Full range voltage-controlled ring oscillator in 0.18 [mu]m CMOS for low-voltage operation

• Published in: Electronics letters Vol. 46; no. 1; p. 1
• Main Authors: Tiao, Y-S, Sheu, M-L
• Format: Journal Article
• Language: English
• Published: Stevenage John Wiley & Sons, Inc 06.01.2010
• ISSN: 0013-5194; 1350-911X

A new differential delay cell with a complementary current control to increase the control voltage range as well as the operation frequency is proposed for low-voltage operation. The new differential delay cell is employed in a four-stage voltage-controlled ring oscillator (VCRO). The VCRO is implemented, using 0.18 μm 1P6M CMOS process and 1.8 V supply voltage. Measured results show that, a wide operation frequency range from 5.36 to 3.03 GHz is achieved for the full range control voltage from 0 to 1.8 V. Measured phase noise is 2107 dBc/Hz at 1 MHz offset from the 5.22 GHz centre frequency.