Circuit structure to measure outliers of process variation effects

Embodiments of the invention provide for integrated circuits for testing one or more transistors for process variation effects. According to an embodiment, the integrated circuit can include: a plurality of ring oscillator macro circuits, wherein each ring oscillator macro circuit includes two ring oscillators, a first multiplexer, and a first divide-by-two circuit; a multiplexer stage; a divide-by-two circuit stage; a second multiplexer; a second divide-by-two circuit; and frequency measurement circuit. According to another embodiment, the integrated circuit can include: a first shift register including a plurality of devices-under-test; a second shift register including a plurality of static latches; a first multiplexer configured to receive outputs from each of the plurality of DUTs; a second multiplexer configured to receive outputs from each of the plurality of static latches; and a comparator configured to compare an output from the first multiplexer with an output from the second multiplexer.