Electricity: power supply or regulation systems – Output level responsive – Using a three or more terminal semiconductive device as the...
Reexamination Certificate
1998-06-29
2001-01-16
Wong, Peter S. (Department: 2838)
Electricity: power supply or regulation systems
Output level responsive
Using a three or more terminal semiconductive device as the...
C323S280000, C323S314000
Reexamination Certificate
active
06175224
ABSTRACT:
FIELD OF THE INVENTION
The present invention generally relates to electronic circuits, and, more particularly, to a voltage regulator, and to a method therefor.
BACKGROUND OF THE INVENTION
In electronic circuits, voltage regulators provide substantially constant supply voltages for voltage sensitive portions of the circuit. Usually, regulators have a pass transistor to change a preferably low voltage drop between input and output, a voltage sensor at the output and a feedback unit which controls the pass transistor. The output voltage (e.g., constant 5 volts) should be independent of temperature, so that a temperature compensation circuit is sometimes required.
U.S. Pat. No. 5,686,821 to Brokaw [1] teaches a regulator with a two-resistor voltage sensor carrying a current proportional to the absolute temperature (PTAT). The resistors (R9 and R10 in
FIG. 4
of [1]) have a value ratio related to a voltage provided by a bandgap reference. Positive and negative temperature coefficients of the current and the bandgap voltage compensate each other. A further useful reference is: Horowitz, P., Hill, W.: “The art of electronics”, Second Edition, Cambridge University Press, chapter 6.15: “Bandgap (V
BE
) reference”, on pages 335-341 [2].
The output voltage should also have low noise components. Also, the feedback unit should not cause the regulator to oscillate. Regulators can have so-called bypass capacitors which function as noise filters and pole suppression filters. But, the bypass capacitor increases the turn-on time of the regulator. Capacitors are also not wanted because of their physical size.
The present invention seeks to provide regulators which mitigate or avoid these and other disadvantages and limitations of the prior art.
REFERENCES:
patent: 4064448 (1977-12-01), Eatock
patent: 4636710 (1987-01-01), Stanojevic
patent: 4902959 (1990-02-01), Brokaw
patent: 5394078 (1995-02-01), Brokaw
patent: 5406222 (1995-04-01), Brokaw
patent: 5625278 (1997-04-01), Thiel et al.
patent: 5631551 (1997-05-01), Scaccianoce et al.
patent: 5631598 (1997-05-01), Miranda et al.
patent: 5686821 (1997-11-01), Brokaw
Laxton Gary L.
Motorola Inc.
Parker Lanny L.
Wong Peter S.
LandOfFree
Regulator circuit having a bandgap generator coupled to a... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Regulator circuit having a bandgap generator coupled to a..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Regulator circuit having a bandgap generator coupled to a... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2501330