sensing node in parallel with the capacitive element, the keeper latch circuit capable of latching the state of the fuse state sensing node, wherein the keeper latch circuit stops supplying current to the fuse state sensing node when a predetermined rail voltage is reached if the fuse is intact, and wherein the keeper latch circuit continues to supply current to the fuse state sensing node when a predetermined rail voltage is reached and the fuse is blown.