Abstract: An improved coarse frequency detector includes a first storage device responsive to a data signal and a sub-multiple of a clock signal for detecting a first transition in the data signal during a predetermined state of the sub-multiple of the clock signal and generating an intermediate signal, and a second storage device responsive to the data signal and the intermediate signal for detecting a second transition in the data signal having the same polarity as the first transition during the predetermined state of the sub-multiple of the clock signal and generating an up-pulse.

Abstract: A rotational frequency detector system including a rotational frequency detector responsive to a data signal and a clock signal. The rotational frequency detector is configured to compare the frequency of the clock signal to the frequency of the data signal to define frequency up and frequency down signals that adjust the frequency of the clock signal to be equal to the frequency of the data signal. A step control system is responsive to the rotational frequency detector and a step clock signal and is configured to define predetermined pulse widths for the frequency up and frequency down signals.

Abstract: A harmonic detector including a pattern detector circuit responsive to a clock signal and a data signal configured to detect a target bit pattern from said data signal, and a time-out circuit responsive to said pattern detector circuit configured to detect the absence of said target bit pattern during a predetermined time-out parameter for indicating when said clock signal exceeds said data signal by a factor of two or more.

Abstract: A frequency acquisition system for a tunable oscillator is provided that generally includes a frequency-locked loop circuit including a detector system, responsive to the frequency of an output signal of a tunable oscillator and the frequency of a reference signal, to provide a digital output signal representative of a difference in frequency between the output signal and the reference signal, a register circuit for storing a value representative of the present control state of the tunable oscillator; and an accumulator circuit responsive to a value representative of the present control state of the tunable oscillator and to the digital output signal for providing an updated value for adjusting the frequency of the tunable oscillator towards the frequency of the reference signal.

Abstract: A frequency acquisition system for a tunable oscillator is provided that generally includes a frequency-locked loop circuit including a detector system, responsive to the frequency of an output signal of a tunable oscillator and the frequency of a reference signal, to provide a digital output signal representative of a difference in frequency between the output signal and the reference signal, a register circuit for storing a value representative of the present control state of the tunable oscillator; and an accumulator circuit responsive to a value representative of the present control state of the tunable oscillator and to the digital output signal for providing an updated value for adjusting the frequency of the tunable oscillator towards the frequency of the reference signal.

Abstract: A circuit for varying the temperature of a first bipolar transistor in order to thermally compensate for self-heating effects of an associated device in a common signal path with the first transistor, the first transistor being configured within an isolated collector region. The circuit includes a second bipolar transistor provided within the isolated collector region and thermally coupled to the first transistor, the second transistor operable for providing heat to the first transistor to alter the temperature to a predetermined level, thus changing the operational voltage characteristics of the first transistor so as to minimize shifts in offset voltage.