Circuits and methods for regulator diagnostics

Apparatus comprising:

• a voltage regulator comprising:
• an amplifier having a first input coupled to receive a reference voltage, a second input coupled to receive a feedback signal and an output configured to provide a node voltage;
• and
• a current mirror coupled to the output of the amplifier and coupled to the second input of the amplifier, wherein the current mirror receives the node voltage from the amplifier and provides the feedback signal to the amplifier, wherein the current mirror is supplied by a supply voltage;
• and
• a diagnostic circuit having a first input coupled to receive the reference voltage, a second input coupled to receive the node voltage and an output at which is provided a voltage regulator diagnostic signal indicative of whether or not the voltage regulator can maintain voltage regulation.

Apparatus comprising:

• a current regulator comprising:
• an amplifier having a first input coupled to receive a reference voltage, a second input coupled to receive a feedback signal and an output configured to provide a gate voltage;
• and
• a current mirror coupled to the output of the amplifier and coupled to the second input of the amplifier, wherein the current mirror receives the gate voltage from the amplifier and provides the feedback signal to the amplifier, wherein a current mirrored by the current mirror is established by a current source;
• and
• a diagnostic circuit having a first input coupled to receive the reference voltage, a second input coupled to receive the gate voltage and an output configured to provide a current regulator diagnostic signal indicative of whether or not the current regulator can maintain current regulation.

Apparatus comprising:

• a regulator configured to generate a regulated output comprising:
• means for generating a difference signal having a first input coupled to receive a reference voltage, a second input coupled to receive a feedback signal associated with the regulated output, and an output at which a control voltage is provided;
• means, responsive to the control voltage, for generating the regulated output;
• and
• means for comparing voltages to provide a diagnostic signal indicative of whether or not the regulator is able to maintain regulation of the regulated output, wherein the voltage comparing means is configured to compare the control voltage to a reference voltage.