A High-Speed 6-Bit ADC Using SiGe HBT

摘要

This paper describes the design and performance of a high-speed6-bit ADC using SiGe HBT for measuring- instrument applications. Weshow that the Gummel-Poon model suffices for SiGe HBT modeling andthen we describe that the folding/interpolation architecture as wellas simple, differential circuit design are suitable for ADC designwith SiGe HBT. Mea- sured results show that the nonlinearity of theADC is within ±1/2LSB, and the effective bits are 5.2 bits at aninput frequency of 100 MHz and 4.2 bits at 200 MHz with 768 MS/s. Wealso de- scribe some design issues for folding/interpolation ADC.