On Slew Rate Enhancement in Class-A Opamps Using Local Common-Mode Feedback
01 Jan 2015-pp 244-248
TL;DR: Analysis and simulation results show that using local common-mode feedback loops will lead to higher slew rate, because, when slewing, both upper and lower transistors receive signal dependent gate voltages with localCommon-Mode feedback, making the behavior similar to that of a class-AB output stage.
Abstract: The output common-mode voltage in multistage fully differential opamps can be set by using a single common-mode feedback loop around all stages or by independent loops for each stage. The two schemes are analyzed for their impact on the slew rate in a two-stage Miller-compensated class-A opamp. Analysis and simulation results show that using local common-mode feedback loops will lead to higher slew rate. This is because, when slewing, both upper and lower transistors receive signal dependent gate voltages with local common-mode feedback, making the behavior similar to that of a class-AB output stage. Also, with local common-mode feedback, the positive and negative slew rates are symmetric.
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01 Jan 2016
TL;DR: The design of analog cmos integrated circuits is universally compatible with any devices to read and is available in the book collection an online access to it is set as public so you can download it instantly.
Abstract: Thank you for downloading design of analog cmos integrated circuits. Maybe you have knowledge that, people have look hundreds times for their chosen books like this design of analog cmos integrated circuits, but end up in malicious downloads. Rather than enjoying a good book with a cup of coffee in the afternoon, instead they juggled with some harmful virus inside their computer. design of analog cmos integrated circuits is available in our book collection an online access to it is set as public so you can download it instantly. Our digital library spans in multiple countries, allowing you to get the most less latency time to download any of our books like this one. Kindly say, the design of analog cmos integrated circuits is universally compatible with any devices to read.
1,038 citations
TL;DR: In this article , a comparative study of one-stage-amp performance improvement based on simulations in 22 nm, 45 nm, 90 nm, and 180 nm in deep submicrometer CMOS technologies is discussed.
Abstract: A comparative study of one-stage-amp performance improvement based on simulations in 22 nm, 45 nm, 90 nm, and 180 nm in deep submicrometer CMOS technologies is discussed. Generic SPICE models were used to simulate the circuits. It is shown that in all cases a simple modification using resistive local common mode feedback increases open-loop gain and gain-bandwidth product, peak output currents, and slew rate by close to an order of magnitude. It is shown that this modification is especially appropriate for its utilization in current CMOS technologies since large factor improvements were not available in previous technologies. The OTAs with resistive local common mode feedback require simple phase lead compensation with a very small additional silicon area and keep supply requirements and static power dissipation unchanged.
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Book•
01 Jan 1999
TL;DR: The analysis and design techniques of CMOS integrated circuits that practicing engineers need to master to succeed can be found in this article, where the authors describe the thought process behind each circuit topology, but also consider the rationale behind each modification.
Abstract: The CMOS technology area has quickly grown, calling for a new text--and here it is, covering the analysis and design of CMOS integrated circuits that practicing engineers need to master to succeed. Filled with many examples and chapter-ending problems, the book not only describes the thought process behind each circuit topology, but also considers the rationale behind each modification. The analysis and design techniques focus on CMOS circuits but also apply to other IC technologies.
Table of contents
1 Introduction to Analog Design
2 Basic MOS Device Physics
3 Single-Stage Amplifiers
4 Differential Amplifiers
5 Passive and Active Current Mirrors
6 Frequency Response of Amplifiers
7 Noise
8 Feedback
9 Operational Amplifiers
10 Stability and Frequency Compensation
11 Bandgap References
12 Introduction to Switched-Capacitor Circuits
13 Nonlinearity and Mismatch
14 Oscillators
15 Phase-Locked Loops
16 Short-Channel Effects and Device Models
17 CMOS Processing Technology
18 Layout and Packaging
4,826 citations
Book•
01 Jan 1996
TL;DR: In this paper, the authors present an overview of current mirror and Opamp design and compensation for single-stage Amplifiers and Current Mirrors, as well as a comparison of the two types of Opamps.
Abstract: Partial table of contents: Integrated--Circuit Devices and Modelling. Processing and Layout. Basic Current Mirrors and Single--Stage Amplifiers. Noise Analysis and Modelling. Basic Opamp Design and Compensation. Advanced Current Mirrors and Opamps. Comparators. Switched--Capacitor Circuits. Nyquist--Rate D/A Converters. Oversampling Converters. Phase--Locked Loops. Index.
3,118 citations
"On Slew Rate Enhancement in Class-A..." refers background or result in this paper
...Assuming the second stage inputs (op1 and om1) to be virtual shorts to ground, the outputs op and om will respectively rise and fall at a rate Ic/Cc[1]....
[...]
...This is in contrast with single-ended opamps where the external feedback network provides the necessary DC negative feedback for stable operating point ([1], [2], and [3])....
[...]
01 Jan 2016
TL;DR: The design of analog cmos integrated circuits is universally compatible with any devices to read and is available in the book collection an online access to it is set as public so you can download it instantly.
Abstract: Thank you for downloading design of analog cmos integrated circuits. Maybe you have knowledge that, people have look hundreds times for their chosen books like this design of analog cmos integrated circuits, but end up in malicious downloads. Rather than enjoying a good book with a cup of coffee in the afternoon, instead they juggled with some harmful virus inside their computer. design of analog cmos integrated circuits is available in our book collection an online access to it is set as public so you can download it instantly. Our digital library spans in multiple countries, allowing you to get the most less latency time to download any of our books like this one. Kindly say, the design of analog cmos integrated circuits is universally compatible with any devices to read.
1,038 citations
"On Slew Rate Enhancement in Class-A..." refers result in this paper
...This is in contrast with single-ended opamps where the external feedback network provides the necessary DC negative feedback for stable operating point ([1], [2], and [3])....
[...]
TL;DR: An improved version of the SC-CMFB circuit is analyzed, which has very low errors due to charge injection and leakage currents and settles much faster than the traditional SC- CMFB circuit.
Abstract: A detailed analysis of the dc behavior of switched-capacitor common-mode feedback circuit (SC-CMFB) is presented. A mathematical model, useful for analysis, is developed and the expressions for the output common-mode (CM) voltage, with and without considering the charge injection of switches and leakage currents, are derived. Further, the expression for dc CM settling time, is presented. The effect of parasitic capacitances, dc CM gain, charge injection error, and leakage currents, on the steady-state value of the dc CM voltage is analyzed and design guidelines to minimize these errors are presented. Finally, an improved version of the SC-CMFB circuit is analyzed. This circuit has very low errors due to charge injection and leakage currents and settles much faster than the traditional SC-CMFB circuit.
169 citations
TL;DR: Design considerations are presented for attaining accurate output balancing in fully differential operational amplifiers over the useful operating frequency of the differential signals, and two circuit designs implemented in a 5-V, 1- mu m process are presented.
Abstract: Design considerations are presented for attaining accurate output balancing in fully differential operational amplifiers over the useful operating frequency of the differential signals. Such output balancing is obtained by merging the common-mode feedback and the differential gain paths as close to the front end of the amplifier as possible, ensuring maximum sharing of circuit components. Two circuit designs implemented in a 5-V, 1.75- mu m process are presented, one based on a two-stage topology and one based on a folded cascode topology. Experimental results for both designs are given. >
167 citations