A Wide-Tuning Range, Amplitude-Locked Test Signal Source For Self-Healing, Mixed-Signal Electronic Systems

An integrated wideband amplitude-locked test signal source for "self-healing" and built-in-self-test (BIST) of multiband mixed-signal system-on-a-chip solutions is demonstrated. To the authors' knowledge, this work achieves the widest reported tuning range per unit die area compared to the state-of-the-art. The signal generator spans frequencies ranging from X to K band while occupying only 0.329 mm(2) of core die area. The oscillator core is based on a differential ring topology to achieve wide tuning capability. The amplitude-locked loop consists of a variable gain amplifier (VGA), a low power peak detector, and an opamp that doubles as a loop filter. The circuits were fabricated in a commercially-available 180 nm SiGe BiCMOS platform.