Amplifiers – With semiconductor amplifying device – Including atomic particle or radiant energy impinging on a...
Reexamination Certificate
2003-04-30
2004-08-24
Choe, Henry (Department: 2817)
Amplifiers
With semiconductor amplifying device
Including atomic particle or radiant energy impinging on a...
C250S2140AG
Reexamination Certificate
active
06781468
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Technical Field of the Invention
The present invention relates generally to high-frequency photo-amplifier circuits, and more particularly to power supply rejection of high-frequency photo-amplifier circuits.
2. Description of Related Art
The ability of a circuit to disregard noise on the supply line is referred to as the power supply rejection of the circuit. High frequency circuits have traditionally had poor power supply rejection due to the high bandwidth handled by the circuits. For example, in high frequency photo-amplifier circuits with large bandwidths in the gigabit/s range, it has become increasingly difficult to filter noise on the supply line.
In addition, with the increase in the number of components placed on a circuit board, there has been a corresponding increase in the amount of broadband noise observed on the supply line. If the level of noise is significant enough, the integrity of any signal produced by the photo-amplifier circuit may be degraded.
Conventional mechanisms for improving the power supply rejection in photo-amplifier circuits have included complex and elaborate filters and/or differential amplifier circuits, used for common mode rejection of noise signals. However, as bandwidths increase and the number of components per board increase, there is a need for improved power supply rejection in photo-amplifier circuits.
SUMMARY OF THE INVENTION
Embodiments in accordance with the invention provide a symmetrical photo-amplifier circuit with improved power supply rejection. Typically, the photo-amplifier circuit includes a signal circuit and a reference circuit, in which the inductances and parasitic capacitances from mechanical sources, such as bond wires and substrates, are matched between the signal circuit and the reference circuit. The signal circuit and reference circuit are typically coupled to a filly differential preamplifier circuit for common mode rejection of noise signals on the power supply line. The signal circuit typically receives an optical signal on the power supply line and is coupled to an input of a first amplifier. The reference circuit is typically electrically similar to the signal circuit and receives a noise signal substantially identical to the noise signal received at the signal circuit. The reference circuit is further coupled to an input of a second amplifier. Signals output from the first and second amplifiers are input to a differential amplifier for common mode rejection of the noise signals.
REFERENCES:
patent: 4575629 (1986-03-01), Schnell et al.
patent: 5521555 (1996-05-01), Tazartes et al.
patent: 5589682 (1996-12-01), Brown et al.
patent: 5691663 (1997-11-01), Nayebi et al.
patent: 5945878 (1999-08-01), Westwick et al.
patent: 5955918 (1999-09-01), Uno
patent: 6259322 (2001-07-01), Muza
patent: 6323734 (2001-11-01), Henrion et al.
patent: 6329878 (2001-12-01), Edwards et al.
patent: 6597245 (2003-07-01), Yamazaki
patent: 60-157307 (1985-08-01), None
patent: 3-165609 (1989-11-01), None
Kirk Giboney et al.;Next-Generation Parallel-Optical Data Links,IEEE 2001; pp. 859-860.
I. A. Buckman et al.;Parallel Optical Interconnects;Thursday Afternoon, CLEO 2000; pp. 535-536.
Kirk Giboney et al.;The PONI Optoelectronic Platform;IEEE 1999; pp. 25-26.
Paul Rosenberg et al.;The PONI-I Parallel-Optical Link;IEEE 1999; pp. 763-769.
Kirk S. Giboney et al.;The Ideal Light Source for Datanets;IEEE Spectrum; Feb. 1998; pp. 43-53.
A. Yuen et al.;Parallel Optical Interconnections Development at HP Labs;IEEE 1997; pp. 191-192.
Al Yuen et al.;Parallel Optical Links for Gigabyte/s Data Communication;IEEE 1997; pp. 193-196.
Kenneth H. Hahn et al.;Gigabyte/s Data Communications with the POLO Parallel Optical Link;IEEE 1996; pp. 301-307.
Flower Graham M.
Giboney Kirk S.
Robinson Michael A.
LandOfFree
Photo-amplifier circuit with improved power supply rejection does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Photo-amplifier circuit with improved power supply rejection, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Photo-amplifier circuit with improved power supply rejection will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3362642