Communication semiconductor integrated circuit device and...

Telecommunications – Receiver or analog modulated signal frequency converter – Local control of receiver operation

Reexamination Certificate

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

C455S084000, C455S260000, C455S126000, C455S180300, C455S190100, C455S264000, C331S025000, C331S016000, C375S327000, C375S344000

Reexamination Certificate

active

11519061

ABSTRACT:
The invention provides a communication semiconductor integrated circuit device (RF IC) capable of pulling in the frequency of a PLL circuit to a desired set frequency at high speed even in the case where a frequency settable range of the PLL circuit is wide without providing a current source other than a current source for charging and discharging in an normal operation. An oscillator as a component of a PLL circuit is constructed so as to be operative in a plurality of bands. In a state where a control voltage of the oscillator is fixed to a predetermined value, an oscillation frequency of the oscillator is measured in each of bands and stored in a storing circuit. A set value for designating a band supplied at the time of PLL operation is compared with the stored measured frequency value. From a result of comparison, a band to be actually used in the oscillator is determined, and a frequency difference between the maximum frequency of the selected band and the set frequency is obtained. Further, a control voltage closest to the set frequency is determined on the basis of the frequency difference and the frequency variable range of the selected band and the control voltage is applied to the oscillator to start oscillating operation. After that, a PLL loop is closed and locked.

REFERENCES:
patent: 5203023 (1993-04-01), Saito et al.
patent: 5608354 (1997-03-01), Hori
patent: 5727019 (1998-03-01), Tatsumi
patent: 5734970 (1998-03-01), Saito
patent: 5819161 (1998-10-01), Saito
patent: 5835530 (1998-11-01), Hawkes
patent: 6188258 (2001-02-01), Nakatani
patent: 6195400 (2001-02-01), Maeda
patent: 6678512 (2004-01-01), Kaminski et al.
patent: 6738646 (2004-05-01), Miyoshi et al.
patent: 7072392 (2006-07-01), Xia et al.
patent: PCT/GB02/05152 (2002-04-01), None

LandOfFree

Say what you really think

Search LandOfFree.com for the USA inventors and patents. Rate them and share your experience with other people.

Rating

Communication semiconductor integrated circuit device and... does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Communication semiconductor integrated circuit device and..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Communication semiconductor integrated circuit device and... will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFUS-PAI-O-3741767

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.