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An ultra-wideband 7-bit 5-Gsps analog-to-digital converter (ADC), fabricated in a 4-level interconnect, 0.8 µm Indium-Phosphide (InP) heterojunction bipolar transistor (HBT) technology, is presented. This monolithic folding/interpolating ADC includes a front-end master-slave sample and hold and a pipeline stage sample and hold. The chip achieves 6 effective number of bits (ENoB) Nyquist performance at a sample rate of S Gsps, while dissipating 8.4 W. Furthermore, an ENoB performance of greater than 5.7 is maintained at analog input frequencies up to 7.5 GHz. This effective resolution-bandwidth product performance is significantly higher than any other previously reported monolithic ADC with sample rate ≥3 Gsps. [ABSTRACT FROM AUTHOR]

High speed digital logic is essential in diverse applications such as optical communication, frequency synthesizers, and analog-digital conversion. Current research efforts indicate that technologies utilizing heterojunction bipolar transistors (HBT) are the preferred approach for systems operating at clock frequencies of 40 GHz and above (1-6). In this paper we report a novel InAlAs/InGaAs/InP double-HBT (DHBT) with a cantilevered base layer and undercut collector. We fabricated and demonstrated an 80 GHz 2:1 digital frequency divider, and a 5 GHz 8-bit phase/7-bit magnitude Direct Digital Synthesizer (DDS) chip with approximately 3000 transistors using this technology. [ABSTRACT FROM AUTHOR]