Freescale Semiconductor,inc.

Motorola Corporation

Nihal J Godambe

Walt Kehler

Charles R Ruelke

John Wayne Simmons

Walter H Kehler

James C Goatley

A communication module includes a variable gain amplifier, a mixer stage responsive to the variable gain amplifier, a post-mixer amplifier stage responsive to the mixer stage, and an off-channel signal detector responsive to the post-mixer amplifier stage. The post-mixer amplifier stage is to produce a first differential signal and a second differential signal. The off-channel signal detector has a first input to receive the first differential signal and has a second input to receive the second differential signal. The off-channel signal detector includes a programmable hysteresis comparator module, and the off-channel signal detector has an output to produce an output signal that indicates whether an off-channel signal condition is detected.

Off-channel signal detector with programmable hysteresis

An apparatus and method are provided for tracking the poles of an integrated RC filter as well as the absolute value of a current source. A single tracking oscillator contains integrated elements such as a programmable resistor and fixed capacitor or a programmable capacitor and fixed resistor. The programmable element is programmed such that a particular response from the RC filter is achieved and the word used to program the programmable element is then supplied to other integrated RC filters having components that were fabricated at the same time as the RC filter in the tracking oscillator. A highly accurate external capacitor or resistor is supplied to determinate the absolute value of the programming element, which is used to program one or more current sources containing the programmable resistor.

Baseband RC filter pole and on-chip current tracking system

A system comprising a voltage controlled oscillator is disclosed. The voltage controlled oscillator includes a single input, a power input, and an oscillation input. The oscillation input is coupled to a amplitude detection device, which in turn provides an indication of an amplitude of the output of the VCO to a threshold detect module. Based upon the threshold detected at the threshold detect module, a threshold indicator is provided to a voltage supply module. The voltage supply powering the voltage controlled oscillator is varied, based upon a value of the threshold indicator.

Self-calibrating oscillator system

A level detector ( ) and corresponding method detects ( ) whether an output signal level of a VCO ( ) is within a window bounded by minimum and maximum thresholds. When the output signal level is not within the window, a loop-control element ( ) closes ( ) an AGC loop of the VCO and controls the gain of the VCO with a gain-control signal that tracks an AGC bias signal. When the output signal level is within the window, the loop-control element opens ( ) the AGC loop and controls the gain with a fixed bias signal derived from the AGC bias signal at the time the AGC loop is opened.

Method and apparatus for controlling a voltage controlled oscillator

A rectifier ( ) rectifies ( ) an output signal of a VCO ( ) to produce an envelope signal proportional to an amplitude of the output signal. An integrator ( ) integrates ( ) the envelope signal to produce a comparison signal, such that, in response to a change in the envelope signal, during a first mode of operation of the VCO, the comparison signal is allowed to change at a first rate, and, during a second mode of operation of the VCO, the comparison signal is allowed to change at a second rate different from the first rate. A comparator ( ) compares ( ) the comparison signal with a reference signal ( ) to produce a bias signal, and controls ( ) a gain of the VCO with the bias signal.

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Palatine, IL, United States of America

Nihal J Godambe