Miscellaneous active electrical nonlinear devices – circuits – and – Specific input to output function – Combining of plural signals
Patent
1998-02-27
1999-12-14
Lam, Tuan T.
Miscellaneous active electrical nonlinear devices, circuits, and
Specific input to output function
Combining of plural signals
327129, 327563, H03F 345
Patent
active
060022914
ABSTRACT:
A cubic-type function generator combines the outputs from three differential pairs of transistors to generate an output current that varies in a cubic-type manner in response to the input voltage. The input offset voltages of the three differential pairs are set to different values so that the center of the hyperbolic tangent function for each differential pair is shifted along the input axis. By combining the outputs from the three differential pairs out of phase, the separate tanh functions combine to form an output function having an S-shaped curve. The amplitude of the output curve can be adjusted by varying the absolute magnitude of the bias currents to the differential pairs. The tilt and output offset can be adjusted by varying the relative magnitude of the bias currents. By driving the differential pairs with a differential voltage signal that varies as a function of temperature, the present invention generates a cubic-type temperature function. The slope of the differential voltage signal can be adjusted so as to expand or compress the combined output function of the differential pairs along the input axis. The cubic-type function generator is particularly useful for providing temperature compensation for crystal oscillators because the parameters of the output function can be adjusted to precisely match the parameters of the crystal.
REFERENCES:
patent: 4460872 (1984-07-01), Mattisson
patent: 4475169 (1984-10-01), Gilbert
patent: 4476538 (1984-10-01), Gilbert
patent: 5648741 (1997-07-01), Wichern
patent: 5815039 (1998-09-01), Kimura
Analog Devices Inc.
Lam Tuan T.
LandOfFree
Cubic type temperature function generator with adjustable parame does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Cubic type temperature function generator with adjustable parame, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Cubic type temperature function generator with adjustable parame will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-867060