Time standard circuit with delay line oscillator

A circuit comprising;

• a comparing means having first and second inputs and an output;
• an oscillator means including an inverter coupled to a delay line and variable delay element, the inverter and the variable delay element cooperating to hold the frequency of the oscillator means constant, coupled to the first input of the comparing means;
• and
• a delay inverter circuit comprising a variable delay element coupled to a respective inverter;
• the delay inverter circuit being coupled in common with the oscillator means and being further coupled to the second input of the comparing means;
• the comparing means sensing the phase difference between the output signal of the delay inverter circuit and an output signal of the oscillator means and providing an error signal wherein said delay inverter circuit comprises a series of inverters and variable delay elements.

An integrated circuit comprising;

• an oscillator means having an input, an output, a delay line and a variable delay element, said delay line and said variable delay element co-acting to hold the output signal frequency of said oscillator means substantially constant;
• a comparator having first and second inputs and an output;
• said input, of said oscillator means, being coupled to the first input of said comparator;
• a series of variable delay inverter circuits, said series of variable delay inverter circuits having an input and an output;
• the input of said series of variable delay inverter circuits being coupled to the input of the oscillator means;
• each of said variable delay inverter circuits in said series including a respective variable delay;
• the output of said series of variable delay inverter circuits being coupled to the second input of the comparator;
• said comparator circuit sensing the phase difference between the output signal of the series of variable delay inverter circuits and the input signal of the oscillator circuit and providing an error signal, at its output, proportional to said phase difference;
• and
• a feedback loop coupled to each variable delay inverter circuit in said series of variable delay inverter circuits and to the variable delay element in said oscillator to correct for said sensed phase difference and establish a uniform and stable time standard at said oscillator output.

An integrated circuit comprising;

• an oscillator having an input, an output, an inverter, and a distributed inductance and capacitance transmission line and a variable delay element which vary together to hold the frequency of oscillation substantially constant;
• said output, of said oscillator, being coupled to the first input of a comparator circuit having two inputs and an output;
• a series of inverter means, each of which is coupled to a respective variable delay, coupled in parallel to the input of the oscillator and to a second input of said comparator circuit;
• said comparator circuit sensing the difference between the output signal of the inverter series and the output signal of the oscillator and providing an error signal, at its output, proportional to said difference;
• and
• a feedback loop coupled to the variable delay element in both said oscillator and in said inverter series to correct for said sensed difference to establish a uniform and stable time standard at said oscillator output.