E. van der Heijden

A 19-23 GHz integrated LC-VCO in a production 70 GHz fT SiGe technology

Integrated LC-VCOs for microwave frequencies are widely used nowadays. Traditionally, a lot of attention is paid to optimize the quality factor of the integrated inductor and varactor. The active part of the oscillator, used to undamp the resonator circuit, is often implemented as a cross-coupled differential pair. Even with a near-loss-less resonator circuit, this cross-coupled pair inherently puts a limit to the maximum attainable oscillation frequency. We derive a relation for this maximum attainable frequency f/sub cross/, and demonstrate a 19-23 GHz integrated LC-VCO approaching this theoretical limit for our IC-technology.

RF figures-of-merit for process optimization

Today, transistor y-parameters are routinely being measured for the determination of the current-gain cut-off frequency f/sub T/ and the maximum oscillation frequency f/sub max/. In this paper, it is shown that a much wider use of y-parameter measurements can be made for the RF characterization of transistors. A method is presented to determine the small-signal behavior of actual RF circuit-blocks from the measurements of the y-parameters of the individual circuit components. This is applied to define additional RF figures-of-merit for basic building blocks of analogue and digital RF circuits. No equivalent transistor circuit or compact-model parameters are needed, which is important for giving quick feedback to process developers. This approach is illustrated on three basic RF circuit blocks using bipolar transistors.

15-27 GHz pseudo-noise UWB transmitter for short-range automotive radar in a production SiGe technology

Short-range radar is a technology that potentially can help to enhance road safety. Recently, in the USA as well as in Europe, frequency bands around 24 GHz have been opened up for automotive radar applications. This paper describes an ultra-wideband (UWB) transmit path in a production 0.25 /spl mu/m SiGe BiCMOS IC technology. The UWB signal is generated by means of biphase modulation of a 24 GHz carrier with a pseudo-noise data signal. When no digital modulation signal is applied, the IC can be used for FM-CW modulation. The transmit path supports pseudo-noise biphase modulation up to 2 Gb/s data rates and generates an unmodulated output power between 2 and 5 dBm differentially for frequencies between 15-27 GHz. The 0.80/spl times/0.66 mm/sup 2/ IC dissipates 168 mW from a 3.3V supply.

On-chip third-order band-pass filters for 24 and 77 GHz car radar

At microwave frequencies, the use of on-chip transmission lines as a design element becomes interesting due to the small wavelengths. At car radar frequencies, 24 and 77 GHz, the inductor can be implemented by a shorted stub, which is a transmission line, shorted at one end. This paper discusses the design, simulation and measurement results of two third-order band-pass filters with a pass-band from 22-29 GHz and 66-87 GHz, respectively. Both filters use shorted stubs as inductor. The area is small and the losses are low. We demonstrate an excellent agreement between calculated and measured filter characteristics

A SiGe-BiCMOS UWB Receiver for 24 GHz Short-Range Automotive Radar Applications

This paper presents a SiGe receiver IC for 24 GHz short-range automotive radar based on pseudo-noise code modulation. An on-chip 48 GHz LC-VCO plus frequency divider generate the 1/Q clock signals for zero-IF down-conversion. The 24 GHz output signal of the first frequency divider is available off-chip as carrier for the accompanying transmitter IC. The IC includes two LNAs with built-in single-ended to differential conversion. On-chip coplanar transmission lines on a ground shield are used extensively throughout the IC for distribution of RF and clock signals. The 1.5x1.7 mm2 receiver IC is implemented in a SiGe:C BiCMOS process with f tau/fmax = 130/140 GHz. The IC achieves a measured DSB noise figure below 7 dB across a 2.5 GHz DSB IF bandwidth, with a conversion gain of 39 dB.

16-26GHz Low Noise Amplifier for short-range automotive radar in a production SiGe:C technology

Short-range radar is a technology that potentially can help to enhance road safety. Recently, in the USA as well as in Europe, frequency bands around 24GHz have been opened up for automotive radar applications. This paper describes a low noise amplifier (LNA) in a production 0.25mum SiGe:C BiCMOS IC technology. The input and output impedances are matched to 50Omega (single-ended). The LNA has 11dB gain and 4.2dB noise figure at 24GHz and has excellent performance for frequencies between 16-26GHz. The 0.45times0.55mm2 IC dissipates 20mW from a 3.3V supply

Intermodulation distortion of a bipolar common-emitter amplifier with arbitrary emitter impedance and input matching network

In this paper, concise formulas for the intermodulation distortion of a bipolar common-emitter amplifier stage with arbitrary emitter impedance and input matching network are presented. These expressions provide quantitative insight in the influence of transistor properties, emitter degeneration and input power matching on distortion. Only a small set of measurable transistor parameters is needed. As examples, IIP3 is calculated for transistor only, transistor with emitter inductance, and transistor with emitter inductance and input matching circuit. Two transistors are compared: a double-poly Si transistor and a SiGe transistor in a similar process. A good agreement between analytical and numerical results is obtained.

A 35.2-37.6 GHz LC VCO in a 70/100 GHz f/sub T//f/sub max/ SiGe technology

An LC VCO circuit uses two cascaded emitter followers with resistive loads and combines negative resistance and output buffers. The VCO is particularly suited for frequencies above the limit of the cross-coupled differential pair, and a 35.2-37.6 GHz VCO achieves a phase noise of -105 dBc/Hz at 2 MHz from the carrier, in a 0.25 /spl mu/m production SiGe technology.

A 20-input 20-output 12.5Gb/s SiGe cross-point switch with less than 2ps RMS jitter

A cross-point switch IC in 0.25/spl mu/m SiGe technology for optical networking applications with 20 inputs and 20 outputs achieves an aggregate bandwidth of 250Gb/s. Jitter remains below 2ps RMS and is achieved using impedance matched on-chip signal transfer. The 36mm/sup 2/ IC dissipates 4W from a 2.5V supply.

Optimisation of LNA and PA circuits for a 1.8 V BiCMOS Si Bluetooth transceiver

In Bluetooth transceiver ICs, sharing transmitter output with receiver input pins is a major difficulty, often requiring off-chip switches. A design procedure optimising this interface is explained and demonstrated.