Digital logic voltage regulators and related methods generate a regulated voltage via controlled switching of a power transistor. A digital logic voltage regulator includes a voltage level comparator, a power transistor, and a charge accumulator. The voltage level comparator generates a digital control signal that alternates between a first voltage level and a second voltage level in response to changes in relative voltage level between the regulated output voltage and the target voltage. The digital control signal causes the power transistor to switch from off to on in response to a reduction of the regulated output voltage relative to the target voltage and causes the power transistor to switch from on to off in response to an increase of the regulated output voltage relative to the target voltage. The charge accumulator decreases variation in the regulated output voltage that would occur without the charge accumulator.

Disclosed is a bandgap reference circuit, which includes a first current generator that generates a first current proportional to a temperature, a second current generator that outputs a second current obtained by mirroring the first current to a first node at which a reference voltage is formed, a first resistor that is connected with the first node and is supplied with the second current, and a first bipolar junction transistor (BJT) that includes an emitter node connected with the first resistor, a base node supplied with a first power, and a collector node supplied with a second power different from the first power.

Circuits and methods that provide for fast power up and power down times in a multi-stage LDO regulator. In one embodiment, a multi-stage LDO regulator circuit includes, for each stage for which fast power up and/or power down times are desired, at least one transconductance amplifier coupled and configured to compare a primary reference voltage to one of a secondary reference voltage for the stage or an output voltage of the stage, and coupling and configuring the at least one transconductance amplifier to charge and/or discharge an associated capacitor to achieve a desired charge level within a specified time independently of the value of the associated capacitor. In general, the transconductance amplifiers of each stage are configured to charge and/or discharge an associated capacitor in synchronism with a voltage present on the primary reference voltage input.

A supply-glitch-tolerant voltage regulator includes a regulated voltage node and an output transistor having a source terminal, a gate terminal, and a drain terminal. The source terminal is coupled to the regulated voltage node. The supply-glitch-tolerant voltage regulator includes a first current generator coupled between a first node and a first power supply node. The supply-glitch-tolerant voltage regulator includes a second current generator coupled between the first node and a second power supply node. The supply-glitch-tolerant voltage regulator includes a feedback circuit coupled to the first current generator and the second current generator and is configured to adjust a voltage on the first node based on a reference voltage and a voltage level on the regulated voltage node. The supply-glitch-tolerant voltage regulator includes a diode coupled between the drain terminal and the first power supply node and a resistor coupled between the gate terminal and the first node.

A voltage regulator, including an amplifier, a voltage setting circuit and a power transistor, is provided. The amplifier includes a first current source and a second current source. The amplifier has two input terminals to respectively receive a reference voltage and a feedback voltage. The first current source is coupled between the operating power source and an output terminal of the amplifier, and provides a first current to the output terminal. The second current source is coupled between the output terminal and a reference ground terminal, and draws a second current from the output terminal. The voltage setting circuit is coupled to the output terminal, and increases a driving voltage on the output terminal according to the first current in a voltage bypass mode. The power transistor receives the driving voltage and generates an output voltage according to the driving voltage based on the operating power source.

According to one embodiment, a constant voltage circuit includes: a first gain stage configured to output a first voltage amplified based on an output voltage and a reference voltage; a first transistor configured to control the output voltage based on the first voltage applied to a gate; and a second circuit configured to control a first signal based on a second voltage obtained by delaying an output timing of the output voltage and a third voltage that is based on the output voltage. In a case of the first signal being at a first logic level, a first current flows through the first gain stage, and in a case of the first signal being at a second logic level, a second current flows through the first gain stage.

An aspect relates to an apparatus, including: a ring oscillator coupled between a first node and a first voltage rail; a control circuit coupled to the first node; a delay line coupled between a second node and the first voltage rail; and a voltage regulator including an input coupled to the first node and an output coupled to the second node.

The present disclosure relates to a low-dropout regulator that limits a quiescent current. It mainly includes an error amplifier, an output switching transistor, a feedback switching transistor, a current duplicating circuit, and a clamping current source. The clamping current source is added between an input voltage and the feedback switching transistor, so that a feedback current outputted by the feedback switching transistor is clamped, and the highest value is only proportional to a current value of the clamping current source. In this way, the quiescent current outputted by the low-dropout regulator is no longer increasing indefinitely in proportional to a load current, which can effectively solve the technical problems of poor stability and decreased efficiency caused by the infinite increase of the quiescent current.

Systems and circuits include an amplifier having an output; a switching circuit coupled to the output of the amplifier to provide a bias current to bias the amplifier; first current generating circuitry coupled to the switching circuit; and second current generating circuitry coupled to the output of the amplifier and to the switching circuit. In operation, the switching circuit provides the bias current, during a first time period, in response to a first signal generated by the first current generating circuitry, and provides the bias current, during a second time period, after the first time period, in response to a second signal generated by the second current generating circuitry.

In examples, an apparatus includes a FET, first and second voltage-to-current circuits, a current selection circuit, and a comparator. The FET has first and second segments. The first segment has a first gate coupled to the first voltage-to-current circuit, a first source, and a first drain. The second segment has a second gate coupled to the second voltage-to-current circuit, a second source coupled to the first source, and a second drain coupled to the first drain. The current selection circuit has a current selection circuit output and first and second current selection inputs. The first current selection circuit input is coupled to the first voltage-to-current circuit. The second current selection circuit input is coupled to the second voltage-to-current circuit. The comparator has a comparator output and first and second comparator inputs, the first comparator input is coupled to the current selection circuit output.