CXD1958Q

The CXD1958Q is an integrated TCM/QAM demodulator for MMDS systems using the DAVIC MMDS standard. This highly integrated device incorporates an internal 8-bit ADC, image rejection and root-raised cosine filters, all-digital symbol timing recovery PLL, adaptive decision feedback equalizer (DFE) with 10 feedforward and 30 feedback taps, 4-D TCM decoder, and DAVIC/DVB compliant forward error correction comprising (204,188) Reed Solomon decoder, a programmable de-interleaver with I = 12 and I = 204, and a de-randomiser. All internal clocks are generated from a single external 30MHz reference crystal.

Device functionality CXD1958Q also includes 3-wire bus interface for configuring up to 2 tuner synthesizers, a sigma delta tuner IF-AGC output, a user programmable RFAFC sigma delta output, spectrum inversion of the received signal for tuner compatibility, and a highly configurable MPEG2-TS interface. An I2C bus interface provides on-board configuration and status monitoring of various functions including access to the equalizer tap values and constellation points. JTAG provides boundary scan test compatibility.