A 0.190-pJ/bit 25.2-Gb/s/wire Inverter-Based AC-Coupled Transceiver for Short-Reach Die-to-Die Interfaces in 5-nm CMOS

This paper presents an Inverter-based AC-coupled Toggle (ISR-ACT) transceiver targeted for short-reach die-to-die communication over silicon interposer or similar high-density interconnect. The ISR-ACT's transmitter sends NRZ data through a small on-chip capacitor into the line. The receiver amplifies the low-swing pulses using a 1st-stage TIA to fully toggle the 2nd-stage output, where positive feedback to the input pad maintains the DC level on the line. Fabricated in a 5nm standard CMOS process, ISR-ACT link shows 0.66UI margin at 25.2Gb/s/wire on a 0.75V supply over a 1.2mm on-chip channel and demonstrates the potential to achieve 0.190pJ/bit.