Abstract:

A narrow band filter used in IRDA IC whose central frequency and band width can be orthogonally modulated was designed  using the CSMC 0.6μm BiCMOS process.  The narrow band filter consisted  of bipolar OTA cells. With thesimulation of HSPICE, the conclusion could be obtained that the central frequency of this filter was 38.02kHz, the band width was 3.92kHz, and the central frequencyand the bind width could be orthogonally modulated, which can represent the outstanding capability of this filter.

Key words: narrow band filter; OTA cell; orthogonal modulation