A 700-MHz 24-b pipelined accumulator in 1.2- mu m CMOS for application as a numerically controlled oscillator
To accomplish timing recovery/synthesis in high-speed communication systems, a 24-b numerically controlled oscillator (NCO) IC using a circuit design technique called true single-phase clock (TSPC) pipelined CMOS has been fabricated in a standard 1.2- mu m CMOS process. The device achieves a maximum tested input clock rate of 700 MHz, which results in an output frequency tuning range from DC up to 350 MHz with a 41.7-Hz tuning resolution and a peak-to-peak phase jitter of 1.4 ns. The 1.7-mm*1.7-mm IC dissipates 850 mW with a single 5-V supply, which is substantially lower than similar ECL and GaAs devices. >