A monotonic digitally controlled delay element

• Published in: IEEE journal of solid-state circuits 2005-11, Vol.40 (11), p.2212-2219
• Main Authors: Maymandi-Nejad, M., Sachdev, M.
• Format: Article
• Language: English
• Subjects: Applied sciences; Architecture; Circuit properties; Circuit testing; Circuits of signal characteristics conditioning (including delay circuits); CMOS; CMOS integrated circuits; CMOS technology; Delay; delay circuits; delay-locked loops; Design. Technologies. Operation analysis. Testing; Digital; Digital circuits; Digital control; Electric, optical and optoelectronic circuits; Electronic circuits; Electronics; Empirical equations; Equations; Exact sciences and technology; Integrated circuits; Inverters; Mathematical analysis; MOSFETs; programmable delay; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices; Switches; test; Vectors (mathematics); Very large scale integration; Voltage; Voltage control
• ISSN: 0018-9200; 1558-173X
• DOI: 10.1109/JSSC.2005.857370

A monotonic digitally controlled delay element (DCDE) is implemented in the 0.18 /spl mu/m CMOS technology. In this paper, the design procedure of the new architecture and measurement results are reported. The delay of the DCDE changes monotonically with respect to the digital input vector. The monotonicity is one of the important features of this new architecture. Due to its monotonic behavior, the design of the DCDE is rather straightforward. The DCDE can be analyzed by a simple set of empirical equations with reasonable accuracy and can be made more tolerant to process, temperature, and supply voltage variations. The implemented delay element provides a delay resolution of as low as 2 ps and consumes 170 /spl mu/W to 340 /spl mu/W static power depending on the digital input vector.