Electricity: power supply or regulation systems – Self-regulating – Using a three or more terminal semiconductive device as the...
Reexamination Certificate
2000-04-12
2001-04-03
Nguyen, Matthew (Department: 2838)
Electricity: power supply or regulation systems
Self-regulating
Using a three or more terminal semiconductive device as the...
C330S301000
Reexamination Certificate
active
06211658
ABSTRACT:
BACKGROUND OF THE INVENTION
Field of the Invention
The invention relates to a balanced voltage reference circuit that is integrated together with one or more amplifier circuits in a circuit module and is intended for operating point adjustment thereof. The balanced voltage reference circuit has a transistor operated as an emitter follower, to whose collector one pole of a direct-current source is connected and to whose base one end of a non-reactive resistor is connected. A further non-reactive resistor is connected on a first end to the collector of the transistor and to the other end of the non-reactive resistor. The further non-reactive resistor has a relatively low resistance and whose second end is connected to a signal point on an amplifier circuit, which signal point determines the operating point of the amplifier circuit.
The operating point of integrated amplifier circuits for signals is adjusted by voltage reference circuits, which are integrated on the same circuit module, in conjunction with operational amplifiers and balanced circuits. This increases the overall noise factor of the amplifier circuits, therefore, additional measures must be taken for noise suppression.
SUMMARY OF THE INVENTION
It is accordingly an object of the invention to provide a balanced voltage reference circuit, integrated with one or more amplifier circuits, for operating point adjustment, which overcomes the above-mentioned disadvantages of the prior art devices of this general type, which provides a capability for adjusting the operating point of low-noise amplifier circuits inside an integrated circuit module, without having to accept an additional housing pin for connection to external filter components.
With the foregoing and other objects in view there is provided, in accordance with the invention, an improved circuit module having a module body and an amplifier circuit with an operating point and a signal point disposed in the module body, the improvement containing:
a balanced voltage reference circuit disposed in the module body and including:
a direct current source;
a first non-reactive resistor having a first end and a second end;
a transistor operated as an emitter follower having a collector connected to the direct-current source and to the second end of the first non-reactive resistor, and a base connected to the first end of the first non-reactive resistor;
a second non-reactive resistor having a relatively low resistance in comparison with the first non-reactive resistor and formed of a first series resistor element having a first end and a second end and a second series resistor element having a first end and a second end, the first end of the first series resistor element connected to the second end of the first non-reactive resistor, the second end of the first series resistor element connected to the first end of the second series resistor element and defining a junction point, the second end of the second series resistor element connected to the signal point of the amplifier circuit and outputting a reference voltage for determining the operating point; and
a capacitance having a first end connected to the junction point and a second end to be connected to ground, the capacitance and the second non-reactive resistor defining an RC filter and the capacitance connected as a parallel element of the RC filter.
According to the invention, which relates to the balanced voltage reference circuit of the type mentioned initially, the object is achieved in that the further non-reactive resistor is split into two series resistor elements, and one end of the integrated capacitance is connected, as the parallel element of the RC filter, between the two resistor elements, and the other end of the capacitance is connected to ground.
The non-reactive resistor in the integrated circuit module can be split very easily. The solution according to the invention also requires only a very small layout area. It has been found that the minimum noise factor with a circuit topology analogous to the prior art is approximately the same, and the stability of the DC supply is improved. The other noise parameters R
n
(equivalent noise resistance) and G
opt
(impedance for the minimum noise factor) are not influenced, or are influenced only to a very minor extent, by the circuit according to the invention, so that low-noise power adaptation can be carried out in the same way as in the past.
Other features which are considered as characteristic for the invention are set forth in the appended claims.
Although the invention is illustrated and described herein as embodied in a balanced voltage reference circuit, integrated with one or more amplifier circuits, for operating point adjustment, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.
The construction and method of operation of the invention, however, together with additional objects and advantages thereof will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings.
REFERENCES:
patent: 4780690 (1988-10-01), Voorman
patent: 5736885 (1998-04-01), Wietecha et al.
patent: 5901088 (1999-05-01), Kraus
patent: 1 283 964 (1972-08-01), None
“Halbleiterschaltungstechnik”, Tietze/Schenk, 10thedition, 1993, pp. 62-64.
Beyer Stefan
Ganser Siegfried
Greenberg Laurence A.
Infineon - Technologies AG
Lerner Herbert L.
Nguyen Matthew
Stemer Werner H.
LandOfFree
Balanced voltage reference circuit, integrated with one or... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Balanced voltage reference circuit, integrated with one or..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Balanced voltage reference circuit, integrated with one or... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2449955