We present the results of measurements of the scattering parameters of microstrip amplifiers MSAs based on the dc superconducting quantum interference device. The amplifier input impedance is poorly matched to typical transmission line impedances, resulting in high input return loss around 2 dB. We show that negative feedback can lower the MSA input impedance to achieve a robust match to 50 . I...

One of the most suitable ways of distributing a resistive sensor array for reading is an array with M rows and N columns. This allows reduced wiring and a certain degree of parallelism in the implementation, although it also introduces crosstalk effects. Several types of circuits can carry out the analogue-digital conversion of this type of sensors. This article focuses on the use of operationa...

A novel topology for a high gain two-stage amplifier is proposed. The proposed circuit is designed in a way that the non-dominant pole is at output of the first stage. A positive capacitive feedback (PCF) around the second stage introduces a left half plane (LHP) zero which cancels the phase shift introduced by the non-dominant pole, considerably. The dominant pole is at the output node which m...

Generating droplets of uniform volume is essential for the digital microfluidics systems, which use droplets as basic fluidic units. Recently we have shown that high uniformity (±%2) can be achieved by new firing sequence [1]. We have also confirmed accurate on-chip capacitive measurement of droplet volumes [1,2]. In the current paper, we develop feedback control system to defeat the random unc...

In this paper we present a 2 input analog Current-Starved Pseudo-Floating Gate (CSPFG) inverter with capacitive feedback. The analog CSPFG inverter suppresses low frequencies due to the active, local feedback. This inverter can be used in designing filters where a narrow band pass or reject is the main goal. Typical applications are detection of high frequency components in sensor signals, i.e....

Piezoelectric transducers are known to exhibit less hysterisis when driven with current or charge rather than voltage. Despite this advantage, such methods have found little practical application due to the poor low frequency response of present current and charge driver designs. This paper introduces the compliance feedback current driver containing a secondary voltage feedback loop to prevent...

A novel low noise trans-impedance amplifier is proposed using low cost 0.18 µm CMOS technology. A resistive-capacitive feedback is used to extend the bandwidth of the amplifier. As the structure is inductor less, it is suitable for low cost integrated optical interconnects. In this paper Improved Particle Swarm Optimization have applied to determine optimal trans-resistance and noise of propose...

A modified frequency compensation technique is proposed for low-power area-efficient three-stage amplifiers driving medium to large capacitive loads. Coined hybrid cascode feedforward compensation (HCFC), the total compensation capacitor is divided and shared between two internal high-speed feedback loops instead of only one loop as is common in prior art. Detailed analysis of this technique sh...

Compound semiconductor detectors such as CdTe, CdZnTe, HgI2 and TlBr are known to exhibit large variations in their charge collection times. This paper considers the effect of such variations on the measurement of induced charge pulses by using resistive feedback charge-sensitive preamplifiers. It is shown that, due to the finite decaytime constant of the preamplifiers, the capacitive decay dur...

A continuous-time accelerometer interface is feasible when a high dynamic range together with a wide signal band is required. In this paper the implementation of a continuous-time force-feedback loop for a capacitive sensor element with a full-scale signal of ±1.5 g is presented. The interface is measured to attain a noise equivalent acceleration (NEA) density of 500 ng/ √ Hz at 30 Hz for the o...