Low-voltage Bandgap Reference Research Articles

Variation-aware automated design and optimization of sub-1V bandgap voltage reference

A robust systematic gm/ID-based design procedure for a CMOS low-voltage bandgap reference is introduced. The proposed approach is technology node independent, and it eliminates invoking the simulator in the loop by using precomputed lookup tables (LUTs) generated once. The proposed methodology is capable of addressing the impact of PVT corners and random mismatch. The proposed procedure is verified against Spectre simulations and yields very accurate results. Moreover, the bandgap reference automated synthesis procedure is fully vectorized, enabling the concurrent synthesis of multiple design points in a short time. As a result, large datasets can be generated to span the whole design space, which enables global optimization. Next, local optimization algorithms can be utilized to quickly determine the degrees of freedom of an optimal design point that meets a set of specifications. The speedup of the proposed methodology is around 140x compared to simulation-based optimization in addition to accomplishing better results.

Design of a High PSRR Low-pressure Bandgap Reference Source with Curvature Compensation

Based on the NUVOTON 0.35 μm BCD process, a low voltage bandgap reference with an input voltage of 5 V and output voltage of 0.6 V is designed in this paper. The traditional low-voltage bandgap reference output voltage has a large temperature coefficient and poor ability to suppress power supply fluctuations. In this paper, a circuit with high order compensation is proposed to reduce the temperature coefficient of the circuit, and a pre-regulated circuit is used to increase the power supply rejection ratio. The simulation results are at -30 °C∼130 °C. The output voltage of reference voltage is 947.5 μV, the temperature coefficient is 9.58 ppm/°C, and the power suppression ratio is -104.62 dB, which meets the design requirements of the power management chip.

A 3.95 ppm/°C 7.5 μW Second-Order Curvature Compensated Bandgap Reference in 0.11 μm CMOS

In order to meet the requirements of modern portable electronics for high accuracy and low power consumption of bandgap reference circuits, a new low-voltage bandgap reference with a second-order compensated circuit at 1.8 V is proposed. It features a new self-biased fully symmetric differential operational amplifier circuit with the help of split transistors for achieving low power consumption and high accuracy; by adding a new sub-threshold compensated circuit. The results of simulation show that the temperature coefficient of the second-order circuit is 3.95 ppm/°C in the temperature range of −40 to 125 °C, and the power consumption is only 7.5 μW; this meets both the requirements of high precision and low power consumption. At the same time, the output noise voltage of the design is less than 30 μV/sqrt (Hz) at a frequency of 100 Hz, and the low-frequency supply voltage rejection ratio is −103 dB@100 Hz; these are acceptable for bandgap reference circuits.

A 261mV Bandgap reference based on Beta Multiplier with 64ppm/0C temp coefficient

ABSTRACT In this paper, a low voltage bandgap reference circuit has been proposed. The introduction of a modified beta multiplier bias circuit decreased the mismatch caused by the PMOS transistors opamp contribution. By shifting the fixed resistors to the NMOSs drain side, the beta multiplier bias minimised threshold mismatch between the two NMOS transistors. A 200-point MC simulation showed a 0.9 mV standard deviation, with a 0.34% accuracy. The simulated temperature coefficient was 64 ppm/0C. The proposed circuit consumed 5.04 µW of power from a 0.45 V power supply voltage. A prototype was implemented in 65 nm CMOS technology occupying a 2888 µm2 silicon area, with the nominal value of the reference at 261 mV.

A Sub-1 V Temperature-Insensitive-PSR Bandgap Reference with Complementary Loop Locking

This paper presents a novel low-voltage bandgap reference with improved power supply rejection (PSR). The proposed circuit adopts a complementary loop locking approach for stabilizing the drain-source voltages of the current mirrors, which gives rise to a boost of the PSR performance by more than 30[Formula: see text]dB over [Formula: see text]–110∘C and at 1-V supply. An analysis shows that the PSR of the proposed bandgap reference is typically characterized with its insensitivity to temperature variations. The circuit is designed with a commercial 0.18-[Formula: see text]m CMOS process. The experiment results of Monte Carlo simulation demonstrate that the average PSR with 1-V supply is [Formula: see text][Formula: see text]dB at DC and is [Formula: see text][Formula: see text]dB at 1[Formula: see text]kHz (attained under a room temperature condition of 27∘C). And the temperature coefficient of the DC-based PSR is about 0.83%/∘C at 1-V supply, significantly decreased by three–six folds compared to other conventional designs. The quiescent current consumed is only about 13.5[Formula: see text][Formula: see text]A.

An improved fully integrated, high-speed, dual-modulus divider

A fully integrated 2n/2n+1 dual-modulus divider in GHz frequency range is presented. The improved structure can make all separated logic gates embed into correlative D flip—flops completely. In this way, the complex logic functions can be performed with a minimum number of devices and with maximum speed, so that lower power consumption and faster speed are obtained. In addition, the low-voltage bandgap reference needed by the frequency divider is specifically designed to provide a 1.0 V output. According to the design demand, the circuit is fabricated in 0.18 μm standard CMOS process, and the measured results show that its operating frequency range is 1.1–2.5 GHz. The dual-modulus divider dissipates 1.1 mA from a 1.8 V power supply. The temperature coefficient of the reference voltage circuit is 8.3 ppm/°C when the temperature varies from −40 to +125 °C. By comparison, the dual-modulus divide designed in this paper can possess better performance and flexibility.

Low-voltage bandgap reference with output-regulated current mirror in 90 nm CMOS

A low-voltage bandgap reference (BGR) circuit is designed and fabricated in a 90 nm CMOS technology. To mitigate error resulting from the mismatch in temperature dependency of the current in the output current mirror device and that of the BGR core, an output-regulated current mirror is incorporated. Experimental results show that the output voltage is 497.2 mV at 25°C with a temperature coefficient of 28.3 ppm/°C between −40°C and 80°C. The circuit occupies 0.0337 mm2 and dissipates 276.6 pW with a supply voltage of 1.2 V.

Erratum for ‘Low-voltage bandgap reference with output-regulated current mirror in 90 nm CMOS’

Erratum for ‘Low-voltage bandgap reference with output-regulated current mirror in 90 nm CMOS’

Low voltage bandgap reference with closed loop curvature compensation

A new low-voltage CMOS bandgap reference (BGR) that achieves high temperature stability is proposed. It feeds back the output voltage to the curvature compensation circuit that constitutes a closed loop circuit to cancel the logarithmic term of voltage VBE. Meanwhile a low voltage amplifier with the 0.5 μm low threshold technology is designed for the BGR. A high temperature stability BGR circuit is fabricated in the CSMC 0.5 μm CMOS technology. The measured result shows that the BGR can operate down to 1 V, while the temperature coefficient and line regulation are only 9 ppm/°C and 1.2 mV/V, respectively.

Low-power low-voltage reference using peaking current mirror circuit

A low-power low-voltage bandgap reference using the peaking current mirror circuit with MOSFETs operated in the subthreshold region is presented. A demonstrative chip was fabricated in 0.35 /spl mu/m CMOS technology, achieving the minimum supply voltage 1.4 V, the reference voltage around 580 mV, the temperature coefficient 62 ppm//spl deg/C, the supplied current 2.3 /spl mu/A, and the power supply noise rejection ratio of -84 dB at 1 kHz.

A 1.8-V ΔΣ modulator interface for an electret microphone with on-chip reference

The design of a delta-sigma ( ) analog-to-digital converter (ADC) for direct voltage readout of an electret micro- phone is presented. The ADC is integrated on the same chip with a bandgap voltage reference and is designed to be packaged to- gether with an electret microphone. Having a power consumption of 1.7 mW from a supply voltage of 1.8 V, the circuit is well suited for use in mobile applications. The single-loop, single-bit, fourth- order ADC operates at 64 times oversampling for a signal bandwidth of 11 kHz. The measured dynamic range is 80 dB and the peak signal-to-(noise distortion) ratio is 62 dB. The harmonic distortion is minimized by using an integrator with an instrumen- tation amplifier-like input which directly integrates the 125-mV peak single-ended voltage generated by the microphone. A com- bined continuous-time/switched-capacitor design is used to mini- mize power consumption. Index Terms—Analog-to-digital conversion, CMOS analog IC, continuous time, delta-sigma modulator, electret micro- phone, high input impedance, low-voltage bandgap reference, single-ended input, switched capacitor.

Design of low-voltage bandgap reference using transimpedance amplifier

The minimum supply voltage for implementing a typical bandgap reference is usually over 1.8 V. This minimum is mainly due to the limited input common-mode range of the opamp used in the bandgap reference. In this work, a low-voltage bandgap reference using a transimpedance amplifier that does not have this limitation is proposed and some of the design considerations for the proposed technique are briefly discussed. Based on this technique, a 1.2-V bandgap reference was implemented in a 1.2-/spl mu/m CMOS process (V/sub TN//spl ap/0.53 V and V/sub TP//spl ap/-0.91 V) with bipolar option. The variations of the output voltage over temperature (0/spl deg/C/spl les/T/spl les/100/spl deg/C) were measured to be less than /spl plusmn/1%.

A curvature-corrected low-voltage bandgap reference

A curvature-corrected bandgap reference that can function at supply voltages as low as 1 V, at a supply current of only 100 mu A, is presented. After trimming, this bandgap reference has a temperature coefficient (TC) of +or-4 p.p.m./ degrees C. The reference voltage is about 200 mV and it can easily be adjusted to higher values. The temperature range of this circuit is from 0 to 125 degrees C. This bandgap reference is realized using a standard bipolar process with base-diffused resistors.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>