A Flexible 200kHz-20MHz Ring Oscillator in a 40nm CMOS Technology
By Murilo Pessatti,
Analog IPs are developed to meet a set of specific requirements, and to change its specifications for a different application, a significant amount of time and effort may have to be applied on customization and redesign. Companies designing analog and mixed-signal SoCs often resort to 3rd party IP companies to reduce time-tomarket, risk or due to lack of expertise in a specific domain. However, most of the times, there is no exact match in the market for an analog IP that would fit perfectly in the SoC. Hence, some level of customization must be carried out by the IP provider in order to fulfill their customer needs.
In this paper, we present a flexible ring oscillator IP designed for a 40nm CMOS technology, whose oscillation frequency can be chosen from 200kHz to 20MHz. It was developed using a new design approach, in which analog IPs are designed from scratch to be flexible, employing modular blocks that can be easily customized.
The IP is silicon proven. It works with a supply voltage of 1.2V and features 5% frequency accuracy, occupying an area of 0.0022mm2.
To provide this flexible solution, during the design phase, an exploration of the design space is carried out for the chosen circuit architecture, in this case a ring oscillator. Within the boundaries of the block capabilities, we analyze which parameters must be flexible to the user and assure that performance under process variations, power and area are met. Layout modularization is employed to make it easier to add/remove features. An HDL model is provided together with the IP datasheet once the user has chosen its parameters through a Web interface. This allows the system architect to quickly verify if the IP fits his/her needs, thereby speeding up the SoC development.
Murilo P. Pessatti is co-founder and CEO of Chipus Microelectronics since its inception back to 2008. Chipus is a Brazilian Analog and Mixed-signal Semiconductor Intellectual Property and Design Services company. He has 14 years of experience in Analog and Mixed-signal Integrated Circuit (IC) design and team management. Prior to found Chipus, He worked for CEITEC SA, Brazil, from 2006-2008, leading and managing a group of 13 analog IC designers working in the complete design and ramp-up of chips for a passive RFID products line.
He also worked for ChipIdea (acquired by Synopsys in 2009) from 2003-2006 as an analog IP designer in the power management group, developing power management unit IPs for top IDM companies, key blocks used inside smartphones, MP3 players and a plethora of portable devices with the function to manage the battery power of these devices efficiently. He has a MBA in project management for technology companies from PontifÃcia Universidade CatÃ³lica do Rio Grande do Sul (PUC-RS), Brazil, in 2009, a Master of Science in Electrical Engineer (MSEE) with emphasis in Microelectronics and Photonics from State University of Campinas (UNICAMP) Brazil, in 2002, and a degree in Electrical Engineer (BSEE), with emphasis in Electronics, from SÃ£o Paulo University (USP), Brazil, in 2000.