1. High Performance Operational Amplifier with 90dB Gain in SCL 180nm Technology
- Author
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Surya Padma, Sounak Das, Subhajit Sen, and Chetan D. Parikh
- Subjects
0209 industrial biotechnology ,Computer science ,020208 electrical & electronic engineering ,Frequency compensation ,Phase margin ,Differential amplifier ,02 engineering and technology ,Compensation (engineering) ,law.invention ,020901 industrial engineering & automation ,law ,Hardware_INTEGRATEDCIRCUITS ,0202 electrical engineering, electronic engineering, information engineering ,Electronic engineering ,Operational amplifier ,Cascode ,Electronic circuit ,DC bias - Abstract
This paper presents the design and implementation of a high-speed, high-gain fully differential opamp. The architecture consists of a telescopic cascode differential amplifier followed by a modified common-source second stage that includes an intermediate push-pull stage, individual CMFB circuits including frequency compensation for the first and second stages, RC Miller compensation for the main op-amp, and dc bias circuit blocks. The circuit is implemented in SCL 180nm technology, including layout and post-layout extracted characterization. It achieves a DC gain of 90dB with phase margin of 58° at 530MHz for a load of 1pF. Output voltage swing is +/-600mV for a +/-900mV supply. A sample-and-hold circuit built with the op-amp gives an accuracy of 60µV at 40MHz.
- Published
- 2020