Non volatile programmable flip-flop with predefined initial state, especially for memory redundancy circuit.

摘要

Current can pass from the voltage rail down two parallel paths (T1,T3,TGF1; T2,T4,TGF2). The second path has an extra transistor (T8) in series. in the non- programmed state, the extra transistor pushes the voltage in its path higher. This is reinforced by connections from the transistor grids to the opposite paths. the output logic state output (OUT) thus remains at 1. If the path through the extra transistor is blocked, the transistor connected to the output logic conducts, allowing an upper connection (INV) to the parallel paths to be set to zero. A transistor in the opposite path (TGF1) is then set to non-conducting and the imbalance to the opposite parallel path is reinforced. Thus a two state output is produced, with no permanent current flow in the stable states.