Design of a 10 MHz Transimpedance Low-Pass Filter with Sharp Roll-Off for a Direct Conversion Wireless Receiver
Abstract
A fully-differential base-band transimpedance low-pass filter is designed for use
in a direct conversion wireless receiver. Existing base-band transimpedance amplifiers
(TIA) often utilize single-pole filters which do not provide good stop-band rejection and
may even allow the filter to saturate in the presence of large interferers near the edge of
the pass-band. The designed filter is placed in parallel with an existing single-pole TIA
filter and diverts stop-band current signals away from the existing filter, providing added
rejection and safeguarding the filter from saturating. The presented filter has a
bandwidth of 10 MHz, achieves 35 dB rejection at 50 MHz (25 dB in post-layout
simulations), and can process interferers as large as 10 mA. The circuit is designed in
Jazz 0.18 m CMOS technology, and it is shown, using macromodels, that the design is
scalable to smaller, faster technologies.
Citation
Hodgson, James K. (2009). Design of a 10 MHz Transimpedance Low-Pass Filter with Sharp Roll-Off for a Direct Conversion Wireless Receiver. Master's thesis, Texas A&M University. Available electronically from https : / /hdl .handle .net /1969 .1 /ETD -TAMU -2009 -05 -266.