scholarly journals Mismatch Insensitive Voltage Level Shifter Based on Two Feedback Loops

Electronics ◽  
2020 ◽  
Vol 9 (9) ◽  
pp. 1391
Author(s):  
Zushuai Xie ◽  
Zhiqiang Wu ◽  
Jianhui Wu

This paper presents a voltage level shifter (VLS) based on two feedback loops. The complementary feedback signals in the high voltage domain are re-used to assist voltage conversion and the complementary phase in the low voltage domain is not required. Unlike the conventional VLS, which depends on the pull-up network and pull-down network to achieve level shift, the transitions of both high-to-low and low-to-high of the proposed VLS are undertaken by two different feedback loops, respectively. Implemented in a standard 180 nm CMOS process, post-layout Monte Carlo (MC) simulations from 4000 points under mismatch variation show that the dynamic power (DP) and the propagation delay (PD) of the proposed VLS are 105.3 nW and 2.0 ns, respectively, at an input voltage VIN = 0.4 V with input frequency fin = 0.1 MHz. Meanwhile, the excellent normalized standard deviation of DP and PD is obtained with the proposed scheme. The temperature range for normal operation is from −20 °C to 85 °C.

Energies ◽  
2020 ◽  
Vol 13 (20) ◽  
pp. 5501
Author(s):  
Harald Dillersberger ◽  
Bernd Deutschmann ◽  
Douglas Tham

This paper presents a novel converter for boosting the low-voltage output of thermoelectric energy harvesters to power standard electronic circuits. The converter can start up from a fully depleted state of the system off a bipolar ±13 mV input and can boost it to output voltages of up to 5 V. The converter comprises two transformers, one for each polarity that are multiplexed between an oscillator (used during startup) and a flyback converter (used during normal operation). To eliminate leakage currents in the input stage, the unused converter is completely turned off at startup and both converters are automatically shut off if the input power is found to be too low. Measurement results of the converter designed in a 180 nm CMOS process demonstrate a peak end-to-end conversion efficiency of 85% and nearly perfect impedance matching over the full input voltage range. This is the first time that a converter for ultra-low bipolar input voltages achieves the same performance as a unipolar converter.


2020 ◽  
Vol 17 (6) ◽  
pp. 803-809
Author(s):  
Vaithiyanathan D. ◽  
Megha Singh Kurmi ◽  
Alok Kumar Mishra ◽  
Britto Pari J.

Purpose In complementary metal-oxide-semiconductor (CMOS) logic circuits, there is a direct square proportion of supply voltage on dynamic power. If the supply voltage is high, then more amount of energy will be consumed. Therefore, if a low voltage supply is used, then dynamic power will also be reduced. In a mixed signal circuit, there can be a situation when lower voltage circuitry has to drive large voltage circuitry. In such a case, P-type metal-oxide-semiconductor of high-voltage circuitry may not be switched off completely by applying a low voltage as input. Therefore, there is a need for level shifter where low-voltage and high-voltage circuits are connected. In this paper the multi-scaling voltage level shifter is presented which overcomes the contention problems and suitable for low-power applications. Design/methodology/approach The voltage level shifter circuit is essential for digital and analog circuits in the on-chip integrated circuits. The modified voltage level shifter and reported energy-efficient voltage level shifter have been optimally designed to be functional in all process voltage and temperature corners for VDDH = 5V, VDDL = 2V and the input frequency of 5 MHz. The modified voltage level shifter and reported shifter circuits are implemented using Cadence Virtuoso at 90 nm CMOS technology and the comparison is made based on speed and power consumed by the circuit. Findings The voltage level shifter circuit discussed in this paper removes the contention problem that is present in conventional voltage level shifter. Moreover, it has the capability for up and down conversion and reduced power and delay as compared to conventional voltage level shifter. The efficiency of the circuit is improved in two ways, first, the current of the pull-up device is reduced and second, the strength of the pull-down device is increased. Originality/value The modified level shifter is faster for switching low input voltage to high output voltage and also high input voltage to low output voltage. The average power consumption for the multi-scaling voltage level shifter is 259.445 µW. The power consumption is very less in this technique and it is best suitable for low-power applications.


2021 ◽  
Author(s):  
Darshil Patel

Low noise, high PSRR and fast transient low-dropout (LDO) regulators are critical for analog blocks such as ADCs, PLLs and RF SOC, etc. This paper presents design of low power, fast transient, high PSRR and high load-regulation low-dropout (LDO) regulator. The proposed LDO regulator is designed in 180nm. CMOS process and simulated in LTSpice and Cadence platform. The LDO proposed can support input voltage range up to 5V for loading currents up to 230mA. Measurements showed transient time or set-up time of less than 22µs, PSRR of ~66dB at 100kHz and >40dB at 1MHz and 0.8535mV of output voltage variation for a 0-230mA of load variation.


2021 ◽  
Author(s):  
Darshil Patel

Low noise, high PSRR and fast transient low-dropout (LDO) regulators are critical for analog blocks such as ADCs, PLLs and RF SOC, etc. This paper presents design of low power, fast transient, high PSRR and high load-regulation low-dropout (LDO) regulator. The proposed LDO regulator is designed in 180nm. CMOS process and simulated in LTSpice and Cadence platform. The LDO proposed can support input voltage range up to 5V for loading currents up to 230mA. Measurements showed transient time or set-up time of less than 22µs, PSRR of ~66dB at 100kHz and >40dB at 1MHz and 0.8535mV of output voltage variation for a 0-230mA of load variation.


2019 ◽  
Vol 29 (04) ◽  
pp. 2020002
Author(s):  
Yasin Bastan ◽  
Parviz Amiri

A digital-based Pseudo-differential Schmitt trigger is proposed in this paper which is suitable for ultra-low voltages and pure digital integrated circuit technologies. The proposed Schmitt trigger is implemented according to the design procedure of an analog Schmitt trigger and only using digital CMOS inverters. It is composed of a differential comparator consisting of two CMOS inverters and a cross-coupled inverter pair positive feedback which has simultaneously two outputs of noninverting and inverting. The proposed circuit is the only digital Schmitt trigger which operates in differential mode and its hysteresis center can be changed by the input voltage. Implementing the circuit in digital-based allows the proposed Schmitt trigger to operate in 0.4[Formula: see text]V ultra-low-voltage. Principle operation of the proposed circuit is discussed theoretically and using formulas and its performance is verified by simulation in TSMC 0.18[Formula: see text][Formula: see text]m CMOS process. The proposed circuit occupies only [Formula: see text][Formula: see text][Formula: see text]m2 chip area due to the very low number of transistors. The hysteresis width of the proposed Schmitt trigger is 205[Formula: see text]mV and consumes only 6.64[Formula: see text]nW power.


IEEE Access ◽  
2020 ◽  
Vol 8 ◽  
pp. 145577-145585
Author(s):  
Xi Chen ◽  
Ting Zhou ◽  
Jiajie Huang ◽  
Guoxing Wang ◽  
Yongfu Li

2013 ◽  
Vol 22 (04) ◽  
pp. 1350017 ◽  
Author(s):  
GUANZHONG HUANG ◽  
PINGFEN LIN

A 6-bit low-voltage power-efficient flash analog-to-digital converter (ADC) is presented in this paper. The proposed ADC replaces the conventional voltage comparator with a new approach in the time-domain. The reference voltages and the analog input voltage are converted to digital signal in a form of different pulse widths by using a pulse-width-modulation (PWM) circuit. Consequently, the comparison is achieved by checking the sequence of the pulse rising edges rather than amplifying and latching the voltage difference. The total input capacitance of the proposed ADC is as small as tens of femto-farads, resulting in much less demand for the front-end buffer and the sampling switch. In addition, an implementation of the digital foreground calibration helps to get rid of the nonmonotonic comparison thresholds due to mismatch. The calibration operates with the adaptive comparison threshold by tuning the modulation level of the PWM. The intermediate Gray code conversion increases the bubble tolerance by 1LSB. This digital-circuit-heavily-involved ADC has been designed and simulated in a 65 nm CMOS process, achieving 35.24 dB signal-to-noise-and-distortion-ratio (SNDR) at a sampling rate of 125 MS/s while consuming 803 μW from 1 V power supply. As a result, the figure of merit (FoM) is as low as 136 fJ/conversion-step.


Sign in / Sign up

Export Citation Format

Share Document