Amplifiers – With semiconductor amplifying device – Including class d amplifier
Reexamination Certificate
2007-10-30
2009-08-11
Choe, Henry K (Department: 2817)
Amplifiers
With semiconductor amplifying device
Including class d amplifier
C330S20700P
Reexamination Certificate
active
07573330
ABSTRACT:
A digital power amplifier (or power switching amplifier or power switch) for use in a digital transmitter includes a low impedance multi-stage driver circuit having a low impedance pre-driver and a low impedance driver. The drive circuit drives a power switch stage having two power transistors configured in a current mode class-D push-pull configuration. Utilization of gallium nitride (GaN) transistors or pseudomorphic high electronic mobility transistors (pHEMT) (or combination thereof) and sizing the transistors progressively larger in the driver than in the pre-driver (at least about 3×) provides a reduction in output impedance of the driver circuit and progressive increases in the power driving capability of the succeeding stage. This allows the use of a power amplifier at higher frequencies without altering or affecting the power efficiency and allows use of a digital power amplifier for a digital transmitter.
REFERENCES:
patent: 5023566 (1991-06-01), El-Hamamsy et al.
patent: 5903188 (1999-05-01), Swanson et al.
patent: 7116168 (2006-10-01), Makino et al.
patent: 7312654 (2007-12-01), Roeckner et al.
patent: 7456685 (2008-11-01), Chen
patent: 2005/0134372 (2005-06-01), Atmur
patent: 2006/0006950 (2006-01-01), Burns et al.
International Search Report issued by the European Patent Office on Jun. 20, 2008 in International Application No. PCT/US2007/023022.
Written Opinion of the International Searching Authority issued by the European Patent Office on Jun. 20, 2008 in International Application No. PCT/US2007/023022.
Bergsma Adrian
Ilowski John
Outaleb Noureddine
Choe Henry K
McCutcheon Robert D.
Nortel Networks Limited
LandOfFree
High efficiency digital power amplifier does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with High efficiency digital power amplifier, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and High efficiency digital power amplifier will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-4065274