The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
In a classical PLL, the phase detector (PD) and charge pump (CP) noise is multiplied by N2, when referred to the VCO output, due to the divide-by-N in the feedback path. It often dominates the in-band phase noise and limits the achievable PLL jitter·power Figure-Of-Merit (FOM). A sub-sampling PLL uses a PD that sub-samples the high frequency VCO output with the reference clock. The PD and CP noise...
The fast adaptation of WiFi 802.11ac 256-QAM mode requires RF clocks with very low integrated phase error to deliver good EVM performance. On the other hand, smaller area and lower power are always desired for lower cost and longer battery life. This work presents a 28nm CMOS LO design for dual-band 802.11abgn/ac radio with overall architecture shown in Fig. 9.4.1. It addresses the aforementioned...
Digital intensive architectures allow for flexibly programmable frequency synthesis. Timing jitter and/or phase noise is an important quality criterion for synthesizers. This paper reviews fundamental limitations for jitter in digital frequency architectures, aiming at finding a basis to compare alternative architectures and optimize jitter performance. It motivates why the product of jitter variance...
As the latest product of Godson processor series, the Godson-3B processor is an 8-core high-performance general-purpose processor implemented in 65nm CMOS low-power general-purpose mixed process with 7 layers of Cu metallization. Godson-3B contains 582.6M transistors (including 4MB L2-cache) within 299.8mm2 area. The number of signal pins in Godson-3B is 654. The highest frequency of Godson-3B is...
A divider-less PLL exploits a phase detector that directly samples the VCO with a reference clock. No VCO sampling buffer is used while dummy samplers keep the VCO spur <;-56dBc. A modified inverter with low short-circuit current acts as a power efficient reference clock buffer. The 2.2 GHz PLL in 0.18 μm CMOS achieves -125dBc/Hz in-band phase noise with only 700 μW loop-components power.
Nondeterminism of multi-clock systems often complicates various system validation processes such as post silicon debugging and at-speed testing, which has brought many difficulties to system designers and testers. The major source of nondeterministic behaviors is clock domain crossing, because the clocks that determine the timing of events are sensitive to variations. In this paper, we propose a general...
In this paper, an optimum stage ratio (tapering factor) for a tapered CMOS inverter chain is derived to minimize the product of power dissipation and jitter variance due to device mismatch. Analysis shows that this optimum stage ratio (2.4) is lower than that of minimum delay (3.6) and minimum power-delay (6.35) product. This analysis is verified by simulation results using standard 180 nm as well...
This paper presents a 2.2 GHz clock-generation PLL. It uses a phase-detector/charge-pump (PD/CP) that sub-samples the VCO output with the reference clock. The PLL does not need frequency divider in locked state and achieves a low in-band phase noise values at low power.
This paper shows that, for a given power budget, a shift register based multi-phase clock generator (MPCG) generates less jitter than a delay-locked loop (DLL) equivalent when both are realized with current mode logic (CML) circuits and white noise is assumed. This is due to the factor that the shift register MPCG has no jitter accumulation from one clock phase to the other as in the DLL based MPCG...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.