Abstract

The design, development and initial demonstration of a 4-bit 275-MS/s electrooptic A/D converter is reported. The device consists of a mode-locked Nd:YAG laser, an array of Ti-diffused LiNbO₃ interferometric modulators, a Ge avalanche photodiode and a special high-speed Si integrated circuit. This converter is of a type originally proposed by Taylor.¹ It depends on the periodic variation of the output of a guided-wave interferometric modulator with both voltage and electrode length to perform the conversion and the availability of short optical pulses from mode-locked lasers to perform the analog sampling. The Si integrated circuit acts as a comparator and serial-to-parallel converter. Two detailed studies of the design considerations for this converter have been reported.^2,3 There have been a number of reports of fundamental experiments^4-6 and devices have been reported^7-8 which operated at higher drive powers and at either lower speed or bit number than the device reported here.

© 1982 Optical Society of America