Name
Title | ||
|---|---|---|
21.3 A 2GHz 130mW direct-digital frequency synthesizer with a nonlinear DAC in 55nm CMOS |
Abstract | ||
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Direct-digital frequency synthesizers (DDFSs) have been employed in many frequency-agile communication systems because of their wide bandwidth, fine frequency resolution, and fast frequency-hopping characteristics. Recent developments in DDFSs are towards enhancing performances through reduction of both complexity and power consumption [1-3]. The segmented nonlinear DAC (NLDAC) structures in [1,2] require additional coarse phase information for fine amplitude decoding with a complex decoder. Moreover, the quarter-sine-wave technique incorporated into the segmented NLDACs in [1,2] degrades spectral purity due to the need of the MSB shift DAC that introduces additional offset. Another scheme in [3] reduces complexity and power consumption by replacing the digital-based phase-to-amplitude converter with an analog-based converter, resulting in limited spectral purity. Unlike previous schemes, this work presents comprehensive enhancements in all key areas of a DDFS, the pipelined phase accumulator (PACC), digital decoder, and NLDAC as shown in Fig. 21.3.1. First, the low-power PACC with multi-level momentarily activated bias (M2AB) is presented to reduce power dissipation. Second, the coarse phase-based consecutive fine-amplitude grouping (C2FAG) scheme reduces the hardware complexity and the power consumption in digital decoder circuits. Third, the mixed-wave conversion topology (MCT) in the NLDAC improves the output spectral purity. |
Year | DOI | Venue |
|---|---|---|
2014 | 10.1109/ISSCC.2014.6757471 | Solid-State Circuits Conference Digest of Technical Papers |
Keywords | DocType | ISSN |
cmos integrated circuits,digital-analogue conversion,direct digital synthesis,c2fag scheme,cmos,ddfs,nldac structure,analog-based converter,coarse phase information,coarse phase-based consecutive fine-amplitude grouping scheme,complex decoder,digital decoder circuit,direct-digital frequency synthesizer,fast frequency-hopping characteristic,fine amplitude decoding,fine frequency resolution,frequency 25 ghz,frequency-agile communication system,hardware complexity,limited spectral purity,mixed-wave conversion topology,multilevel momentarily activated bias,nonlinear dac structure,phase-to-amplitude converter,pipelined phase accumulator,power 130 mw,power consumption,power dissipation,quarter-sine-wave technique,size 55 nm | Conference | 0193-6530 |
Citations | PageRank | References |
6 | 0.61 | 21 |
Authors | ||
6 | ||
Name | Order | Citations | PageRank |
|---|---|---|---|
| taegeun yoo | 1 | 22 | 3.03 |
| Yun-Hwan Jung | 2 | 21 | 2.77 |
| Hong Chang Yeoh | 3 | 22 | 2.49 |
| Yong Sin Kim | 4 | 19 | 5.45 |
| Sung-Mo Steve Kang | 5 | 1198 | 213.14 |
| Kwang-hyun Baek | 6 | 129 | 26.82 |