Abstract: A voltage controlled oscillator circuit is disclosed. A CMOS circuit version is detailed. A relaxation oscillator has its input coupled by way of a voltage follower buffer to the input terminal where the control voltage is applied. The operating frequency is determined by the circuit resistor and capacitor values along with the control potential. A linear frequency versus voltage response is obtained and the circuit will operate at low supply voltages.

Abstract: A circuit is disclosed for operating an MOS transistor in its resistive mode. A cascode transistor is used to clamp the voltage across the resistive transistor to the required level. The circuit gain can be controlled by controlling voltage across the resistive transistor.

Abstract: A differential oscillator is supplied with a constant total current. A signal-controlled single-ended shunt circuit bypasses current around the oscillator thus varying the tail current oppositely. This in turn varies the signal delay in the oscillator transistors and hence oscillator frequency.

Abstract: A circuit for supplying a pair of currents that vary in opposite directions as a function of a control current. The pair of currents are coupled to an amplifying stage in which the gain varies in accordance with the relative magnitude of the currents. The circuit includes a differential current source having two output current terminals and a pair of controlled inputs. Both inputs are coupled to individual current sources. One input includes a resistor-diode current sink and the other input includes a current mirror sink. The control current is coupled to the current mirror thus varying the load on the related differential inputs. The current mirror input is also coupled to the diode current sink in the one differential input so that a delay can be introduced into the response to control current. That is, the control current must exceed a predetermined value before the gain reduction action occurs.

Abstract: A video amplifier, for use with a synchronous detector, employs a first differential amplifier stage, coupled through a level-shifting circuit to the synchronous detector output. A noise-responsive second differential amplifier stage has its output cross connected with the first differential amplifier and is biased to be normally unresponsive. In the event of an inverted noise impulse at the detector output, the second differential amplifier is turned on and its cross-connected output cancels the output of the first differential amplifier, thus canceling the noise impulse. If the noise is strong enough, the output will go into the black video region. This avoids the excess white video noise which results in very undesirable spot blooming.

Abstract: A low-Q mechanical resonator is operated in its series resonance mode in a circuit that includes an amplifier and voltage variable phase shifter. As the phase shift is varied, the resonator will shift its frequency to compensate the phase shift. The result is a voltage variable oscillator frequency. The low-Q resonator has a non-linear phase versus frequency characteristic so that frequency is not a linear function of control voltage. A plural emitter transistor is employed in one side of a non-linear differential control amplifier. The resulting non-linear transfer characteristic is used to compensate the non-linear oscillator characteristic so that the frequency versus control voltage is linear.

Abstract: Color television video signals are first converted into current analogs and then processed to provide the luminance and chrominance values required by the NISC or PAL standards. By using the current mode fewer critical parts are needed and the circuits are amendable to integrated circuit construction.

Abstract: In a color television receiver a pulse is generated corresponding to the horizontal beam deflection flyback interval. This pulse is coupled to a gating transistor and to an integrator. The integrator output is a sawtooth signal that is fed to a zero-crossing detector, the output of which is also coupled to the gating transistor. The gating transistor will then generate a pulse that corresponds to the second half of the flyback pulse and is therefore a nearly ideal source of color burst gate pulse.

Abstract: A low-Q mechanical resonator is operated in its series resonance mode in a circuit that includes an amplifier and voltage variable phase shifter. As the phase shift is varied, the resonator will shift its frequency to compensate the phase shift. The result is a voltage variable oscillator frequency. The low-Q resonator has a non-linear phase versus frequency characteristic so that frequency is not a linear function of control voltage. A plural emitter transistor is employed in one side of a differential control amplifier. The resulting non-linear transfer characteristic is used to compensate the non-linear oscillator characteristic so that the frequency versus control voltage is linear.

Abstract: A differential transistor pair has an antiresonant tank connected between collectors. Feedback is achieved using a pair of cross connected zener diodes biased into reverse breakdown. A balanced two-pin version provides paraphase output and an unbalanced single-pin version is available for single phase output. The single pin version can include a current mirror for biasing the zener diodes with constant current. The oscillator can be temperature compensated by means of a temperature programmed current source.

Abstract: A plurality of oscillator-modulator combinations is incorporated into a monolithic integrated circuit. A single pole multiple position switch is used to energize a single oscillator at a time, and a filter having a plurality of inputs and a common output is coupled to the modulator outputs. The modulators each have a common modulation input. Using this combination, a very simple switch can be used to control the modulated signal output at different carrier frequencies.

Abstract: In square wave signal processing, a plural signal combiner is provided with a reference input along with differential inputs for other signals to be combined. Each differential input terminal is provided with an emitter load by means of a plural emitter transistor connected to have a constant collector current. The combiner can process square wave signals to extract phase information.