A new configuration realizing first-order canonical current processing all-pass filters based on current differencing buffered amplifier, a recently introduced active element, is proposed. Using this configuration, two types of first-order current-mode all-pass filters are derived. They employ only a single active element and a bare minimum number of passive components. No component-matching constrains are required. Because of the high performance of the current differencing buffered amplifier, they are suitable for wideband applications. The derived filters are cascadable because of their high output impedances and they use fewer active and/or passive components compared to their previously reported counterparts. As an application of the proposed first-order all-pass networks, a new current-mode high-Q bandpass filter, which offers a number of advantages over its counterparts, is also given.

Current-mode all-pass filters using current differencing buffered amplifier and a new high-Q bandpass filter configuration

A deep sub-nanosecond resolved CMOS pulse-shrinking delay element used in the time-to-digital converter (TDC) is proposed. The pulse shrinking capability of the element is controlled by the dimension ratio of the adjacent gates. This control mechanism is completely different from the bias adjustment adopted in the conventional pulse-shrinking element. Without the need of continuous calibration, the presented element possesses not only extremely fine resolution, small single-shot errors, low power consumption, but also good insensitivity to the supply voltage variation. Being fabricated with 0.35 /spl mu/m CMOS technologies, the TDC made of the new elements has been measured to have a resolution of 68 ps. The effective resolution only varies 1.5 ps for a rather large supply voltage range from 3.5 to 4.5 V. The size of the circuit is 0.35 mm/spl times/0.09 mm only, excluding the I/O pads. Under a single 3.3-V power supply, the static power dissipation, including the I/O pads, is 1 /spl mu/W. The average power consumption is measured to be merely 1.2 mW under a measurement rate of 100 ksps.

A CMOS pulse-shrinking delay element for time interval measurement

It is shown that two of the recently reported voltage mode and current mode current conveyor-based all-pass circuits can be generated from the well known single input op amp all-pass configuration. It is also found that two other voltage mode current conveyor-based all-pass circuits are related directly to the differential input op amp all-pass structure. Several new grounded capacitor all-pass circuits are introduced. A new universal biquad circuit which realizes complex poles and employs a single current conveyor is also given. PSpice simulation results are included.

Generation of current conveyor-based all-pass filters from op amp-based circuits

A novel first order all-pass section using a single second generation current conveyor is given. In addition the circuit uses two resistors and only one capacitor. The circuit is also realized with a translinear conveyor. The latter circuit uses only one external resistor and a capacitor. The proposed circuits are verified using PSPICE with attractive results.

Simple first order all-pass section using a single CCII

New current-mode sinusoidal oscillator circuits are presented. The proposed circuits use single four-terminal floating nullor and, at most, eight passive elements. Two of the oscillator circuits use grounded capacitors and enjoy the independent grounded-element control of the frequency of oscillation and the condition of oscillation. Experimental results are included.

Current-mode sinusoidal oscillators using single FTFN

A novel circuit configuration for the realisation of a current-mode first-order allpass filter using a single four-terminal floating nullor (FTFN) with a grounded capacitor, which is suitable for integrated circuit implementation, is proposed.

M. Higashimura

Papers

Current-mode allpass filter using FTFN with grounded capacitor