A high-swing CMOS telescopic operational amplifier

Gulati, Kush; Lee, Hae-Seung

doi:10.1109/4.735542

Cited by 149 publications

(57 citation statements)

References 5 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The circuit on the right [214] uses an opamp to form the feedback loop. Another similar type of circuit is reported in [215].…”

Section: Current Sources and Mirrorsmentioning

confidence: 71%

See 1 more Smart Citation

Circuit Techniques for Low-Voltage and High-Speed A/D Converters

Waltari¹,

Halonen²

2003

The International Series in Engineering and Computer Science

View full text Add to dashboard Cite

The increasing digitalization in all spheres of electronics applications, from telecommunications systems to consumer electronics appliances, requires analog-to-digital converters (ADCs) with a higher sampling rate, higher resolution, and lower power consumption. The evolution of integrated circuit technologies partially helps in meeting these requirements by providing faster devices and allowing for the realization of more complex functions in a given silicon area, but simultaneously it brings new challenges, the most important of which is the decreasing supply voltage.Based on the switched capacitor (SC) technique, the pipelined architecture has most successfully exploited the features of CMOS technology in realizing high-speed high-resolution ADCs. An analysis of the effects of the supply voltage and technology scaling on SC circuits is carried out, and it shows that benefits can be expected at least for the next few technology generations. The operational amplifier is a central building block in SC circuits, and thus a comparison of the topologies and their low voltage capabilities is presented.It is well-known that the SC technique in its standard form is not suitable for very low supply voltages, mainly because of insufficient switch control voltage. Two low-voltage modifications are investigated: switch bootstrapping and the switched opamp (SO) technique. Improved circuit structures are proposed for both. Two ADC prototypes using the SO technique are presented, while bootstrapped switches are utilized in three other prototypes.An integral part of an ADC is the front-end sample-and-hold (S/H) circuit. At high signal frequencies its linearity is predominantly determined by the switches utilized. A review of S/H architectures is presented, and switch linearization by means of bootstrapping is studied and applied to two of the prototypes. Another important parameter is sampling clock jitter, which is analyzed and then minimized with carefully-designed clock generation and buffering.The throughput of ADCs can be increased by using parallelism. This is demonii strated on the circuit level with the double-sampling technique, which is applied to S/H circuits and a pipelined ADC. An analysis of nonidealities in double-sampling is presented. At the system level parallelism is utilized in a time-interleaved ADC. The mismatch of parallel signal paths produces errors, for the elimination of which a timing skew insensitive sampling circuit and a digital offset calibration are developed. A total of seven prototypes are presented: two double-sampled S/H circuits, a time-interleaved ADC, an IF-sampling self-calibrated pipelined ADC, a current steering DAC with a deglitcher, and two pipelined ADCs employing the SO technique.

show abstract

“…The circuit on the right [214] uses an opamp to form the feedback loop. Another similar type of circuit is reported in [215].…”

Section: Current Sources and Mirrorsmentioning

confidence: 71%

“…In the literature [214,215] the triode region current source has been employed as a tail current source in opamps. In principle it can be utilized in the output stage as well, but the local feedback loop has an effect on the opamp frequency response, requiring at least careful settling analysis and simulations.…”

Section: Current Sources and Mirrorsmentioning

confidence: 99%

Circuit Techniques for Low-Voltage and High-Speed A/D Converters

Waltari¹,

Halonen²

2003

The International Series in Engineering and Computer Science

View full text Add to dashboard Cite

show abstract

“…Designing of high performance analog circuits is challenging with reduced power supply voltages [1]. In an analog circuit design the main important circuit is an operational amplifier.…”

Section: Introductionmentioning

confidence: 99%

Design and Analysis of Low Power Pseudo Differential Class-Ab Telescopic Operational Amplifier

Shylu¹

2014

IJRET

View full text Add to dashboard Cite

show abstract

“…In an attempt to improve the signal swing while still maintaining a large dc gain. Gulati and Lee [18] proposed what they termed the High-Swing Telescopic Cascode. In their approach, they biased one of the current source transistors to operate in the triode region to reduce the minimum amount of voltage that must be allocated to that device.…”

Section: High Gain Amplifiersmentioning

confidence: 99%

“…The cascoding technique includes telescopic cascoding [18). folded cascoding [19] [20], and regulated cascoding [ 10][21], Cascoding topologies that exploit "stacking" of transistors were widely used in the past to achieve a high DC gain but they suffer from a limited output swing.…”

Section: High Gain Amplifiersmentioning

confidence: 99%

Strategies for enhancing DC gain and settling performance of amplifiers

Yan

View full text Add to dashboard Cite

A high-swing CMOS telescopic operational amplifier

Cited by 149 publications

References 5 publications

Circuit Techniques for Low-Voltage and High-Speed A/D Converters

Circuit Techniques for Low-Voltage and High-Speed A/D Converters

Design and Analysis of Low Power Pseudo Differential Class-Ab Telescopic Operational Amplifier

Strategies for enhancing DC gain and settling performance of amplifiers

Contact Info

Product

Resources

About