NISCAIR Online Periodicals Repository Collection: IJPAP Vol.46(05) [May 2008]

High performance FGMOS-based low voltage current mirror

Title: High performance FGMOS-based low voltage current mirror

Authors: Manhas, Parshotam S; Sharma, Susheel; Pal, K; Mangotra, L K; Jamwal, K K S

Abstract: Current mirror (CM) is the basic building block in analog and mixed mode circuit design. For high performance analog circuit applications, the current transfer ratio, output impedance and output swing are the most important parameters to determine the performance of the current mirror. CM’s are important for analog integrated circuits because of their wide use as constant sources or active loads in amplifier stages. Their application is increasing continuously due to the developments in current-mode integrated circuit design. This paper describes a new Current Mirror proposed and optimized to provide high accuracy, very high impedance and output swing at very low voltages using floating gate MOSFET’s (FGMOS). The new mirror-High Performance Low Voltage Current Mirror (HPLVCM)- based on FGMOS has output current range of ~2 μ A to 500μA, high output impedance (785.4GΩ at 100µA and 64M Ω at 500μA), comparatively high bandwidth (631MHz) and low input compliance voltage (0.18V at 50μA and 0.45V at 500μA input current). The new design has been verified using PSpice simulations for 0.5μm CMOS technology at a supply voltage of ±0.75V. The error in current transfer is observed to be less than ±0.1%.

Page(s): 355-358

Evaluation of performance of GPS controlled rubidium clocks

Title: Evaluation of performance of GPS controlled rubidium clocks

Authors: Banerjee, P; Suri, A K; Suman; Chatterjee, Arundhati

Abstract: Global Positioning System (GPS) controlled rubidium clock systems are now being used widely for many precise timing applications. They also play the role of the reference time and frequency source in many laboratories. This demands the evaluation of performance of such clocks to assess their reliability. For this purpose, a special experimental campaign has been planned. The epoch time has been found to be reliable within 60 ns and frequency offset does not exceed few parts in 10-12. But the receiver takes few hours to achieve initial lock. Short-term stability in locked condition has been poorer than that of the rubidium clock in free running condition.

Page(s): 349-354

Optical properties of polyaniline doped PVC-PMMA thin films

Title: Optical properties of polyaniline doped PVC-PMMA thin films

Authors: Deshmukh, S H; Burghate, D K; Shilaskar, S N; Chaudhari, G N; Deshmukh, P T

Abstract: The optical transmission and UV-VIS absorption spectra have been recorded in the wavelength range 450-1000 nm for different compositions of polyaniline doped PVC-PMMA thin films. The absorption coefficient (⍺), optical energy gap (Eopt), refractive index (nօ), optical dielectric constant (Ɛ’), constant B and ratio of carrier concentration to the effective mass (N/m*) have been evaluated. The effects of doping percentage of polyaniline on these parameters have been discussed and the nonlinear behaviour for all the parameters are investigated.

Page(s): 344-348

Structural and optical studies of chemically prepared CdS nanocrystalline thin films

Title: Structural and optical studies of chemically prepared CdS nanocrystalline thin films

Authors: Barman, J; Sarma, K C; Sarma, M; Sarma, K

Abstract: Chemical bath deposition (CBD) technique has been used to prepare cadmium sulphide (CdS) thin films for various applications. Structural analysis of the films has been done by using Philips X-Pert PRO system analytical diffractrometer. Data collected by X-pert graphics software are used to identify the crystal structure, phase, grain size and lattice constant of films. XRD data have been obtained for optimizing the growth conditions for deposition. Ultra violet visible (UV-VIS) spectroscopy and scanning electron microscopy (SEM) are used to characterize the sample.

Page(s): 339-343