A novel current reference in 45nm cmos technology

In this paper a novel CMOS temperature and supply voltage independent current reference has been proposed. This design is based on the subtraction of two scaled version PTAT (proportional to absolute temperature) currents to provide a temperature independent current reference. The design was simulated with Spectre, and implemented in 45nm CMOS technology. Simulation results shows that the proposed current reference achieves temperature coefficient of 22ppm/0C against temperature variation of -400C –1200C and line sensitivity of 337ppm/V against supply variation of 0.6–1.8V, while consuming 135uW from 1.8V supply and occupying 5184um

A Microwatt low voltage bandgap reference for bio-medical applications

In this paper a microwatt low voltage bandgap reference suitable for the bio-medical application. The Present technique relies on the principle of generating CTAT and PTAT without using any (Bipolar Junction Transistor) BJT and adding them with a proper scaling factor for minimal temperature sensitive reference voltage. Beta multiplier reference circuit has been explored to generate CTAT and PTAT. Implemented in 45nm CMOS technology and simulated with Spectre. Simulation results shows that the proposed reference circuit exhibits 1.2% variation at nominal 745mV output voltage. The circuit consumes 16uW from 0.8V supply and occupying 0.004875mm2 silicon area

A CMOS blood cancer detection sensor based on frequency deviation detection

This paper proposes a technique to detect Leukaemia (blood cancer) based on the frequency modulation of a relaxation oscillator by changes in the dielectric constant of blood cells. A novel 16-bit frequency detector with a digital output has been proposed to detect the frequency difference between two oscillators based on healthy blood and Leukaemic blood. A circuit has been designed, to operate on a 1.2V supply, post layout simulations shows 0.35mA current consumption. The chip Area including pads~0.6mm∗0.45m

A compact high gain opamp for Bio-medical applications in 45nm CMOS technology

In this paper a low opamp compensation technique suitable for the bio-medical application has been proposed and intuitive explained the existing compensation techniques. The Present technique relies on the passive damping factor control rather power hungry damping. Implemented in 45nm CMOS technology and simulated with Spectre. Simulation results shows that 100dB dc gain, well compensated 25MHz bandwidth opamp while driving a 1pF capacitive load. Draws with 12uW power consumption from 1V supply and occupying 0.004875mm2 silicon area

A start-up assisted fully differential folded cascode opamp

This paper explains the hidden positive feedback in the two-stage fully differential amplifier through external feedback resistors, and possible DC latch-up during the amplifier start-up. The biasing current selection among the cascode branches have been explained intuitively, With reference to previous literature. To avoid the latch-up problem irrespective of the transistor bias currents a novel, hysteresis based start-up circuit is proposed. An 87dB, 250MHz unity gain bandwidth amplifier has been developed in 65nm CMOS Technology and post-layout simulations demonstrate no start-up failures out of 1000 Monte-Carlo (6-Sigma) simulations. The circuit draws 126uA from a 1.2V supply and occupies the 2184um2 area

A Novel Sub-1V Bandgap Reference with 17.1 ppm/0C Temperature coefficient in 28nm CMOS

Traditional Banba bandgap is very popular in deep sub-micron CMOS technologies because of its sub 1V output nature. But unfortunately, it won’t provide PTAT nature current and has several operating points, unlike two in the voltage mode BGR. This work analyzes the Banba circuit in a detailed way so that it’s easy to demonstrate multiple stable operating and lists some of its other shortfalls. This paper presents a novel sub-1V bandgap architecture, which can provide PTAT current and sub-1V output without having multiple operating points. A modified self-bias opamp has been proposed to minimize the systematic offset and its temperature drift. A prototype was developed in 28nm TSMC CMOS technology and post-layout simulation results were performed. Proposed  BGR targeted at 500mV works from 1V supply without having any degradation in the performance while keeping the integrated noise of 18.2µV and accuracy of 17.1ppm/0C, while the traditional Banba was resulting 23.4ppm/0C. Further, the circuit consumes  29.8µW of power and occupies 71*39µm2silicon area

B-cell receptor activation inhibits AID expression through calmodulin inhibition of E-proteins

Upon encountering antigens, B-lymphocytes can adapt to produce a highly specific and potent antibody response. Somatic hypermutation, which introduces point mutations in the variable regions of antibody genes, can increase the affinity for antigen, and antibody effector functions can be altered by class switch recombination (CSR), which changes the expressed constant region exons. Activation-induced cytidine deaminase (AID) is the mutagenic antibody diversification enzyme that is essential for both somatic hypermutation and CSR. The mutagenic AID enzyme has to be tightly controlled. Here, we show that engagement of the membrane-bound antibodies of the B-cell receptor (BCR), which signals that good antibody affinity has been reached, inhibits AID gene expression and that calcium (Ca2+) signaling is essential for this inhibition. Moreover, we show that overexpression of the Ca2+ sensor protein calmodulin inhibits AID gene expression, and that the transcription factor E2A is required for regulation of the AID gene by the BCR. E2A mutated in the binding site for calmodulin, and thus showing calmodulin-resistant DNA binding, makes AID expression resistant to the inhibition through BCR activation. Thus, BCR activation inhibits AID gene expression through Ca2+/calmodulin inhibition of E2A