Duane C. Howard

A New Self-Healing Methodology for RF Amplifier Circuits Based on Oscillation Principles

This paper proposes a novel self-healing methodology for embedded RF Amplifiers (LNAs) in RF sub-systems. The proposed methodology is based on oscillation principles in which the Device-under-Test (DUT) itself generates the output test signature with the help of additional circuitry. The self-generated test signature from the DUT is analyzed by using onchip resources for testing the LNA and controlling its calibration knobs to compensate for multi-parameter variations in the LNA manufacturing process. Thus, the proposed methodology enables self-test and self-calibration of RF circuits without the need for external test stimulus. The proposed methodology is demonstrated through simulations as well as measurements performed on a RF LNA.

An 8–16 GHz SiGe Low Noise Amplifier With Performance Tuning Capability for Mitigation of Radiation-Induced Performance Loss

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.

A 6–20 GHz Adaptive SiGe Image Reject Mixer for a Self-Healing Receiver

A wideband (6-20 GHz) Silicon-Germanium (SiGe) adaptive image-reject mixer with an intermediate frequency (IF) of 1.8 GHz is presented. The mixer can be “self-healed” to deliver consistent performance by nullifying the effects of process variations, environmental changes, or aging. Various performance metrics of the mixer can also be adapted to different specifications across multiple frequency bands. A conversion gain greater than 15 dB, an image rejection ratio (IRR) exceeding 35 dB, and an output 1-dB compression point greater than 10 dBm, were obtained in measurement. An automated self-healing procedure is developed and shown to be effective for improving the measured performance of the mixer. The mixer was fabricated in a 150 GHz peak fT, 200 nm SiGe BiCMOS process technology and consumes 215 mA of current operating off a 4 V rail.

A 3–20 GHz SiGe HBT ultra-wideband LNA with gain and return loss control for multiband wireless applications

We present an ultra-wideband, Low Noise Amplifier (LNA) implemented in Silicon-Germanium Heterojunction Bipolar Transistor (SiGe HBT) technology. This SiGe LNA is broadband, covering the frequency range of 3–20 GHz, and achieves a peak gain of 21.3 dB. The SiGe LNA exhibits a Noise Figure (NF) of 4.2–5.2 dB across an 8–18 GHz band and consumes 35.2 mA from a 3.3 V supply.

Evaluating the Effects of Single Event Transients in FET-Based Single-Pole Double-Throw RF Switches

The impact of single event transients (SETs) on single-pole double-throw (SPDT) RF switch circuits designed in a commercially-available, 180 nm second-generation SiGe BiCMOS (IBM 7HP) technology is investigated. The intended application for these SPDT RF switches requires a 1 GHz to 20 GHz band of operation, relatively low insertion loss (<; 3.0 dB at 20 GHz), and moderate isolation (> 15 dB at 20 GHz). Two-photon absorption experiment results reveal that the SPDT switches are vulnerable to SETs due to biasing effects as well as the triple-well (TW) nFETs, which are found to be more sensitive to SETs than bulk nFETs. From these results, potential implications are discussed and mitigation strategies are proposed. To verify one of the proposed mitigation techniques, SPDT switches were also designed in a 180 nm twin-well SOI CMOS (IBM 7RF-SOI) technology. A different biasing technique is implemented to help improve the SET response. The fabricated SOI SPDT switches achieve an insertion loss of <; 1.04 dB at 20 GHz and > 21 dB isolation at 20 GHz. For this circuit, no transients were observed even at very high laser energies (≈ 5 nJ).

A SiGe 8–18-GHz Receiver With Built-In-Testing Capability for Self-Healing Applications

A wideband (8-18 GHz) built-in test receiver in silicon-germanium technology is presented. The receiver chain consists of a low-noise amplifier (LNA), an image-reject mixer, on-chip automatic gain control ring oscillator sources that are used to provide test signals of a predefined amplitude, and control circuitry in the form of digital-to-analog converters and data registers. Both the LNA and the mixer circuit blocks incorporate tuning knobs to enable tuning of RF metrics to ensure consistent performance and mitigate the negative effects of process, voltage, and temperature variations, aging, and damage from extreme environments such as ionizing radiation. A maximum post-healed gain greater than 30 dB, an image rejection ratio exceeding 30 dB, output third-order intercept point greater than 8 dBm, and noise figure less than 9 dB are obtained in measurement. An automated healing algorithm was developed and shown to be effective at improving the overall performance of the receiver. The receiver was fabricated in an 0.18- μm SiGe BiCMOS process with a peak fT of 150 GHz, and consumes 240-260 mA from a 4-V supply.

Impact of Total Ionizing Dose on a 4th Generation, 90 nm SiGe HBT Gaussian Pulse Generator

We investigate the effects of total ionizing dose (TID) on a Gaussian pulse generator implemented in IBMs new 9HP SiGe BiCMOS platform, which combines 300 GHz fT SiGe HBTs and 90 nm CMOS. Total dose effects were examined using a 10-keV X-ray source. The effects of TID on the performance of the pulse generator were investigated with the pulse generator exhibiting a tpw variation of less than 7% for total dose of up to 3.0 Mrad. This circuit is intended for low-power autonomous high-altitude and space-based imaging radars.

A UWB SiGe LNA for multi-band applications with self-healing based on DC extraction of device characteristics

We present an ultra-wideband, Low Noise Amplifier (LNA) implemented in a Silicon-Germanium Heterojunction Bipolar Transistor (SiGe HBT) technology. This SiGe LNA covers a frequency range of 8–18 GHz and achieves a peak gain of 15.6 dB at nominal bias and a nominal OIP3 of 3 dBm at 13 GHz. The Noise Figure (NF) of the LNA is 3.6–7.9 dB across band, and it consumes 7 mA from a 3.3 V supply. This LNA incorporates bias control knobs for circuit ‘self-healing’ to compensate for process-induced (or other) variations in performance metrics. Process variations are detected using a companion source measure unit (SMU) test circuit that gathers DC device information to determine the healing to be applied.

An adaptive, wideband SiGe image reject mixer for a self-healing receiver

A wideband (6–20 GHz) SiGe adaptive image reject mixer with an IF bandwidth of more than 1.8 GHz is presented. The mixer can be “self-healed” to deliver consistent performance across band by nullifying the effects of process variations, environmental changes or aging and can be adapted to different specifications. A conversion gain greater than 15 dB, an image rejection ratio (IRR) exceeding 35 dB and an output 1-dB compression point greater than 10 dBm were obtained in measurement. An automated self-healing procedure is shown to be effective for improving the measured performance of the mixer. The mixer was fabricated in a 150 GHz peak fT 200 nm SiGe BiCMOS process and consumes 215 mA of current operating off a 4 V rail.

A 34–110 GHz wideband, asymmetric, broadside-coupled Marchand balun in 180 nm SiGe BiCMOS technology

An asymmetric, broadside-coupled Marchand balun for wideband millimeter wave applications is presented. The balun based on the modified off-center frequency method achieves 34-110 GHz operation bandwidth and exhibits minimum insertion loss of 4.7 dB at 54 GHz. To the authors best knowledge, this is the widest operational bandwidth among the recently published millimeter wave baluns in silicon technology.