Gradient sensitivity reduction in current mirrors with non-rectangular layout structures

A new current mirror structure using a non-rectangular dual-drain device with a shared channel to reduce the matching sensitivity to linear parameter gradients is introduced. The new structures are compared with conventional common centroid layouts for threshold voltage gradients at all angles across the active area of a mirror. Results show that in some applications, significant improvement in matching characteristics with the proposed non-rectangular structures over what is achievable with conventional layout techniques can be achieved.