1.5GHz fully differential latched current comparator with 20nA of sensitivity

Current comparison becomes critical in those data conversion systems where it is highly desirable to achieve speed without sacrificing either accuracy or power consumption. This paper presents a novel circuital solution to perform current comparison at very high speed. Furthermore, we deal with the comparator input offset causes proposing a mismatch aware design to get the desired accuracy. The comparator consists of a fully differential class-AB current input stage, two regenerative flip-flops, and an SR latch. We simulated the circuit in a 0.13mum technology with 1.2V supply voltage. The comparator speed can be pushed up to 1.5GHz achieving a current difference sensitivity up to 20nA and only 800muA of both static and dynamic current consumption