Optoelectronics Encoder for a 12-bit 1.28-GSPS Analog-to-Digital Converter

In this letter, a novel 1.28-gigasamples/s (GSPS) 12-bit optoelectronics analog-to-digital converter (ADC) system is presented. The ADC architecture encodes and multiplexes four 320-megasamples/s 12-bit time-interleaved quantized data into an aggregated 1.28-GSPS 12-bit digital signal in real time. All clock signals at frequencies of 1.28 GHz, and 640 and 320 MHz are generated from a single 320-MHz femtosecond laser source, thereby eliminating the need for external synchronization and control signals. A spurious-free dynamic range of value 80.6 dB, signal-to-noise and distortion ratio of value 54.33 dB, full-scale and zero-scale offset errors of value 2 least significant bits, and an effective number of bits of value 8.8 bits were all measured for the system.