"methods and apparatus to measure a transfer function of a control system"

A system comprising:

• a voltage signal source to output a voltage signal;
• a power supply to:
• receive a first signal from the power supply at a first point in a control loop at a digital signal processor;
• instruct the digital signal processor to add a reference signal having a predetermined frequency and a predetermined amplitude to the first signal to generate a combined signal in the digital signal processor;
• use the combined signal to generate a control signal for the power stage;
• sample the control signal at a second point around the control loop in the digital signal processor to generate a sampled signal;
• and
• a workstation to:
• receive a user input via a user interface;
• send instructions to the signal processor for controlling the operation of the signal processor;
• compare the sampled signal to the reference signal to determine a transfer function of the digital power supply;
• and
• display the transfer function on the user interface;
• a powered apparatus to receive a voltage rail from the power supply and to use the voltage rail to power the powered apparatus.

A machine-readable medium storing machine-readable instructions that, when executed, cause a machine to:

• receive a first signal from the power supply at a first point in a control loop at a digital signal processor;
• instruct the digital signal processor to add a reference signal having a predetermined frequency and a predetermined amplitude to the first signal to generate a combined signal in the digital signal processor;
• use the combined signal to generate a control signal for the power stage;
• sample the control signal at a second point around the control loop in the digital signal processor to generate a sampled signal;
• compare the sampled signal to the reference signal to determine a transfer function of the digital power supply;
• and
• display the transfer function on a user interface.