Search International and National Patent Collections
Some content of this application is unavailable at the moment.
If this situation persists, please contact us atFeedback&Contact
1. (WO1998051014) DUAL BAND PHASE LOCKED LOOP USING INDEPENDENT CHARGE PUMPS
Latest bibliographic data on file with the International Bureau

Pub. No.: WO/1998/051014 International Application No.: PCT/US1998/008942
Publication Date: 12.11.1998 International Filing Date: 01.05.1998
IPC:
H03L 7/089 (2006.01) ,H03L 7/14 (2006.01) ,H03L 7/183 (2006.01)
H ELECTRICITY
03
BASIC ELECTRONIC CIRCUITRY
L
AUTOMATIC CONTROL, STARTING, SYNCHRONISATION, OR STABILISATION OF GENERATORS OF ELECTRONIC OSCILLATIONS OR PULSES
7
Automatic control of frequency or phase; Synchronisation
06
using a reference signal applied to a frequency- or phase-locked loop
08
Details of the phase-locked loop
085
concerning mainly the frequency- or phase-detection arrangement including the filtering or amplification of its output signal
089
the phase or frequency detector generating up-down pulses
H ELECTRICITY
03
BASIC ELECTRONIC CIRCUITRY
L
AUTOMATIC CONTROL, STARTING, SYNCHRONISATION, OR STABILISATION OF GENERATORS OF ELECTRONIC OSCILLATIONS OR PULSES
7
Automatic control of frequency or phase; Synchronisation
06
using a reference signal applied to a frequency- or phase-locked loop
08
Details of the phase-locked loop
14
for assuring constant frequency when supply or correction voltages fail
H ELECTRICITY
03
BASIC ELECTRONIC CIRCUITRY
L
AUTOMATIC CONTROL, STARTING, SYNCHRONISATION, OR STABILISATION OF GENERATORS OF ELECTRONIC OSCILLATIONS OR PULSES
7
Automatic control of frequency or phase; Synchronisation
06
using a reference signal applied to a frequency- or phase-locked loop
16
Indirect frequency synthesis, i.e. generating a desired one of a number of predetermined frequencies using a frequency- or phase-locked loop
18
using a frequency divider or counter in the loop
183
a time difference being used for locking the loop, the counter counting between fixed numbers or the frequency divider dividing by a fixed number
Applicants:
ANALOG DEVICES, INC. [US/US]; One Technology Way P.O. Box 9106 Norwood, MA 02062-9106, US
Inventors:
FAGUE, Daniel, E.; US
TEWKSBURY, Theodore, L.; US
Agent:
CONNORS, Matthew, E. ; Samuels, Gauthier, Stevens & Reppert Suite 3300 225 Franklin Street Boston, MA 02110, US
Priority Data:
09/019,25505.02.1998US
60/045,42502.05.1997US
Title (EN) DUAL BAND PHASE LOCKED LOOP USING INDEPENDENT CHARGE PUMPS
(FR) BOUCLE A PHASE ASSERVIE EN DOUBLE BANDE UTILISANT DES POMPES A CHARGE INDEPENDANTES
Abstract:
(EN) A dual band PLL circuit having a single VCO divider which is multiplexed between two VCOs by a switch at the VCO input. Two VCOs are used, one for each of the frequency bands. Two separate loop filters are utilized to drive each of the VCOs, and separate charge pumps that drive the loop filters. In this manner, complete isolation of the VCO is achieved. The charge pump which is active drives an optimized loop filter for that VCO charge pump output current. The charge pump that is inactive is placed in a high impedance mode, which preserves the charge of the loop filter in the inactive loop. This feature allows for quick re-acquisition when the inactive loop is re-activated. Also, the VCO gain constants need not have any special relationship. The loops for each of the VCOs can be designed independent of each other.
(FR) L'invention concerne un circuit à boucle à phase asservie en double bande ayant un seul diviseur par oscillateur commandé en tension, avec multiplexage entre deux oscillateurs commandés en tension via un interrupteur du côté entrée d'oscillateur. On utilise deux oscillateurs commandés en tension, à raison d'un par bande de fréquences. On utilise aussi deux filtres à boucle pour attaquer lesdits oscillateurs, et des pompes à charge indépendantes pour attaquer les filtres à boucle. Ainsi, l'isolation au niveau de l'oscillateur commandé en tension est totale. La pompe à charge qui est active attaque un filtre à boucle de type optimisé, pour le courant de sortie de pompe à charge d'oscillateur commandé en tension correspondant. La pompe à charge qui est inactive fonctionne en mode à haute impédance, ce qui préserve la charge du filtre à boucle dans la boucle inactive. La caractéristique en question permet une réacquisition rapide lorsque la boucle inactive est réactivée. Par ailleurs, il ne doit pas nécessairement exister de relation spéciale entre les constantes de gain d'oscillateur commandé en tension. Une conception indépendante est possible pour chacune des boucles correspondant aux deux oscillateurs considérés.
front page image
Designated States: European Patent Office (AT, BE, CH, CY, DE, DK, ES, FI, FR, GB, GR, IE, IT, LU, MC, NL, PT, SE)
Publication Language: English (EN)
Filing Language: English (EN)