Reducing indirect programming mismatch due to oxide-traps using dual-channel floating-gate transistors

This paper presents a dual-channel architecture for floating-gate transistors that can alleviate the detrimental effects of oxide-traps seen in indirect programming techniques. The proposed transistor consists of four input/output ports that allow multiple paths for drain currents to flow and yet share the same gate-oxide and poly-silicon gate. As a result, one pair of the ports can be used for indirect programming, whereas the other pair can be actively connected to other analog circuits. Compared with the existing approaches for floating-gate programming, the proposed technique avoids disruption of the circuit operation and eliminates the effect of oxide-traps as well. In this paper we present measured results obtained from a dual-channel floating-gate current reference which has been fabricated in a 0.5-mum standard CMOS process.