Electronic circuit, power supply circuit, method of measuring circuit characteristics

A power supply circuit, comprising:

• a reference voltage generator circuit configured to output a constant voltage;
• an amplifier configured to generate a power supply voltage in response to the constant voltage;
• a feedback circuit configured to supply a negative feedback signal to an input of the amplifier;
• AD converters configured to perform AD conversion with respect to a first analog signal, a second analog signal, and a third analog signal to output a first digital signal, a second digital signal, and a third digital signal, respectively;
• and
• an arithmetic unit configured to adjust characteristics of the feedback circuit in response to the outputs of the AD converters,
• wherein the arithmetic unit includes:
• a first phase adjustor configured to adjust a phase of the first digital signal through the Hilbert transform to produce an output;
• a second phase adjustor configured to adjust a phase of the second digital signal through the Hilbert transform to produce an output;
• a third phase adjustor configured to adjust a phase of the third digital signal through the Hilbert transform to produce an output;
• a first mixer circuit configured to multiply the output of the first phase adjustor and the output of the second phase adjustor;
• and
• a second mixer circuit configured to multiply the output of the first phase adjustor and the output of the third phase adjustor,
• wherein adjustment is variably made to characteristics of the feedback circuit in response to an output of the first mixer circuit and an output of the second mixer circuit.

An integrated circuit, comprising:

• a reference voltage generator circuit configured to output a constant voltage;
• an amplifier configured to generate a power supply voltage in response to the constant voltage;
• a feedback circuit configured to supply a negative feedback signal to an input of the amplifier;
• AD converters configured to perform AD conversion with respect to a first analog signal, a second analog signal, and a third analog signal to output a first digital signal, a second digital signal, and a third digital signal, respectively;
• and
• an arithmetic unit configured to adjust characteristics of the feedback circuit in response to the outputs of the AD converters,
• wherein the arithmetic unit includes:
• a first phase adjustor configured to adjust a phase of the first digital signal through the Hilbert transform to produce an output;
• a second phase adjustor configured to adjust a phase of the second digital signal through the Hilbert transform to produce an output;
• a third phase adjustor configured to adjust a phase of the third digital signal through the Hilbert transform to produce an output;
• a first mixer circuit configured to multiply the output of the first phase adjustor and the output of the second phase adjustor;
• a second mixer circuit configured to multiply the output of the first phase adjustor and the output of the third phase adjustor;
• and
• a core circuit configured to operate with a drive voltage that is the power supply voltage,
• wherein adjustment is variably made to characteristics of the feedback circuit in response to an output of the first mixer circuit and an output of the second mixer circuit.

A method of measuring characteristics of a circuit, comprising:

• applying an analog input signal responsive to an analog oscillating signal having a desired frequency to a circuit to cause the circuit to output an analog output signal;
• performing AD conversion with respect to the analog oscillating signal, the analog input signal, and the analog output signal to generate a digital oscillating signal, a digital input signal, and a digital output signal;
• adjusting a phase of the digital oscillating signal through the Hilbert transform;
• adjusting a phase of the digital input signal through the Hilbert transform;
• adjusting a phase of the digital output signal through the Hilbert transform;
• multiplying the phase-adjusted digital oscillating signal and the phase-adjusted digital input signal to generate a first multiplication result;
• multiplying the phase-adjusted digital oscillating signal and the phase-adjusted digital output signal to generate a second multiplication result;
• obtaining a ratio between an amplitude of the analog input signal and an amplitude of the analog output signal in response to the first multiplication result and the second multiplication result;
• and
• obtaining a difference between a phase of the analog input signal and a phase of the analog output signal in response to the first multiplication result and the second multiplication result.

A non-transitory recording medium having a program stored therein for calculating amplitude and phase characteristics, the program causing an arithmetic apparatus to perform:

• adjusting a phase of a first digital signal through the Hilbert transform;
• adjusting a phase of a second digital signal through the Hilbert transform;
• adjusting a phase of a third digital signal through the Hilbert transform;
• multiplying the phase-adjusted first digital signal and the phase-adjusted second digital signal to generate a first multiplication result;
• multiplying the phase-adjusted first digital signal and the phase-adjusted third digital signal to generate a second multiplication result;
• obtaining a ratio between an amplitude of the second digital signal and an amplitude of the third digital signal in response to the first multiplication result and the second multiplication result;
• and
• obtaining a difference between a phase of the second digital signal and a phase of the third digital signal in response to the first multiplication result and the second multiplication result,
• wherein the first digital signal is a digital oscillating signal obtained by AD-converting an analog oscillating signal having a desired frequency, and the second digital signal is a digital input signal obtained by AD-converting an analog input signal responsive to the analog oscillating signal, the analog input signal being input into a circuit, the third digital signal being a digital output signal obtained by AD-converting an analog output signal output by the circuit in response to the analog input signal.