A 4 GHz fourth-order SiGe HBT band pass /spl Delta//spl Sigma/ modulator

Test results for a fourth-order band pass (BP) /spl Delta//spl Sigma/ modulator (/spl Delta//spl Sigma/M) are presented. The 0.5 /spl mu/m SiGe HBT design uses active LC resonators with Q enhancement and return-to-zero latches to drive the feedback DACs. The packaged circuit consumes 350 mW from a single 5 V supply when clocking at 4 GHz. Measured results indicate a maximum SNR of 53 dB, SFDR of 69 dB, and a dynamic range of 62 dB, all in a 4 MHz bandwidth.

[1]  William Martin Snelgrove,et al.  A linear active Q-enhanced monolithic LC filter , 1997, Proceedings of 1997 IEEE International Symposium on Circuits and Systems. Circuits and Systems in the Information Age ISCAS '97.

[2]  J. Cressler,et al.  Si/SiGe epitaxial-base transistors. I. Materials, physics, and circuits , 1995 .

[3]  William Martin Snelgrove,et al.  Switched-capacitor bandpass delta-sigma A/D modulation at 10.7 MHz , 1995, IEEE J. Solid State Circuits.

[4]  Omid Shoaei,et al.  Excess loop delay effects in continuous-time delta-sigma modulators and the compensation solution , 1997, Proceedings of 1997 IEEE International Symposium on Circuits and Systems. Circuits and Systems in the Information Age ISCAS '97.

[5]  Weinan Gao,et al.  A 950MHz Second-Order Integrated LC Bandpass AX Modulator , 1997 .

[6]  Weinan Gao,et al.  A 5-GHz SiGe HBT return-to-zero comparator for RF A/D conversion , 1996 .

[7]  Weinan Gao,et al.  A 950MHz Second-order Integrated LC Bandpass /spl alpha/spl sigma/ Modulator , 1997, Symposium 1997 on VLSI Circuits.