Mohammed Rachedine

US Patent:

7230505, Jun 12, 2007

Filed:

Apr 4, 2005

Appl. No.:

11/098110

Inventors:

Mohammed Rachedine - Mundelein IL, US
Daniel L. Kaczman - Gurnee IL, US

Assignee:

Freescale Semiconductor, Inc. - Austin TX

International Classification:

H03B 5/00
H03L 7/099

US Classification:

331179, 331 25, 331177 R, 331185

Abstract:

A VCO circuit including a VCO, a voltage supply and a control circuit. The VCO has a supply voltage input and a gain that changes with its supply voltage. The voltage supply has an adjust input and an output coupled to the supply voltage input of the VCO. The voltage supply adjusts the voltage level of its output in response to changes of the adjust input. The control circuit has a first adjust output coupled to the adjust input of the voltage supply to adjust the gain of the VCO. The VCO may include a frequency range adjust input controlled by the control circuit so that the gain of the VCO is adjusted when the frequency range is changed. For a multi-band VCO, the gain is adjusted for different frequency bands to maintain a relatively constant gain for each frequency band.