A Novel CMOS Current Mode Bandgap Reference

A novel CMOS bandgap reference is presented. The output reference of this new current mode structure can be set to an arbitrary value above the bandgap voltage of silicon,avoiding offset in application. It also overcomes the systematic mismatch of conventional current mode bandgap references. The proposed bandgap reference has been implemented in UMC 0.18μm mixed mode technology. Under the supply voltage of 1.6V, the proposed bandgap reference provides an output reference of 1.45V and consumes 27μA of supply current. Using no curvature compensation,it can reach a temperature coefficient of 23ppm/℃ from 30 to 150℃ with a line regulation of 2. 1mV/V from 1.6 to 3V and a PSRR of 40dB at DC frequency. The chip area of the bandgap reference （without pad） is 0. 088mm^2.

A Near-1V 10ppm/℃ CMOS Bandgap Reference with Curvature Compensation

A low voltage bandgap reference with curvature compensation is presented. Using current mode structure, the proposed bandgap circuit has a minimum voltage of 900mV. Compensated through the VEB linearization technique, this bandgap reference can reach a temperature coefficient of 10ppmFC from 0 to 150℃. With a 1.1V supply voltage,the supply current is 43μA and the PSRR is 55dB at DC frequency. This bandgap reference has been verified in a UMC 0.18μm mixed mode CMOS technology and occupies 0. 186mm^2 of chip area.

A resistorless CMOS bandgap reference with below 1 V output

This paper proposes a resistorless CMOS bandgap reference (BGR) circuit capable of generating a voltage less than 1V and presents a high performance start up circuit that can make the BGR circuit achieve the correct operation point at power on. The simulation with Hspice was carried out using a 0 25 μm CMOS process. The results indicate that the proposed BGR circuit can operate on a 2 2 to 3 3 V power supply and its output voltage has a variation of 11 mV at -10 to 80 ℃.

Design of a Bandgap Reference with a Wide Supply Voltage Range

An on-chip voltage reference with a wide supply voltage range is required by some applications,especially that of power management （PM） controller chips applied to telecommunication, automotive, lighting equipment, etc., when high power supply voltage is needed. Accordingly,a new bandgap reference with a wide supply voltage range is proposed. Due to the improved structure,it features a high power supply rejection ratio （PSRR） and high temperature stability. In addition, an auxiliary micro-power reference is introduced to support the sleep mode of the PM chip and reduce its standby power consumption. The auxiliary reference provides bias currents in normal mode and a 1.28V reference voltage in sleep mode to replace the main reference and save power. Simulation results show that the reference provides a reference volt- age of 1.27V,which has a 3.5mV drift over the temperature range from -20 to 120~C and 56t^V deviation over a supply voltage range from 3 to 40V. The PSRR is higher than 100dB for frequency below 10kHz. The circuit was completed in 1.5tzm BCD （Bipolar-CMOS-DMOS） technology. The experimental results show that all main expectations are achieved.

Bandgap Reference Design by Means of Multiple Point Curvature Compensation

A new method,namely multiple point curvature compensation （MPCC）,is proposed for the design of a bandgap reference,and its design principles, theoretical derivation, and one feasible circuitry implementation are presented. Being different from traditional techniques, this idea focuses on finding multiple temperatures in the whole range at which the first order derivatives of the output reference voltage equal zero. In this way, the curve of the output reference voltage is flattened and a better effect of curvature compensation is achieved. The circuitry is simulated in ST Microelectronics 0. 18μm CMOS technology, and the simulated result shows that the average temperature coefficient is only 1ppm/℃ in the range from - 40 to 125℃.

A Piecewise-Linear Compensated Bandgap Reference

A bandgap voltage reference is presented with a piecewise linear compensating circuit in order to reduce the temperature coefficient.The basic principle is to divide the whole operating temperature range into some sub ranges.At different temperature sub ranges the bandgap reference can be compensated by different linear functions.Since the temperature sub range is much narrower than the whole range,the compensation error can be reduced significantly.Theoretically,the precision can be improved unlimitedly if the sub ranges are narrow enough.In the given example,with only three temperature sub ranges,the temperature coefficient of a conventional bandgap reference drops from 1 5×10 -5 /℃ to 2×10 -6 /℃ over the -40℃ to 120℃ temperature range.

Design of Bandgap Reference in Switching Power Supply

A bandgap voltage reference is designed to meet the requirements of low power loss,low temperature coefficient and high power source rejection ratio(PSRR) in the intergrated circuit. Based on the analysis of conventional bandgap reference circuit,and combined with the integral performance of IC,the specific design index of the bandgap reference is put forward. In the meantime,the circuit and the layout are designed with Chartered 0.35 μm dual gate CMOS process. The simulation result shows that the coefficient is less than 30ppm/℃ with the temperature from -50 ℃ to 150 ℃. The bandgap reference has the characteristics of low power and high PSRR.

Curvature Compensated CMOS Bandgap Reference with Novel Process Variation Calibration Technique

A lowtemperature coefficient（ TC） bandgap reference（ BGR） with novel process variation calibration technique is proposed in this paper. This proposed calibration technique compensating both TC and output value of BGR achieves fine adjustment step towards the reference voltage,while keeping optimal TC by utilizing large resistance to help layout match. The high-order curvature compensation realized by poly and p-diffusion resistors is introduced into the design to guarantee the temperature characteristic. Implemented in 180 nm technology,the proposed BGR has been simulated to have a power supply rejection ratio（ PSRR） of 91 dB@100 Hz. The calibration technique covers output voltage scope of 0. 49 V-0. 56 Vwith TC of 9. 45 × 10^（-6）/℃-9. 56 × 10^（-6）/℃ over the temperature range of-40 ℃-120 ℃. The designed BGR provides a reference voltage of 500 mV,with measured TC of 10. 1 × 10^（-6）/℃.

Trimmable bandgap reference circuit with exponential curvature compensation

This paper proposes an improved exponential curvature-compensated bandgap reference circuit to exploit the exponential relationship between the current gainβof the bipolar junction transistor(BJT)and the temperature as well as reduce the influence of resistance-temperature dependency.Considering the degraded circuit performance caused by the process deviation,the trimmable module of the temperature coefficient(TC)is introduced to improve the circuit stability.The circuit has the advantages of simple structure,high linear stability,high TC accuracy,and trimmable TC.It consumes an area of 0.09 mm^(2)when fabricated by using the 0.25-μm complementary metal-oxide-semiconductor(CMOS)process.The proposed circuit achieves the simulated power supply rejection(PSR)of about-78.7 dB@1 kHz,the measured TC of~4.7 ppm/℃over a wide temperature range from-55℃to 125℃with the 2.5-V single-supply voltage,and the tested line regulation of 0.10 mV/V.Such a high-performance bandgap reference circuit can be widely applied in high-precision and high-reliability electronic systems.

A Piecewise Curvature-Corrected CMOS Bandgap Reference with Negative Feedback

A piecewise curvature-corrected bandgap reference （BGR） with negative feedback is proposed. It features employing a temperature-dependent resistor ratio technique to get a piecewise corrected current, which corrects the nonlinear temperature dependence of the first-order BGR. The piecewise corrected current generator also forms negative feedback to improve the line regulation and power supply rejection （PSR）. Measurement results show the proposed BGR achieves a maximum temperature coefficient （TC） of 21.2ppm/℃ without trimming in the temperature range of - 50-125℃ and a PSR of - 60dB at 2.6V supply voltage. The line regulation is 0.8mV/V in the supply range of 2.6-5.6V. It is successfully implemented in an SMIC 0.35μm 5V n-well digital CMOS process with the effective chip area of 0.04mm^2 and power con- sumption of 0.18mW. The reference is applied in a 3,5V optical receiver trans-impedance amplifier.

A multiple transistor combination low-voltage curvature-corrected bandgap reference

A new bandgap reference（BGR） curvature compensation technology is proposed,which is a kind of multiple transistor combination.On the basis of the existing first-order bandgap reference technology,a compensation current circuit consisting of a sink current branch and a source current branch is added.The BGR was designed and simulated by using Semiconductor Manufacturing International Corporation（SMIC） 0.18μm CMOS process.The simulation results showed that when the power supply voltage was 1 V,the temperature coefficient of the BGR was 2.08 ppm/℃with the temperature range from—40 to 125℃,the power supply rejection ratio （PSRR） was—64.77 dB and the linear regulation was 0.44 mV/V with the supply power changing from 0.85 to 1.8 V.

Novel high PSRR high-order temperature-compensated subthreshold MOS bandgap reference

Novel high power supply rejection ratio （PSRR） high-order temperature-compensated subthreshold metal-oxidesemiconductor （MOS） bandgap reference （BGR） is proposed in Semiconductor Manufacturing International Corporation （SMIC） 0.13 gm complementary MOS （CMOS） process. By adopting subthreshold MOS field-effect transistors （MOSFETs） and the piecewise-curvature temperature-compensated technique, the output reference voltage＇s temperature performance of the subthreshold MOS BGR is effectively improved. The subthreshold MOS BGR achieves high PSRR performance by adopting the technique of pre-regulator. Simulation results show that the temperature coefficient （TC） of the subthreshold MOS BGR is 1.38× 10^-6/℃ when temperature is changed from -40 ℃ to 125 ℃ with a power supply voltage of 1.2 V. The subthreshold MOS BGR achieves the PSRR of - 104.54 dB, - 104.54 dB,- 104.5 dB, - 101.82 dB and - 79.92 dB at 10 Hz, 100 Hz, 1 kHz, 10 kHz and 100 kHz respectively.

A 0.19 ppm/°C bandgap reference circuit with high-PSRR

A high-order curvature-compensated CMOS bandgap reference（BGR） topology with a low temperature coefficient（TC） over a wide temperature range and a high power supply reject ratio（PSRR） is presented.High-order correction is realized by incorporating a nonlinear current INL, which is generated by ？V_（GS） across resistor into current generated by a conventional first-order current-mode BGR circuit. In order to achieve a high PSRR over a broad frequency range, a voltage pre-regulating technique is applied. The circuit was implemented in CSMC 0.5 μm 600 V BCD process. The experimental results indicate that the proposed topology achieves TC of0.19 ppm/°C over the temperature range of 165 °C（-40 to 125 °C）, PSRR of-123 d B @ DC and-56 d B @ 100 k Hz. In addition, it achieves a line regulation performance of 0.017%/V in the supply range of 2.8–20 V.

A novel precision curvature-compensated bandgap reference

A high precision high-order curvature-compensated bandgap reference compatible with the standard CMOS process, which uses a compensation proportional to VTlnT realized by utilizing voltage to current converters and the voltage current characteristics of a base-emitter junction, is presented. Experiment results of the proposed bandgap reference implemented with the CSMC 0.5μm CMOS process demonstrate that a temperature coefficient of 3.9 ppm/℃ is realized at 3.6 V power supply, a power supply rejection ratio of 72 dB is achieved, and the line regulation is better than 0.304 mV/V dissipating a maximum supply current of 42 μA.

Negative voltage bandgap reference with multilevel curvature compensation technique

A novel high-order curvature compensation negative voltage bandgap reference （NBGR） based on a novel multilevel compensation technique is introduced. Employing an exponential curvature compensation （ECC） term with many high order terms in itself, in a lower temperature range （TR） and a multilevel curvature compen- sation （MLCC） term in a higher TR, a flattened and better effect of curvature compensation over the TR of 165℃ （--40 to 125 ℃） is realised. The MLCC circuit adds two convex curves by using two sub-threshold operated NMOS. The proposed NBGR implemented in the Central Semiconductor Manufacturing Corporation （CSMC） 0.5 #m BCD technology demonstrates an accurate voltage of-1.183 V with a temperature coefficient （TC） as low as 2.45 ppm/℃over the TR of 165℃ at a -5.0 V power supply; the line regulation is 3 mV/V from a -5 to -2 V supply voltage. The active area of the presented NBGR is 370×180 μm2.

An offset-insensitive switched-capacitor bandgap reference with continuous output

An improved switched-capacitor bandgap reference with a continuous output voltage of 1.26 V has been implemented with Chartered 0.35-μm 5-V CMOS process. The output offset voltage, induced by non-ideal characteristics of operational amplifier and bias current generator, is suppressed by the proposed sample-and-hold circuit and self-bias technique. Experimental results show that the proposed circuit operates properly under a supply voltage varying from 3 to 5 V. The measured temperature coefficient is 112 ppm/℃ and the power supply rejection ratio of output voltage without any filtering capacitor is -40 dB and -33 dB at 100 Hz and 10 MHz, respectively.

A curvature calibrated bandgap reference with base-emitter current compensating in a 0.13μm CMOS process

In bandgap references,the effect caused by the input offset of the operational amplifier can be effectively reduced by the utilization of cascade bipolar junction transistors（BJTs）.But in modern CMOS logic processes,due to the small value ofβ,the base-emitter path of BJTs has a significant streaming effect on the collector current,which leads to a large temperature drift for the reference voltage.To solve this problem,a base-emitter current compensating technique is proposed in a cascade BJT bandgap reference structure to calibrate the curvature of the output voltage to temperature.Experimental results based on the 0.13μm logic CMOS process show that the reference voltage is 1.238 V and the temperature coefficient is 6.2 ppm/℃within the range of-40 to 125℃.

A low power bandgap reference with buffer working in the sub-threshold region for energy harvesting systems

We propose a bandgap reference, which works in sub-threshold regions to the reduce power consumption in applications such as those in energy harvesting systems that stimulate the development of power management for low power consumption applications.Measurements shows that the supply current of the proposed bandgap reference is only 6.87 μA, including a voltage buffer consuming 3.6 μA of supply current, when the supply voltage is 5 V.The supply voltage can vary from 3 to 11 V and the line regulation of the proposed bandgap reference output voltage is 0.875 mV/V at room temperature.The temperature coefficiency is 88.9 ppm from 10 to 100° C when the supply voltage is 5 V.

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 0.5μm 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/℃ and 1.2 mV/V, respectively.

A high precision high PSRR bandgap reference with thermal hysteresis protection

To meet the accuracy requirement for the bandgap voltage reference by the increasing data conversion precision of integrated circuits,a high-order curvature-compensated bandgap voltage reference is presented employing the characteristic of bipolar transistor current gain exponentially changing with temperature variations.In addition,an over-temperature protection circuit with a thermal hysteresis function to prevent thermal oscillation is proposed.Based on the CSMC 0.5μm 20 V BCD process,the designed circuit is implemented;the active die area is 0.17×0.20 mm;. Simulation and testing results show that the temperature coefficient is 13.7 ppm/K with temperature ranging from -40 to 150℃,the power supply rejection ratio is -98.2 dB,the line regulation is 0.3 mV/V,and the power consumption is only 0.38 mW.The proposed bandgap voltage reference has good characteristics such as small area,low power consumption, good temperature stability,high power supply rejection ratio,as well as low line regulation.This circuit can effectively prevent thermal oscillation and is suitable for on-chip voltage reference in high precision analog,digital and mixed systems.