A 5-8 Gb/s low-power transmitter with 2-tap pre-emphasis based on toggling serialization

We demonstrate a low-power wireline transmitter with 2-tap pre-emphasis in which serialization is achieved by toggling serializer with data transition information extracted from parallel input data. This novel technique of serialization provides significantly reduced power consumption since it does not need the short pulse generation block required in the conventional serializer. In addition, the same data transition information can be directly used for implementing 2-tap preemphasize and, consequently, the need for the additional serializer required in the conventional pre-emphasis circuits can be eliminated, resulting in further reduced power consumption. A prototype transmitter realized in 65nm CMOS technology achieves energy efficiencies of 0.202 pJ/bit at 5 Gb/s and 0.3 pJ/bit at 8 Gb/s for 150 mVpp,d output voltage swing without preemphasis, and 0.252 pJ/bit at 5 Gb/s and 0.333 pJ/bit at 8 Gb/s with 2-tap pre-emphasis providing 6-dB equalization gain. To the best of our knowledge, these are the lowest energy efficiencies achieved for wireline transmitters realized in 65nm CMOS technology. Keywords—transmitter, low power transmitter, energy efficient, pre-emphasis, data transition information, toggling serializer