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We present a wideband, low noise amplifier (LNA) implemented in a Silicon-Germanium Heterojunction Bipolar Transistor (SiGe HBT) technology. This SiGe LNA covers a frequency range of 8–16 GHz and achieves a peak gain of 17.5 dB at nominal bias and a peak OIP3 of 15.8 dBm at 10 GHz at nominal bias. The noise figure (NF) of the LNA is 4.5–8.1 dB across band, and it nominally consumes 4 mA from a 4 V supply. Samples were irradiated with 63.3 MeV protons to proton-equivalent doses ranging from 200 krad(Si) to 2 Mrad(Si). This LNA incorporates bias control “tuning-knobs” to enable bias tuning to mitigate for RF performance loss due to total dose exposure and process variation in performance metrics. The effectiveness of the tuning “knobs” to compensate for lost post-irradiated performance was investigated. It was found that the LNA performance can be restored with the use of the tuning knobs with a performance tuning algorithm. [ABSTRACT FROM AUTHOR]

Abstract-We investigate the single-event transient (SET) response of bandgap voltage references (BGRs) implemented in SiGe BiCMOS technology through heavy ion microbeam experiments. The SiGe BGR circuit is used to provide the input reference voltage to a voltage regulator. SiGe HBTs in the BGR circuit are struck with 36-MeV oxygen ions, and the subsequent transient responses are captured at the output of the regulator. Sensitive devices responsible for generating transients with large peak magnitudes (more than 5% of the dc output voltage) are identified. To determine the effectiveness of a transistor-layout-based radiation hardened by design (RHBD) technique with respect to immunity to SETs at the circuit level, the BGR circuit implemented with HETs surrounded by an alternate reverse-biased pn junction (n-ring RHBD) is also bombarded with oxygen ions, and subsequent SETs are captured. Experimental results indicate that the number of events causing transients with peak magnitude more than 5% above the dc level have been reduced in the RHBD version; however, with the inclusion of the n-ring RHBD, new locations for the occurrence of transients (albeit with smaller peak magnitude) are created. Transients at the transistor-level are also independently captured and are presented. It is demonstrated that while the transients are short at the transistor level (ns duration), relatively long transients are obtained at the circuit level (hundreds of nanoseconds). In addition, the impact of the SET response of the BGR on the performance of an ultra-high-speed 3-bit SiGe analog-to-digital converter (ADC) is investigated through simulation. It is shown that ion-induced transients in the reference voltage could eventually lead to data corruption at the output of the ADC. [ABSTRACT FROM AUTHOR]