Abstract: Circuits and methods for paralleling voltage regulators are provided. Improved current sharing and regulation characteristics are obtained by coupling control terminals of the voltage regulators together which results in precise output voltages and proportional current production. Distributing current generation among multiple paralleled voltage regulators improves heat dissipation and thereby reduces the likelihood that the current produced by the voltage regulators will be temperature limited.

Abstract: A power supply unit is adapted to automatically switch its operational mode between a light load mode and a heavy load mode depending on the level of its output current. The unit has a first error amplification circuit for controlling a first output circuit in the heavy load mode, and a second error amplification circuit for controlling the second output circuit in the light load mode. The first and the second output circuits are controllably enabled and disabled in the opposite manner based on the level of the output current. Thus, the unit can operate on a reduced consumption current with an improved transient response when operating in the light load mode.

Abstract: An LDO with over-current protection includes a first and a second P-type transistor, a sensing resistor, a comparator, and an error amplifier. The channel aspect ratio of the first P-type transistor is much higher than that of the second P-type transistor. The first P-type transistor generates output voltage source according to input voltage source and current control signal. The sensing resistor is coupled among the input voltage source, the second P-type transistor, and the comparator, providing a sensing voltage. The comparator generates a current limiting signal according to first reference voltage and the sensing voltage. When the current limiting signal enables the error amplifier, the error amplifier adjusts voltage of the current control signal according to second reference voltage and voltage divided from the output voltage source; when the current limiting signal disables the error amplifier, voltage of the current control signal is not adjusted.

Abstract: A voltage regulation circuit intended to generate a regulated voltage for an electronic device, comprising: a transconductance amplifier based on a pair of MOS type differential amplifiers, said amplifier having a first input onto which a reference potential is applied and a second input onto which a counter reaction of said regulated voltage is input; a follower stage connected to the output from said transconductance amplifier; a MOS type transistor that will be used to make the output stage of the regulation circuit with a source connected to a first power supply potential. The transconductance amplifier comprises a resistive load 360 with a profile in K/gm, where gm is the transconductance coefficient of said input differential pair, said resistive load being connected to said first power supply potential.

Abstract: A low drop-out voltage regulator with high-performance linear and load regulation, comprising: a reference voltage circuit, capable of providing a reference voltage; a differential amplifier; a power device, capable of driving a load resistor; a feedback circuit, disposed between the differential amplifier and the power device so that the differential amplifier outputs a correction voltage after the reference voltage and a feedback voltage across the feedback circuit; and a voltage buffer for frequency compensation, disposed between the differential amplifier and the power device, the voltage buffer comprising a complementary type buffer.

Abstract: A low dropout voltage regulator is described having a pass device, differential amplifiers, and a feedback loop including a low pass filter. Two differential amplifiers arranged in parallel coupled to the low pass filter in the feedback loop provide a specified and stable DC voltage whose input-to-output voltage difference is low. Improved stability, reduced die area, improved power supply rejection ratio, increased bandwidth, decreased power consumption, and better electrostatic discharge (ESD) protection may result.

Abstract: A reference voltage regulation circuit (143) is provided in which one or more input voltage signals (Vref, Vref?) are selectively coupled to a configurable amplifier (114) which is coupled through a sample and hold circuit (120) to a voltage follower circuit (122) which is coupled in feedback to the configurable amplifier (114) for generating an adjusted output voltage at a circuit output (130), where the voltage follow circuit comprises a resistor divider circuit (126) that is controlled by a calibration signal (Cal<n:0>) generated by a counter circuit (128) selectively coupled to the output of the configurable amplifier when configured as a comparator for generating the calibration signal in response to a clock signal, where the calibration signal represents a voltage error component (Verror, Voffset) that is removed from the circuit output when the calibration signal is applied to the resistor divider circuit during normal operational.

Abstract: A control circuit for a polarity inverting buck-boost DC-DC converter, includes an operational trans-conductance amplifier that has inputs to which a sensed voltage difference signal is applied and an output connected to an input of a voltage-to-duty-cycle converter. A compensation capacitance is connected between the output of the amplifier and a fixed supply terminal. The compensation capacitance includes a first capacitor that is permanently connected between the output of the amplifier and the fixed supply terminal and a second capacitor that has a switched connection between the output of the amplifier and the fixed supply terminal. The first capacitor has a small capacitance compared to the second capacitor. The switched connection of the second capacitor is controlled by a continuous-discontinuous mode detection circuit.

Abstract: The present invention provides a low dropout (LDO) regulator with a stability compensation circuit. A “zero frequency” tracking as well as “non-dominant parasitic poles' frequency reshaping” are performed to achieve a good phase margin for the LDO by means of the compensation circuit. In this compensation method neither a large load capacitor nor its equivalent series resistance is needed to stabilize a regulator. LDO regulators, in system on chip application, having load capacitors in the range of few nano-Farads to few hundreds of nano-Farads can be efficiently compensated with this compensation method. A dominant pole for the regulator is realized at an internal node and the second pole at an output node of the regulator is tracked with a variable capacitor generated zero over a range of load current to cancel the effect of each other. A third pole of the system is pushed out above the unity gain frequency of the open loop transfer function with the help of the frequency compensation circuit.

Abstract: A voltage regulator with a local feedback loop is disclosed, which provides adaptive control currents responsive to load transient to regulate abrupt voltage variations. The voltage regulator has an amplifier having a first input coupled to a reference voltage, a second input coupled to a feedback signal, and an output producing a first control signal; an output transistor having a control input, a first electrode coupled to a supplied voltage, and a second electrode coupled to an output terminal to output a regulated output voltage; a feedback circuit coupled to the output terminal to produce the feedback signal; and an adaptive biasing device coupled to the output terminal and the control input of the output transistor, for outputting control currents responsive to variations in the regulated output voltage to drive the output transistor to compensate the variations.

Abstract: A voltage regulator includes an undervoltage detector having a charge transistor smaller than an output transistor of the voltage regulator, providing a detection path for fast response, compensating undervoltage without large control current when loading changes from light to heavy.

Abstract: A voltage regulator including a transconductance amplifying unit, a transresistance amplifying unit, a feedback unit, a differential amplifying unit, and a compensation capacitor. The transconductance amplifying unit includes two inputs for receiving a feedback voltage and a reference voltage, and includes an output for outputting a current. The transresistance amplifying unit includes an input for receiving the current, and transforming the current into an output voltage. The feedback unit generates the feedback voltage with reference to the output voltage. The differential amplifying unit includes two inputs for receiving the feedback voltage and the reference voltage, and includes an output for outputting a differential voltage. The compensation capacitor is coupled between the output of the differential amplifying unit and the input of the transresistance amplifying unit.

Abstract: In one embodiment, a voltage reference circuit is configured to use two differentially coupled transistors to form a delta Vbe for the voltage reference circuit.

Abstract: Apparatuses, systems, and methods are disclosed for generating, regulating, and modifying various voltage levels on a semiconductor device using a current mirroring digital-to-analog voltage regulator. The voltage regulator operates by mirroring a reference current onto a selectable current level and controlling the selectable current level with a digital input to a plurality of switched CMOS devices connected in parallel. The switched CMOS devices generate the selectable current level responsive to the digital input and proportional to the reference current. The selectable current level is combined with an output of a voltage divider to generate a monitor signal. The monitor signal is compared to a reference voltage and the results of the comparison controls a charge pump to generate a pumped voltage. The pumped voltage is fed back to the voltage divider, which includes a feedback resistor and a reference resistor connected in series between the pumped voltage and ground.

Abstract: A voltage regulator for providing a regulated voltage is disclosed. The voltage regulator comprises an error amplifying module and a regulator. The error amplifying module provides a reference voltage, based on an output voltage to be regulated. The regulator provides a regulated output voltage based on the reference voltage. Voltage regulator provides stable output voltage against variations caused by power supply and load with a defined temperature coefficient.

Abstract: A voltage sensing circuit is capable of controlling a pumping voltage to be stably generated in a low voltage environment. The voltage sensing circuit includes a current mirror having first and second terminals, a first switching element configured to control current on the first terminal of the current mirror by a reference voltage, a second switching element configured to control current from the second terminal of the current mirror in response to a pumping voltage, and a third switching element configured to control current sources of the first and second switching elements to receive a negative voltage.

Abstract: Methods and apparatus are disclosed for providing stable voltage references from within a low dropout voltage regulator. Some embodiments utilize dependable semiconductor inherent attributes to generate a voltage reference, such as a band-gap voltage reference.

Abstract: Techniques for reliably and efficiently generating an output voltage for use within an electronic device, such as a memory system, are disclosed. A voltage generation circuit generates the output voltage. The voltage generation circuit includes regulation circuitry that controls regulation of the output voltage to maintain the output voltage at a substantially constant level. According to one aspect, regulation is provided through use of different feedback circuits. By selectively disabling one of the feedback circuits, power consumption can be reduced and the other of the feedback circuits can support the continued regulation of the output voltage. The voltage generation circuit is therefore able to operate in an accurate, stable and power efficient manner.

Abstract: A linear step-down voltage regulator is provided. The linear step-down voltage regulator is grounded with a ground terminal. The ground terminal is electrically connected to a digital ground terminal of a switching circuit. The linear step-down voltage regulator includes a pass element, a voltage dividing resistor, an error amplifier, a metal oxide semiconductor (MOS) transistor, and a low-pass filter. The employment of the low-pass filter effectively adjusts and restricts the switching noise to pass therethrough, so as to decrease the output of the switching noise and thus eliminating the problems due to the noise.

Abstract: A voltage regulator having an input voltage and adapted to supply a regulated output voltage, the regulator including an AB class amplifier and a power transistor having a non-drivable terminal coupled to the input voltage, a non-drivable terminal coupled to a reference voltage and a drivable terminal coupled to the output terminal of the amplifier; the amplifier is adapted to amplify the voltage difference between a further reference voltage and a fraction of the regulated voltage.

Abstract: A parallel circuit 27 of a frequency control circuit 11 is provided as an external circuit. Thereby, the charging time t1 depends on the characteristics of the circuit elements, which are provided in the package of a semiconductor device 70 and therefore subject to manufacturing variations of the semiconductor device 70. The discharging time t2 depends on the parallel circuit 27, which is provided external to the semiconductor device 70 and therefore can be selected to have appropriate characteristics after the semiconductor device 70 has been manufactured. The circuit constants of circuits are set so that the discharging time t2 that depends on the device characteristics of the external parallel circuit 27 is longer than the charging time t1 that depends on the device characteristics of the internal circuits of the semiconductor device 70.

Abstract: In a method and system for converting an alternating current (AC) input to a direct current (DC) output, an AC-DC adapter includes a rectifier module operable to receive the AC input and generate a first DC output. The AC-DC adapter includes a buck converter module operable to receive the first DC output and generate the DC output responsive to a control signal. A controller module, included in the AC-DC adapter is operable to receive a first feedback signal input indicative of a target voltage required by a load and a second feedback signal input indicative of the DC output to generate the control signal. The controller module adjusts the control signal responsive to the first and second feedback signal inputs so that the DC output is maintained to be within a predefined range of the target voltage.

Abstract: A voltage regulator output stage can include a power device whose body to source junction is forward biased using a MOSFET trigger. The forward biasing can advantageously reduce the threshold voltage of the power device, thereby effectively increasing its gate drive as well as its output current capability. Controlling the forward biasing using the MOSFET trigger provides minimal leakage, thereby ensuring that the output stage is commercially viable as well as performance enhanced.

Abstract: A voltage regulator including a voltage regulation unit and an over driving unit is provided. The voltage regulation unit outputs a corresponding output voltage according to an input voltage. The over driving unit is coupled between an input terminal and an output terminal of the voltage regulation unit and regulates the input voltage according to the comparison result between the output voltage and a reference voltage.

Abstract: A control circuit for a DC voltage supply is provided that includes a circuit, an error amplifier and modulator. The circuit is operable to measure a voltage difference between a negative voltage rail and a ground reference in the DC voltage supply. The circuit is further operative to create an offset voltage proportional with the measured voltage difference. The circuit is further yet operative to add the offset voltage to a reference voltage to create a modified reference voltage. The error amplifier has a first input coupled to receive the modified reference voltage and a second input coupled to a positive voltage rail in the DC voltage supply. The error amplifier further has an output. The modulator is coupled to the output of the error amplifier. The modulator is operative to maintain the positive rail at a select value corresponding to the modified reference voltage.

Abstract: A constant-voltage circuit in which a response speed for a sudden change of an input voltage or a sudden change of a load current can be fast are disclosed. In normal operating conditions, a first control circuit (error amplifier circuit) having an excellent direct-current characteristic controls operations of an output voltage control transistor and an output voltage is made a constant voltage. When the output voltage is suddenly decreased, before the first control circuit controls the operations of the output voltage control transistor by responding to the sudden decrease of the output voltage, an amplifier circuit having a high-speed response characteristic amplifies the change of the output voltage, and when the amplified voltage obtained by the amplification is suddenly decreased, a second control circuit controls the operations of the output voltage control transistor for a predetermined period. With this, the output voltage can be a constant voltage.

Abstract: Improved designs of an LDO voltage regulator with ultra low quiescent current are disclosed. According to one embodiment, an LDO voltage regulator is designed to completely cancel an intermediate gain stage while decreasing a quiescent current and to stabilize a loop circuit by means of two zeros introduced in a frequency transfer function thereof. Such a LDO voltage regulator does not increase the power consumption and applicable in many circuits used in electronic devices.

Abstract: An improved capacitive feedback circuit (20) comprises a feedback capacitor (23) having its output terminal connected to a high-impedance node (N). More particularly, the improved capacitive feedback circuit comprises a first branch (24) having a bias current source (25), an amplifying element (26), and a current sensor (27) connected in series, the amplifying element having a high-impedance control terminal (26c). The feedback capacitor (23) has its output terminal connected to said control terminal (26c). A current-to-voltage converting feedback loop (28) has a high-impedance output terminal (28c) connected to said feedback capacitor output terminal.

Abstract: Constant voltage regulator includes an output terminal, an output transistor, an output voltage controller, and a switching circuit. The output terminal outputs a first voltage to an external host apparatus. The output transistor outputs a current in accordance with a signal. The output voltage controller amplifies a difference between a reference voltage and a feedback voltage produced in proportion to the first voltage, and outputs the amplified voltage to the control gate of the output transistor. The switching circuit selectively outputs one of a second voltage greater than the first voltage and a third voltage greater than the second voltage to a substrate gate of the output transistor in response to an operation mode switchable between a first mode in which an output current to the external host apparatus is smaller than a predetermined value and a second mode in which the output current is greater than the predetermined value.

Abstract: A low dropout (LDO) regulator operates in wide input range. The LDO includes an N-type pass transistor and a P-type pass transistor for supplying power to the output terminal. The P-type pass transistor is connected with N-type pass transistor in parallel. Two error amplifiers control the gate terminals of the N-type pass transistor and P-type pass transistor to generate a first output voltage and a second output voltage. Thus, the first output voltage is generated when the input voltage is higher than a threshold voltage, and the second output voltage is generated when the input voltage is lower than the threshold voltage.

Abstract: Apparatuses, methods, and systems for effective power management distribution are provided. In an embodiment, a system for providing power to a circuit block comprises a power management unit (PMU) configured on a first substrate and an integrated circuit (IC) configured on a second substrate. The PMU includes a first regulator configured to step down an input voltage and output a first regulated voltage. The IC includes the circuit block and a second regulator configured to receive the first regulated voltage and output a second regulated voltage. The second power regulated voltage provides power to the circuit block. The first regulator is more efficient than the second regulator.

Abstract: A system for controlling mode crossover time in a power supply includes a power output element having a constant voltage control loop and a constant current control loop, the constant voltage control loop having a first error amplifier and the constant current control loop having a second error amplifier. An additional error amplifier is operatively coupled to a compensation capacitance associated with the second error amplifier, the additional error amplifier configured to cause the constant current control loop to provide an additional current to flow from the constant current control loop, thus causing the power output element to transition from a constant voltage mode to a constant current mode responsive to a programmed voltage value.

Abstract: A voltage regulator system is provided, which receives a first voltage and produces a regulated voltage. Such a device does not include any transistor supporting the first voltage, but does include transistors supporting at most a second voltage lower than the first voltage and includes division means, which include a first transistor connected in series with at least one second transistor, which division means receive the first voltage and generate the regulated voltage.

Abstract: A power converter system that includes a diagnostic system is presented. One example of a power converter system is an audio amplifier system, such as a switch mode amplifier. The diagnostic system in the power converter may collect data indicative of signals in the power converter system and analyze the collected data. The collection and analysis of the data may be user defined (such as multiple measurements taken over a predetermined period) or may be defined by operation of the power converter system (such as an overcurrent or voltage clipping in the power converter system). The analysis of the collected data may be used to determine one or more potential problems in the power converter system, and to modify operation of the power converter system.

Abstract: In one embodiment, a linear regulator is formed with a variable miller compensation circuit that varies a zero of the linear regulator proportionally to a load current supplied by the regulator.

Abstract: A voltage regulator includes an amplifier having first and second outputs, a feedback path coupled between a first input and the first output of the amplifier, and a feed-forward path between the second output of the amplifier and a switch coupled to a reference potential. In operation, a first control signal from the second output of the amplifier is generated based on a comparison of a reference signal and a feedback signal into the first input of the amplifier. The first control signal controls the switch to maintain a substantially constant supply voltage. A second control signal is generated along the feedback path to control controls the amount of supply voltage.

Abstract: The present invention provides a regulator circuit that can fast-respond to a variation in load current and supply a sufficient drive current so as to be capable of generating a stable internal source voltage. The regulator circuit includes a preamplifier circuit that detects and amplifies a different between a reference voltage and an internal source voltage, a clamp circuit that limits the amplitude of an output of the preamplifier circuit, a main amplifier circuit that amplifies the amplitude-limited output of the preamplifier circuit, and a driver circuit that outputs the internal source voltage according to the output of the main amplifier. Even though the internal source voltage varies abruptly, the regulator circuit does not oscillate owing to the effect of the clamp circuit.

Abstract: A trimming circuit which comprises a shunt circuit having two shunt resistors and two shunt ON/OFF switches and connected in parallel with a series resistor circuit. The middle point of the shunt circuit is connected to a connection point of the series resistor circuit, the resistance ratio thereof with respect to the connection point being equal to the resistance ratio of the shunt resistors.

Abstract: In an embodiment of the present invention there is provided a device for providing a control voltage that is substantially equivalent to a reference voltage used by a power supply. The device includes a first electronic circuit that is arranged to be connected to a ground via a resistor and to produce a supplementary voltage that is dependant on a resistance of the resistor. The device also includes a second electronic circuit that is arranged to present a resistance to a current in order to provide the control voltage and to receive an output voltage of the power supply and the supplementary voltage to effect the current.

Abstract: Feedforward compensated systems and methods for their use in disturbance rejection in switching power converters and other systems. In one instance, a compensating component receives a sensed output and provides a duty cycle adjustment signal, the duty cycle adjustment signal being obtained from signals indicative of present and past load current variations. In another instance, an adaptive compensating component receives a sensed output and provides an adjustment signal for compensating for load variations. A compensator design component receives the digitized sensed output and of provides compensating component parameters to the adaptive compensating component; the compensator design component including a learning function.

Abstract: An area-efficient capacitor-free low-dropout regulator based on a current-feedback frequency compensation technique is disclosed. An implementation of a current feedback block with a single compensation capacitor is used to enable capacitance reduction. The resultant low-dropout regulator does not generally require an off-chip capacitor for stability and is particularly useful for system-on-chip applications.

Abstract: A series regulator for supplying a stable output voltage to a load has a differential amplifier circuit and an output stage. The output stage has an output control transistor that supplies the output voltage in accordance with a control signal, and a voltage divider circuit that divides the output voltage and outputs the divided voltage. The differential input stage includes a differential pair (source-coupled pair) of two NMOS transistors, an NMOS transistor, and a current mirror circuit formed by PMOS transistors. The differential input stage detects a differential voltage between a reference voltage and the divided voltage output from the voltage divider circuit. The differential amplifier circuit also has an amplification stage including a PMOS transistor that has a resistor connected between its gate and drain and that has its drain connected to a node, and an NMOS transistor that supplies a current proportional to a constant current to the PMOS transistor.

Abstract: In a method and system for regulating an output voltage, a linear voltage regulator (LVR) includes an adjustable shunt regulator (ASR) having a limited gain, a feedback circuit (FC), and a compensation resistor (CR). The limited gain causes the output voltage of the ASR to change in response to a change in an input current of the ASR. The FC generates a feedback voltage reference in proportion to the output voltage, the feedback voltage reference being provided to the ASR to control the output voltage. The CR is coupled to the ASR and the FC. The input current flows through the CR to provide a compensating voltage across the CR. The compensating voltage is provided to the feedback circuit to compensate the limited gain, thereby providing the output voltage that is substantially independent of the input current.

Abstract: A power measurement system is disclosed for use on an integrated circuit for measuring the power used by the integrated circuit. The power measurement system includes a low-dropout voltage regulator and a signal input unit. The low-dropout voltage regulator includes a power transistor that couples a supply voltage to a circuit to be powered by the supply voltage, and the low-dropout voltage regulator provides an internal adjustment signal (Vsen) for adjusting the internal resistance of the power transistor. The signal input unit receives the internal adjustment signal (Vsen) and provides a power measurement signal responsive to the internal adjustment signal (Vsen).

Abstract: A circuit arrangement (1) for the regulation of a current (IL) through a load (RL) comprises: a resistance (RS), through which a load current (IL) flows and across which a voltage (VS) drops, which serves as a control variable (X) for the regulation of the load current (IL), a tapping point (P) for a reference voltage (Vref), which serves as a command variable (W) for the regulation of the load current (IL), and a differential amplifier for the amplification of the control deviation (W?X) between command variable (W) and control variable (X).

Abstract: A voltage regulator circuit comprises an amplifier, bias network and startup circuit. The bias network is configured to generate a bias voltage for setting a bias current in the amplifier. The startup circuit is configured to mirror the amplifier bias current and to assist the bias network in setting the amplifier bias current based on the mirrored amplifier bias current until the bias voltage approximates a desired level.

Abstract: A voltage regulator circuit is operated by enabling a bias network operable to set a bias current in an amplifier. A startup circuit is connected to the bias network, the startup circuit operable to assist the bias network in setting the amplifier bias current during a startup period. The startup circuit is disconnected from the bias network responsive to the startup period lapsing while the voltage regulator circuit is enabled for resetting the startup circuit to an initial state. The bias network may be disabled to reduce the amplifier bias current. Subsequent re-enablement of the bias network is prevented until the amplifier is reliably disabled.

Abstract: Effective power regulation may be achieved for a field instrument that derives power from a communication signal. In particular aspects, a system and process for power regulation include the ability to receive a communication signal and adjust the voltage supplied to a power converter based on the current of the communication signal. The system and method also include the ability to convert power of the communication signal with the power converter.

Abstract: A constant voltage circuit which is capable of quickly responding to a sudden change of an output voltage includes an output transistor, and first and second error amplifiers. The output transistor outputs a power with an output voltage and an output current to a load. The first error amplifier is configured to increase a response speed with respect to changes of the output voltage in accordance with an increase of the output current so as to control operations of the output transistor. The second error amplifier has a response speed faster than the first error amplifier with respect to changes of the output voltage, and is configured to decrease a gain thereof in response to a drain current of the output transistor.

Abstract: Circuits and methods to provide an LDO output stage implemented with low-voltage devices and still allowing higher voltage levels have been achieved. The output stage has been built using two low voltage MOS devices in series. During the time the regulator is in active mode the second MOS device acts as a small resistor in series to the pass device. During power down this second device actively protects the MOS pass device and itself from high voltage stress levels. This is achieved by a robust regulating mechanism that compensates leakage currents. These leakage currents normally determine the different potentials of the output stage during power down. Although the second transistor presents a resistive obstacle during active mode the total chip area required is smaller compared to a single pass device tolerating e.g. 5 Volts.