Tse-Hung Wu

A 5.2 GHz 16 dB gain CMFB Gilbert downconversion mixer using 0.35 /spl mu/m deep trench isolation SiGe BiCMOS technology

A 16 dB conversion gain, IP/sub 1dB/=-21 dBm and IIP/sub 3/=-11 dBm Gilbert downconversion micromixer when RF=5.2 GHz and LO=5.17 GHz is demonstrated by using 0.35 /spl mu/m SiGe BiCMOS technology. The input return loss is better than 13 dB for frequencies up to 10 GHz. Active PMOS loads with common mode feedback to stabilize the bias points is used in the Gilbert mixer loads to increase the mixer gain. An IF NMOS differential amplifier converts the differential output into a single-ended output. SiGe HBTs possesses good device matches and the SiGe BiCMOS technology has deep trench isolation technique to improve the port to port isolation. Finally, an off-chip rat-race coupler provides balanced LO signals to facilitate isolation measurement. -66 dB LO-IF, -52 dB LO-RF and -24 dB RF-IF isolations for a downconversion micromixer are achieved.

A 5.2 GHz 47 dB Image Rejection Double Quadrature Gilbert Downconverter Using 0.35 μm SiGe HBT Technology

A 5.2 GHz 1 dB conversion gain, IP1 dB = -19 dBm and IIP3 = -9 dBm double quadrature Gilbert downconversion mixer with polyphase filters is demonstrated by using 0.35 μm SiGe HBT technology. The image rejection ratio is better than 47 dB when LO=5.17 GHz and IF is in the range of 15 MHz to 45 MHz. The Gilbert downconverter has four-stage RC-CR IF polyphase filters for the image rejection. Polyphase filters are also used to generate LO and RF quadrature signals around 5 GHz in the double quadrature downconverter.

A monolithic SiGe heterojunction bipolar transistor gilbert upconverter with inductor-capacitor current mirror load and lumped-element rat-race balun

A 5.2 GHz upconversion Gilbert mixer with single-ended intermediate frequency (IF), local oscillator (LO), and RF ports is demonstrated using 0.35 µm SiGe heterojunction bipolar transistor (HBT) technology. The upconverter has a single-ended IF port. In addition, a lumped-element rat-race hybrid is inserted in the LO input stage to maintain balanced LO signals. The physics of the lumped-element rat-race is discussed in this paper. A passive LC current mirror is used to convert the mixers differential outputs into a single-ended output and double the output current. The design methodology of the LC current mirror and a new approach to improve the power gain with the output buffer are developed in this paper. The fully matched Gilbert upconverter has the conversion gain of -1 dB, OP1 dB of -10 dBm and OIP3 of 6 dBm when input IF=300 MHz, LO=4.9 GHz and output RF=5.2 GHz. The LO-IF isolation is -36 dB and the LO-RF isolation is -39 dB. The supply voltage is 3.3 V, the current consumption is 11.5 mA, and the die size is 0.98×0.83 mm2 with six integrated on-chip inductors.

A fully integrated 5.2 GHz SiGe HBT upconversion micromixer using: lumped balun and LC current combiner

A small and compact 5.2 GHz upconversion Gilbert micromixer using 0.35 μm SiGe HBT technology is demonstrated in this paper. The upconversion micromixer has a broadband matched single-ended IF input port. A lumped-elementrat-race hybrid is inserted in the LO input stage to maintain LO phase accuracy. A passive LC current combiner is used to convert the micromixer differential output into a single-ended output and double the output current. Thus, the IF port, LO port and RF port of the upconverter are single-ended, and the stand-along upconverter is suitable for hybrid RF system applications. The fully matched high linearity micromixer has the conversion gain of-1 dB, OP 1 d B of -10 dBm, OIP 3 of 6 dBm when input IF=300 MHz, LO=4.9 GHz and output RF=5.2 GHz. The IF input return loss is better than 10 dB for frequencies up to 20 GHz while the RF output return loss is better than 13.5 dB for frequencies up to 20 GHz. The supply voltage is 3.3 V, the current consumption is 11.5 mA, and the die size is 0.98x0.83 mm 2 with 6 integrated on-chip inductors.

Compact GaInP/GaAs HBT Gilbert Mixers With On-Chip Active LO Balun

A Gilbert micromixer is demonstrated in this paper using GalnP/GaAs HBT technology. The RF, LO, and IF ports of the micromixer are all single-ended using the on-chip active LO balun. The port-to-port isolation has its best performance when the LO signal is balanced. The stand-along micromixer is suitable for hybrid RF system applications. The fully matched high linearity micromixer has the conversion gain of 12 dB, IPIdB of-9 dBm, IIP3 of 1 dBm when input IF=300 MHz, LO=3.5 GHz and output RF=3.8 GHz.

General purpose RFICs using 0.35 um SiGe BiCMOS technology

This paper presents an overview of several 5 GHz general purpose RFICs implemented using 0.35 um SiGe BiCMOS technology by our research group. These RFICs include emitter-inductively-degenerated cascode LNA, shunt-series shunt-shunt dual feedback wideband amplifier, common mode feedback Gilbert down-converter, Gilbert up-converter with EC current mirrors and Gilbert down-converter with polyphase filters for image rejection.