Regulators with offset voltage cancellation

A regulator comprising:

• an operational amplifier comprising a non-inverting input, an inverting input, and an output;
• a programmable offset voltage configured to cancel a built-in offset voltage of the regulator based on a code;
• a circuit configured to set the code based on a sensed built-in offset voltage of the regulator in response to an offset cancellation calibration mode enable signal;
• a first switch to connect the non-inverting input to the inverting input of the operational amplifier in response to the offset cancellation mode enable signal;
• and
• a second switch to disconnect the inverting input of the operational amplifier from a feedback path of the regulator in response to the offset cancellation calibration mode enable signal.

A regulator comprising:

• an operational amplifier comprising a non-inverting input, an inverting input, and a first output;
• a reference voltage node to provide a reference voltage to the non-inverting input of the operational amplifier;
• a regulated voltage node to supply a regulated voltage to a load based on the reference voltage;
• and
• a programmable offset voltage controlled to cancel a built-in offset voltage between the reference voltage and the regulated voltage.

A regulator comprising:

• an operational amplifier comprising a non-inverting input, an inverting input, and a first output;
• a reference voltage node to provide a reference voltage to the non-inverting input of the operational amplifier;
• a regulated voltage node to supply a regulated voltage to a load based on the reference voltage;
• a programmable offset voltage controlled to cancel a built-in offset voltage between the reference voltage and the regulated voltage;
• a first transistor electrically coupled to the first output of the operational amplifier and the regulated voltage node;
• a first current source electrically coupled to the regulated voltage node;
• a controller configured to connect the regulated voltage node to the inverting input of the operational amplifier during an operating mode of the regulator and to disconnect the regulated voltage node from the inverting input of the operating amplifier during an offset cancellation calibration mode of the regulator;
• an offset voltage sensing node;
• a second transistor electrically coupled to the first output of the operational amplifier and the offset voltage sensing node;
• and
• a second current source electrically coupled to the offset voltage sensing node,
• wherein the controller is configured to disconnect the non-inverting input from the inverting input of the operational amplifier during the operating mode of the regulator and to connect the non-inverting input to the inverting input of the operational amplifier during the offset cancellation calibration mode of the regulator.

A regulator comprising:

• an operational amplifier comprising a non-inverting input, an inverting input, and a first output;
• a reference voltage node to provide a reference voltage to the non-inverting input of the operational amplifier;
• a regulated voltage node to supply a regulated voltage to a load based on the reference voltage;
• a programmable offset voltage controlled to cancel a built-in offset voltage between the reference voltage and the regulated voltage;
• and
• an offset voltage sensing node;
• wherein the operational amplifier further comprises a second output, the first output electrically coupled to a first transistor to supply the regulated voltage on the regulated voltage node and the second output electrically coupled to a second transistor to supply a voltage on the offset voltage sensing node for sensing the built-in offset voltage between the reference voltage and the regulated voltage.

A method for offset voltage cancellation in a regulator, the method comprising:

• sensing a built-in offset voltage of a regulator during an offset cancellation calibration mode of the regulator;
• generating a code based on the sensed built-in offset voltage;
• and
• applying the code to a programmable offset voltage coupled between a non-inverting input and an inverting input of an operational amplifier of the regulator to cancel the built-in offset voltage of the regulator.

A method for offset voltage cancellation in a regulator, the method comprising:

• sensing a built-in offset voltage of a regulator during an offset cancellation calibration mode of the regulator;
• generating a code based on the sensed built-in offset voltage;
• and
• applying the code to a programmable offset voltage of the regulator to cancel the built-in offset voltage of the regulator,
• wherein sensing the built-in offset voltage comprises sensing whether an output voltage of the regulator during the offset cancellation calibration mode is above or below a target voltage, and
• wherein generating the code comprises incrementing a counter in response to the output voltage being below the target voltage and decrementing the counter in response to the output voltage being above the target voltage.

A method for offset voltage cancellation in a regulator, the method comprising:

• sensing a built-in offset voltage of a regulator during an offset cancellation calibration mode of the regulator;
• generating a code based on the sensed built-in offset voltage;
• and
• applying the code to a programmable offset voltage of the regulator to cancel the built-in offset voltage of the regulator,
• wherein sensing the built-in offset voltage comprises sensing whether an output voltage of the regulator during a first portion of the offset cancellation calibration mode is above or below a target voltage,
• wherein generating the code comprises incrementing a counter in response to the output voltage being below the target voltage and decrementing the counter in response to the output voltage being above the target voltage during the first portion of the offset cancellation calibration mode,
• wherein sensing the offset voltage further comprises sensing whether the output voltage of the regulator during a second portion of the offset cancellation calibration mode is above or below the target voltage, and
• wherein generating the code further comprises maintaining the counter in response to the output voltage being below the target voltage during the second portion of the offset cancellation calibration mode, decrementing the counter in response to both the output voltage being above the target voltage during the second portion of the offset cancellation calibration mode and below the target voltage during the first portion of the offset cancellation calibration mode, and maintaining the counter in response to both the output voltage being above the target voltage during the second portion of the offset cancellation calibration mode and the output voltage being above the target voltage during the first portion of the offset cancellation calibration mode.