Room temperature cw operation of transverse mode stabilized 680-nm InGaAIP laser diodes have been achieved for the first time. A self-aligned structure was fabricated by two-step metalorganic chemical vapor deposition, which included the selective growth technique.

A new switches-capacitor immittance converter (SCIC) circuit based on the bilinear transformation is propose. The inductive (n+1)-terminal network is realized using in SCIC's and one capacitive (n+1)-terminal network. The SCIC consists of only one buffer, one op amp and three capacitors.

Mixed-signal LSIs promise to permit increased levels of integration, not only in voiceband but also in multi-GHz-band applications such as wireless communications and optical data links. This paper reviews the evolution of mixed-signal communications LSIs and discusses some of their design problems, including device noise and crosstalk noise. In the low-power and low-voltage designs emerging as new disciplines, the target supply voltage for voiceband LSIs is around 1 V, and even GHz-band circuits are approaching 2 V. MOS devices are expected to play an important role even in the frequency range over 100 MHz, in the area of wireless or optical communications circuits.

Thermal properties of InGaAlP laser diodes have been analyzed by computer simulation. Self-consistent analysis considering heat conduction, current distribution and optical waveguide mode has made it clear that there exist optimum structural parameters minimizing the threshold current.

A 2-GHz monolithic Si-bipolar logarithmic/ limiting amplifier is described. It features a waveform-dependent current phase shifter that compensates for the intrinsic dependence of unit-amplifier phase shifts on input signal amplitudes and layout techniques that minimize crosstalk in Si substrate. The amplifier dissipates 250 mW at a 3-V supply, which is less than 1/4 of that of previously reported ICs. The dynamic range of a received signal strength indicator (RSSI) is 60 dB and the limited-output phase deviation is less than 7 deg. at 2 GHz. Therefore, this amplifier is quite suitable for single-conversion transceivers for broadband wireless access systems.

RF integration, until recently the integration of active devices in conventional architectures suitable for discrete-component circuits, is now turning into full-integration based on new architectures developed specifically for an LSI technology. This paper reviews some of the key existing and emerging circuit techniques and discusses the serious problem of crosstalk. In order to develop miniature and low power RF transceivers, direct-conversion and monolithic VCO's will be further studied. Silicon bipolar technology will still be playing major role beyond the year 2,000, and CMOS will also be used in certain applications.