System and method for video transmission line fault detection

A circuit for determining faults at an output of a signal processing circuit, comprising:

• a short detection circuit, coupled to the output of the signal processing circuit, the short detection circuit receives an output signal from the output of the signal processing circuit and generates a first signal indicative of whether there is a short present at said output of said signal processing circuit;
• a load detection circuit, coupled to the output of the signal processing circuit, the load detection circuit receives the output signal from the output of the signal processing circuit and generates a second signal indicative of whether there is a load coupled to said output of said signal processing circuit;
• an input signal detect circuit, coupled an input of the signal processing circuit, the input signal detect circuit receives an input signal from the input of the signal processing circuit and generates a third signal indicative of whether there is a signal present at the input of the signal processing circuit;
• wherein said short detection circuit is adapted to use said third signal to enable the output of said first signal;
• wherein said load detection circuit is adapted to use said third signal to enable the output of said second signal;
• and
• wherein the short detection circuit, the load detection circuit and the input signal detect circuit are distinct from each other.

A circuit for determining whether a short is present at an output of a signal processing circuit, comprising:

• a signal detection circuit, coupled to the output of the signal processing circuit, the short detection circuit receives an output signal from the output of the signal processing circuit and generates a first signal indicative of whether an amplitude of a sampled output signal related to an output signal of said signal processing circuit is below a threshold;
• an input signal detect circuit, coupled to an input of the signal processing circuit, the input signal detect circuit receives an input signal from at the input of the signal processing circuit and generates a third signal indicative of whether there is a signal present at the input of the signal processing circuit;
• wherein said signal detection circuit is adapted to use said third signal to enable the output of said first signal;
• and
• wherein the signal processing circuit, the signal detection circuit and the input signal detect circuit are distinct from each other.

A method of monitoring an output of a video amplifier, comprising:

• detecting a first signal indicative of a short condition at said output of said video amplifier;
• detecting a second signal indicative of a load condition at said output of said video amplifier;
• and
• wherein the steps of detecting the first signal and detecting the second signal are performed by circuits that are distinct from each other.