Abstract: A circuit for driving output of a capacitive element between two voltage levels has at least one driver cell with a first switch pair connected in series between a first voltage source terminal and the capacitive element and a second switch pair connected in series between a second voltage source terminal and the capacitive element. One or more non-dissipative elements may be connected between a first common node of the first switch pair and a second common node of the second switch pair. Combinations of driver cell switches are activated and deactivated in sequences to provide step-wise transfer of energy to the capacitive element, subtracting from an input voltage, bypassing a driver cell, and adding to the input voltage. Switching stages to reach a high voltage output may be identical to but organized in reverse order from the switching stages to reach a low voltage output.

Abstract: A circuit for driving the voltage of a capacitive element between two voltage levels has at least one driver cell with a first pair of switches connected in series between a first terminal of a voltage source and the capacitive element, and a second pair of switches connected in series between a second terminal of the voltage source and the capacitive element. A plurality of non-dissipative elements may be connected in parallel or in series between the first pair of switches and the second pair of switches. Combinations of switches from the driver cells may be activated and deactivated in a defined sequence to provide step-wise transfer of energy to the capacitive element. The defined sequence may have a switching pattern with a voltage change portion arranged to cause a change in an output voltage of the capacitive element driver during application thereof on the capacitive element driver.

Abstract: A circuit for driving the voltage of a capacitive element between two voltage levels has at least one driver cell with a first pair of switches connected in series between a first terminal of a voltage source and the capacitive element, and a second pair of switches connected in series between a second terminal of the voltage source and the capacitive element. A plurality of non-dissipative elements may be connected in parallel or in series between the first pair of switches and the second pair of switches. Combinations of switches from the driver cells may be activated and deactivated in a defined sequence to provide step-wise transfer of energy to the capacitive element. The defined sequence may have a switching pattern with a voltage change portion arranged to cause a change in an output voltage of the capacitive element driver during application thereof on the capacitive element driver.

Abstract: A circuit for driving the voltage of a capacitive element between two voltage levels has at least one driver cell with a first pair of switches connected in series between a first terminal of a voltage source and the capacitive element, and a second pair of switches connected in series between a second terminal of the voltage source and the capacitive element. One or more non-dissipative elements may be connected between the common node of the first pair of switches and the common node of the second pair of switches. Combinations of switches from the driver cells may be activated and deactivated in a defined sequence to provide step-wise transfer of energy to the capacitive element. In one sequence, switches in a selected driver cell may subtract a specified voltage from an input voltage, bypass the selected driver cell, and add the specified voltage to the input voltage.

Abstract: Certain aspects of the present disclosure generally relate a regulator. For example, the regulator may include a control stage, a sense capacitor having first and second terminals, the first terminal coupled to an output of the voltage regulator, and a current amplifier having an input coupled to the second terminal of the sense capacitor and an output coupled to the control stage. The control stage of the regulator may adjust the output voltage of the regulator based at least in part on a current generated by the current amplifier.

Abstract: A circuit for driving the voltage of a capacitive element between two voltage levels has at least one driver cell with a first pair of switches connected in series between a first terminal of a voltage source and the capacitive element, and a second pair of switches connected in series between a second terminal of the voltage source and the capacitive element. One or more non-dissipative elements may be connected between the common node of the first pair of switches and the common node of the second pair of switches. Combinations of switches from the driver cells may be activated and deactivated in a defined sequence to provide step-wise transfer of energy to the capacitive element. In one sequence, switches in a selected driver cell may subtract a specified voltage from an input voltage, bypass the selected driver cell, and add the specified voltage to the input voltage.

Abstract: Certain aspects of the present disclosure provide methods and apparatus for generating an envelope tracking power supply voltage. For example, certain aspects of the present disclosure provide an envelope tracking power supply having a linear amplifier having an output coupled to a power supply node of an amplifier, wherein a power supply node of the linear amplifier is coupled to a first voltage supply node. The envelope tracking power supply may also include a switch mode power supply having an output coupled to the power supply node of the amplifier. Certain aspects also include a circuit having a first switch coupled to the first voltage supply node and a second switch coupled to a second voltage supply node, wherein a power supply node of the switch mode power supply is coupled to the first switch and the second switch.

Abstract: Certain aspects of the present disclosure provide methods and apparatus for level shifting an input signal ranging between certain voltage levels to generate an output signal ranging between other voltage levels with low power, high speed, and immunity to noise. One example level-shifting circuit generally includes a node for receiving an input signal ranging between a first voltage level and a second voltage level, a first circuit path coupled to the node and configured to level shift the input signal to generate an output signal ranging between a third voltage level and a fourth voltage level, a pulse generator coupled to the node and configured to generate a pulse based on a transition in the input signal between the first and second voltage levels, and a second circuit path connected in parallel with the first path and configured to temporarily short the first path based on the generated pulse.

Abstract: Certain aspects of the present disclosure provide methods and apparatus for generating an envelope tracking power supply voltage. For example, certain aspects of the present disclosure provide an envelope tracking power supply having a linear amplifier having an output coupled to a power supply node of an amplifier, wherein a power supply node of the linear amplifier is coupled to a first voltage supply node. The envelope tracking power supply may also include a switch mode power supply having an output coupled to the power supply node of the amplifier. Certain aspects also include a circuit having a first switch coupled to the first voltage supply node and a second switch coupled to a second voltage supply node, wherein a power supply node of the switch mode power supply is coupled to the first switch and the second switch.

Abstract: Certain aspects of the present disclosure provide methods and apparatus for generating an envelope tracking power supply voltage. For example, certain aspects of the present disclosure provide an envelope tracking power supply having a linear amplifier having an output coupled to a power supply node of an amplifier, wherein a power supply node of the linear amplifier is coupled to a first voltage supply node. The envelope tracking power supply may also include a switch mode power supply having an output coupled to the power supply node of the amplifier. Certain aspects also include a circuit having a first switch coupled to the first voltage supply node and a second switch coupled to a second voltage supply node, wherein a power supply node of the switch mode power supply is coupled to the first switch and the second switch.

Abstract: Certain aspects of the present disclosure generally relate a regulator. For example, the regulator may include a control stage, a sense capacitor having first and second terminals, the first terminal coupled to an output of the voltage regulator, and a current amplifier having an input coupled to the second terminal of the sense capacitor and an output coupled to the control stage. The control stage of the regulator may adjust the output voltage of the regulator based at least in part on a current generated by the current amplifier.

Abstract: An integrated circuit is disclosed for current-controlled voltage regulation. In an example aspect, the integrated circuit includes a voltage regulator and a current-controlled clamp. The voltage regulator has a regulator output node and produces a regulator current. The voltage regulator includes an error amplifier and an output transistor. The error amplifier has first and second input nodes and an error amplifier output node, with the first input node coupled to a reference voltage. The error amplifier generates an error amplifier output voltage at the output node. The output transistor is coupled between the error amplifier output node and the regulator output node. The output transistor is coupled to the second input node via the regulator output node to establish a feedback path for the voltage regulator. The current-controlled clamp is coupled to the error amplifier output node and clamps the error amplifier output voltage based on the regulator current.

Abstract: An integrated circuit is disclosed for current-controlled voltage regulation. In an example aspect, the integrated circuit includes a voltage regulator and a current-controlled clamp. The voltage regulator has a regulator output node and produces a regulator current. The voltage regulator includes an error amplifier and an output transistor. The error amplifier has first and second input nodes and an error amplifier output node, with the first input node coupled to a reference voltage. The error amplifier generates an error amplifier output voltage at the output node. The output transistor is coupled between the error amplifier output node and the regulator output node. The output transistor is coupled to the second input node via the regulator output node to establish a feedback path for the voltage regulator. The current-controlled clamp is coupled to the error amplifier output node and clamps the error amplifier output voltage based on the regulator current.

Abstract: A voltage regulator control implementation dynamically detects and sets specified headroom for a low dropout (LDO) regulator at different loads to enable the LDO regulator to maintain high performance in conjunction with improved power efficiency. In one instance, an upstream voltage regulator may adaptively adjust an output voltage supplied to an input supply rail of a downstream LDO regulator based on an indication from the LDO regulator. The adaptively adjusted input voltage enables the downstream LDO regulator to achieve high performance and improved power efficiency across the entire range of load conditions.

Abstract: Certain aspects of the present disclosure generally relate a dual feedback loop regulator. For example, the regulator may include a first amplifier having an output coupled to an output node of the regulator, the output node further coupled to a first feedback path and a second feedback path of the regulator. A first input of a second amplifier may be coupled to the first feedback path and a second input of the second amplifier may be coupled to a reference path. The regulator may also include a transconductance stage having a first transistor and a first current source, the first transistor and the current source coupled to the first feedback path and the second feedback path, and a transimpedance stage coupled to the transconductance stage and an input of the first amplifier.

Abstract: Certain aspects of the present disclosure generally relate a dual feedback loop regulator. For example, the regulator may include a first amplifier having an output coupled to an output node of the regulator, the output node further coupled to a first feedback path and a second feedback path of the regulator. A first input of a second amplifier may be coupled to the first feedback path and a second input of the second amplifier may be coupled to a reference path. The regulator may also include a transconductance stage having a first transistor and a first current source, the first transistor and the current source coupled to the first feedback path and the second feedback path, and a transimpedance stage coupled to the transconductance stage and an input of the first amplifier.

Abstract: A voltage regulator control implementation dynamically detects and sets specified headroom for a low dropout (LDO) regulator at different loads to enable the LDO regulator to maintain high performance in conjunction with improved power efficiency. In one instance, an upstream voltage regulator may adaptively adjust an output voltage supplied to an input supply rail of a downstream LDO regulator based on an indication from the LDO regulator. The adaptively adjusted input voltage enables the downstream LDO regulator to achieve high performance and improved power efficiency across the entire range of load conditions.

Abstract: Certain aspects of the present disclosure provide methods and apparatus for generating an envelope tracking power supply voltage. For example, certain aspects of the present disclosure provide an envelope tracking power supply having a linear amplifier having an output coupled to a power supply node of an amplifier, wherein a power supply node of the linear amplifier is coupled to a first voltage supply node. The envelope tracking power supply may also include a switch mode power supply having an output coupled to the power supply node of the amplifier. Certain aspects also include a circuit having a first switch coupled to the first voltage supply node and a second switch coupled to a second voltage supply node, wherein a power supply node of the switch mode power supply is coupled to the first switch and the second switch.

Abstract: Certain aspects of the present disclosure provide methods and apparatus for level shifting an input signal ranging between certain voltage levels to generate an output signal ranging between other voltage levels with low power, high speed, and immunity to noise. One example level-shifting circuit generally includes a node for receiving an input signal ranging between a first voltage level and a second voltage level, a first circuit path coupled to the node and configured to level shift the input signal to generate an output signal ranging between a third voltage level and a fourth voltage level, a pulse generator coupled to the node and configured to generate a pulse based on a transition in the input signal between the first and second voltage levels, and a second circuit path connected in parallel with the first path and configured to temporarily short the first path based on the generated pulse.

Abstract: A voltage regulator control implementation dynamically detects and sets specified headroom for a low dropout (LDO) regulator at different loads to enable the LDO regulator to maintain high performance in conjunction with improved power efficiency. In one instance, an upstream voltage regulator may adaptively adjust an output voltage supplied to an input supply rail of a downstream LDO regulator based on an indication from the LDO regulator. The adaptively adjusted input voltage enables the downstream LDO regulator to achieve high performance and improved power efficiency across the entire range of load conditions.