Voltage regulator

Abstract

A voltage regulator may include an output node, a regulator tube, a first feedback circuit, and a second feedback circuit. The output node is operable for connection to a load. The regulator tube is operable to transfer a current to an output node based on a voltage applied to the regulator tube, where the regulator tube includes a p-channel transistor. The first feedback circuit is operable to regulate a voltage applied to the regulator tube based on the output node voltage. The second feedback circuit is operable to regulate a voltage applied to the regulator tube based on a change in the output node voltage.

Description

[0001] Cross - Reference to Related Applications

[0002] This application claims the benefit of U.S. Provisional Patent Application No. 63 / 381,274, filed on October 27, 2022, the disclosure of which is incorporated herein by reference in its entirety. Technical Field

[0003] Examples discussed in this disclosure relate to a voltage regulator, and particularly to feedback devices, circuits, and pass devices for a load. Background Art

[0004] Unless otherwise indicated herein, the materials described herein are not prior art to the claims of this application and are not admitted to be prior art merely by virtue of their inclusion in this section.

[0005] Voltage regulators (e.g., low dropout (LDO) voltage regulators (LDOs)) can be used in various applications, such as for lower power operation. In some cases, on - chip LDO voltage regulators can be used to reduce the area and cost associated with LDO voltage regulators.

[0006] The subject matter claimed in this disclosure is not limited to examples for solving any disadvantages or operating only in environments such as those described above. Instead, this background is provided only to illustrate an example technical field in which some examples described in this disclosure may be practiced. Summary of the Invention

[0007] A voltage regulator may include: an output node for connection to a load; a pass device operable to transfer current to the output node based on a voltage applied to the pass device; a first feedback circuit operable to regulate the voltage applied to the pass device based on the output node voltage; and a second feedback circuit operable to regulate the voltage applied to the pass device based on a change in the output node voltage. The pass device may include a p - channel transistor.

[0008] A voltage regulator may include: an output node operable to connect to a load; a pass device operable to transfer current to the output node based on a voltage applied to the pass device; a first feedback circuit operable to regulate the voltage applied to the pass device based on the output node voltage; a second feedback circuit operable to reduce the impedance of the output node; and a circuit operable to increase the phase margin of the voltage regulator. The pass device may include a p - channel transistor.

[0009] A voltage regulator may include: an output node operable to be connected to a load; an adjustment transistor operable to transfer current to the output node based on a voltage applied to the adjustment transistor; a first feedback circuit operable to regulate the voltage output to the adjustment transistor based on the output node voltage; a second feedback circuit including a first n-channel transistor of the second feedback circuit and a second n-channel transistor of the second feedback circuit; and a circuit including one or more circuit transistors in a mirror configuration to increase one or more of the power supply rejection ratio (PSRR) bandwidth or transient response of the voltage regulator. The adjustment transistor may include a p-channel transistor.

[0010] The objectives and advantages of these examples will be achieved and attained at least by the elements, features, and combinations particularly pointed out in the claims.

[0011] The foregoing general description and the following detailed description are given as examples and are explanatory, and are not limiting of the claimed invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Exemplary instances will be described and explained below by using the drawings and with additional features and details, wherein:

[0013] Figure 1 An example voltage regulator circuit is shown;

[0014] Figure 2 Another example voltage regulator circuit is shown;

[0015] Figure 3 Voltage and current variations in the example voltage regulator circuit are shown; and

[0016] Figure 4 Another example voltage regulator circuit is shown;

[0017] Figure 5 An example process flow of a voltage regulator described according to at least one embodiment of the present disclosure is shown.

[0018] Figure 6 An example process flow of a voltage regulator described according to at least one embodiment of the present disclosure is shown.

[0019] Figure 7 An example process flow of a voltage regulator described according to at least one embodiment of the present disclosure is shown.

[0020] Figure 8 A diagram of an example form of a machine of a computing device is shown, in which a set of instructions may be executed to cause the machine to perform any one or more of the methods discussed herein. DETAILED DESCRIPTION

[0021] A voltage regulator, such as a low dropout (LDO) voltage regulator, can be used to provide power for the low-power operation of electronic components. The LDO voltage regulator can be constructed using a metal-oxide-semiconductor field-effect transistor (MOSFET). In some cases, the LDO voltage regulator can include a p-channel MOSFET transistor (referred to herein as a p-channel metal-oxide-semiconductor (PMOS) transistor). For example, the LDO voltage regulator can include a PMOS transistor as a regulating transistor. Using a PMOS transistor can provide lower power operation because the difference between the supply voltage and the output voltage can be less than the difference between the supply voltage and the output voltage when using an n-channel MOSFET transistor (referred to herein as an n-channel metal-oxide-semiconductor (NMOS) transistor).

[0022] Using a PMOS transistor as a regulating transistor in an LDO voltage regulator can result in a high impedance at the output mode of the LDO voltage regulator. Alternatively or additionally, using a PMOS transistor as a regulating transistor can result in the main pole being outside the LDO voltage regulator, and thus the main pole is affected by changes in the load capacitance and the equivalent load resistance of the load connected to the LDO voltage regulator.

[0023] Some examples described in the present disclosure provide an LDO voltage regulator with additional circuitry to reduce the impedance at the output. Alternatively or additionally, some examples describe an LDO voltage regulator with additional circuitry that allows the main pole of the LDO voltage regulator to be inside the LDO voltage regulator. For example, the LDO voltage regulator can include first and second feedback circuits. The first feedback circuit can include an amplifier and a feedback voltage provided to the amplifier. The amplifier can regulate the voltage, thereby regulating the regulating transistor and thus the voltage at the output node of the LDO voltage regulator.

[0024] In some examples, the second feedback circuit can include a voltage follower configuration and can act as a buffer between the amplifier and the regulating transistor of the LDO voltage regulator. In these and other examples, the second feedback circuit can be used to create a low impedance at the output of the regulating transistor.

[0025] Alternatively or additionally, when no current is being drawn by the load of the LDO voltage regulator, the second feedback circuit can draw current from the regulating transistor, which can help improve the stability of the LDO voltage regulator and help maintain the regulating transistor in the saturation region when no current is being drawn by the load.

[0026] Alternatively or additionally, the second feedback circuit can isolate the regulating transistor and the output of the amplifier from the first feedback circuit, which can allow the main pole to be configured for the LDO voltage regulator without being affected by load variations.

[0027] Alternatively or additionally, the second feedback circuit can help improve the transient response of the LDO regulator. Alternatively or additionally, the second feedback circuit can help improve the power supply rejection ratio (PSRR) of the LDO regulator at higher frequencies, such that the PSRR of the LDO regulator reaches an equivalent PSRR level as when an N-channel transistor is used as the regulating transistor. In some examples, the second feedback circuit can allow the regulating transistor to be a p-channel transistor while allowing the regulator circuit to emulate an n-channel transistor of the regulating transistor.

[0028] As Figure 1 shown, the regulator circuit 100 can include one or more of an output node 112, a regulating transistor 110, a first feedback circuit 130, a second feedback circuit 140, or a circuit 150. The output node 112 is operable to be connected to a load 120 (which can be connected to ground 121). The regulating transistor 110 is operable to transfer current to the output node based on a voltage applied to the regulating transistor. The regulating transistor 110 can be a p-channel transistor. Alternatively or additionally, the regulating transistor 110 can be an n-channel transistor. The first feedback circuit 130 is operable to regulate the voltage applied to the regulating transistor 110 based on the voltage of the output node 112. The second feedback circuit 140 is operable to regulate the voltage applied to the regulating transistor 110 based on a change in the voltage of the output node 112. For purposes of this disclosure, "connected" can be "directly connected" or "indirectly connected". As Figure 1 shown, components can be connected together (directly or indirectly).

[0029] The regulator circuit 100 can use the output node 112 to provide voltage and / or current to the load 120. The amount of current can depend on the operation of the load 120. The load 120 can be a circuit capable of performing any type of operation that uses the voltage level provided by the regulator circuit 100 and / or the current level provided by the regulator circuit 100. For example, the load 120 can be a voltage controlled oscillator.

[0030] The voltage provided to the load 120 at the output node 112 can be equal to or approximately equal to a set voltage. In these and other examples, the regulator circuit 100 can be used to regulate the amount of current provided to the output node 112 to maintain the voltage on the output node 112 at or approximately at the set voltage. For purposes of this disclosure, "approximately" can refer to a value within an error range less than one or more of: 10% of the value, 8% of the value, 5% of the value, 3% of the value, 2% of the value, 1% of the value, etc.

[0031] The regulating transistor 110 can be an active device that is used to transfer current from the power supply VCC2 142 to the output node 112 and the load 120. For example, the regulating transistor 110 can transfer a certain amount of current based on a voltage signal provided by the second feedback circuit 140. In some examples, the voltage signal can be based on the voltage signal generated by the first feedback circuit 130. In these and other examples, the second feedback circuit 140 can be configured as a buffer circuit between the first feedback circuit 130 and the output node 112.

[0032] The voltage signal provided to the regulating transistor 110 from the second feedback circuit 140 can be based on a change in voltage at the output node 112. In some examples, the second feedback circuit 140 can regulate a change in the voltage signal provided to the regulating transistor 110 before the first feedback circuit 130 regulates the change in the voltage signal. In these and other examples, the second feedback circuit 140 can regulate an initial change in the voltage signal provided to the regulating transistor 110, and after the change in the voltage signal provided by the second feedback circuit 140, the first feedback circuit 130 can provide a change in the voltage signal that can be buffered by the second feedback circuit 140. A change in the voltage signal provided to the regulating transistor 110 can cause the regulating transistor 110 to adjust the amount of current provided to the output node 112, thereby adjusting the voltage at the output node 112.

[0033] The regulating transistor 110 can be a metal-oxide-semiconductor field-effect transistor (MOSFET). In these and other examples, the regulating transistor 110 can be a p-channel MOSFET device. Using a p-channel MOSFET device as the regulating transistor 110 can allow the voltage regulator circuit 100 to have a lower voltage drop. For example, using a p-channel MOSFET device can allow the voltage difference between VCC2 142 and the output node 112 to be at the saturation voltage of the p-channel MOSFET device, which can be lower than the voltage difference when an n-channel MOSFET device is used as the regulating transistor 110. Additionally, based on the configuration of the regulating transistor 110, the common collector voltage 1 (VCC1) 128 and the common collector voltage 2 (VCC2) 142 can be the same or approximately the same. Alternatively or additionally, VCC1 128 and VCC2 142 can be the same power supply rather than different power supplies.

[0034] The first feedback circuit 130 can be used to obtain an indication of the voltage at the output node 112. The first feedback circuit 130 can compare the indication of the voltage at the output node 112 with a set voltage 126. The set voltage 126 can be a selected voltage of the output node 112, or a voltage determined based on the selected voltage of the output node 112. The first feedback circuit 130 can generate a first output voltage 132, and the first output voltage 132 can adjust the voltage signal provided to the regulating transistor 110. In these and other examples, the first output voltage can be provided to the second feedback circuit 140 and the circuit 150. The first feedback circuit 130 can be used to receive feedback from the output node 112. The first feedback circuit 130 can be connected to ground 131.

[0035] The second feedback circuit 140 can be used to obtain the first output voltage 132 from the first feedback circuit 130. The second feedback circuit 140 can generate a voltage signal 114 provided to the regulating transistor 110 based on the first output voltage 132. In these and other examples, the second feedback circuit 140 can act as a buffer circuit between the first feedback circuit 130 and the regulating transistor 110. Thus, the second feedback circuit 140 can adjust the voltage signal 114 in response to the first output voltage 132 provided by the first feedback circuit 130. The second feedback circuit can be connected to ground 141.

[0036] The second feedback circuit 140 can be used to draw or supply current from the regulating transistor 110. As a result, when the current drawn from the load 120 is less than a selected amount, the second feedback circuit 140 can help maintain the regulating transistor 110 in the saturation operating region because the second feedback circuit 140 can draw current from the regulating transistor 110. For the purposes of this disclosure, the "selected amount of current" can be less than one or more of 100 mA, 10 mA, 1 mA, 0.1 mA, 1 μA, etc.

[0037] The second feedback circuit 140 can be used to help reduce the impedance at the output node 112 by using a voltage follower. For example, the second feedback circuit 140 can use a voltage follower configuration of MOSFET transistors to reduce the impedance at the output node 112, and the MOSFET transistors can be p-channel transistors or n-channel transistors. In some examples, reducing the impedance can improve the transient performance of the voltage regulator circuit 100.

[0038] The second feedback circuit 140 can be used to promote the dominant pole of the voltage regulator circuit 100, and the dominant pole can promote an improvement in stability in response to load changes. The improvement in stability can be measured relative to the stability when the dominant pole is not used.

[0039] The second feedback circuit 140 can buffer the circuit 150 from the output node 112. In this way, the second feedback circuit 140 can allow the circuit 150 to provide a dominant pole for the voltage regulator circuit 100 with respect to the frequency response of the voltage regulator circuit 100 and reduce the impact of changes in the load 120 with respect to the frequency response of the voltage regulator circuit 100. For example, due to the second feedback circuit 140, the pole of the voltage regulator circuit 100 located at the output node 112 can experience a lower impedance and thus can be located at a higher frequency, allowing the pole of the circuit 150 to become the dominant pole.

[0040] The second feedback circuit 140 can be used to regulate the output node 112 based on the change in the first output voltage 132 from the first feedback circuit 130 and the voltage at the output node 112.

[0041] In some examples, the second feedback circuit 140 can further be used to regulate the voltage signal 114 provided to the regulating transistor 110 independently of the first feedback circuit 130. In these and other examples, the second feedback circuit 140 can adjust the voltage signal provided to the regulating transistor 110 without changing the first output voltage 132 provided from the first feedback circuit 130 to the second feedback circuit 140. Alternatively or additionally, in addition to the change in the first output voltage 132 provided from the first feedback circuit 130 to the second feedback circuit 140, the second feedback circuit 140 can also be operative to regulate the voltage signal 114. For example, in response to a change in the voltage at the output node 112, one or more of the first feedback circuit 130 and the second feedback circuit 140 can direct a response to the voltage signal 114 provided to the regulating transistor 110. In these and other examples, the second feedback circuit 140 can have a faster response than the first feedback circuit 130 and can regulate a change in the voltage signal 114 before the first feedback circuit 130 regulates the change in the voltage signal 114. In these and other examples, after regulating the change, the second feedback circuit 140 can obtain the first output voltage 132 from the first feedback circuit 130. The second feedback circuit 140 can adjust the voltage signal 114 based on one or more of the first output voltage 132 from the first feedback circuit 130 and based on the change in the voltage at the output node 112 determined by the second feedback circuit 140 independently of the first feedback circuit 130. Thus, one or more of the first feedback circuit 130 and the second feedback circuit 140 can act as a gain loop for regulating the regulating transistor 110.

[0042] The circuit 150 is operable to provide a dominant pole for the voltage regulator circuit 100. Based on the placement of the circuit 150 between the second feedback circuit 140 and the gate of the regulating transistor 110, the effect of current variations of the load 120 on the pole generated by the circuit 150 can be reduced. The circuit 150 is also used to generate a zero for the voltage regulator circuit 100. The zero can help reduce the effect of the pole, thereby increasing the phase margin of the voltage regulator circuit 100.

[0043] The circuit 150 can be connected to a first output voltage 132 received from the first feedback circuit 130. The circuit can be connected to the second feedback circuit 140 and the regulating transistor 110 (e.g., via connection 152). In some examples, the circuit 150 can include Figure 2 the elements shown. Alternatively or additionally, the circuit 150 can include Figure 4 the elements shown.

[0044] Without departing from the scope of the present disclosure, modifications, additions, or omissions can be made to the voltage regulator circuit 100. For example, the voltage regulator circuit 100 can not include the circuit 150.

[0045] Alternatively or additionally, the voltage regulator circuit 100 can include one or more of an output node 112, a regulating transistor 110, a first feedback circuit 130, a second feedback circuit 140, or the circuit 150. The output node 112 is operable to be connected to the load 120. The regulating transistor 110 is operable to transfer current to the output node 112 based on a voltage 142 applied to the regulating transistor 110. The regulating transistor 110 can include a p-channel transistor. The first feedback circuit 130 is operable to regulate the voltage 142 applied to the regulating transistor 110 based on the voltage of the output node 112. The second feedback circuit 140 is operable to reduce the impedance of the output node 112. The circuit 150 can be used to increase the phase margin of the voltage regulator circuit 100. The first feedback circuit 130 can include one or more of a first resistor, a second resistor, or an amplifier. The second feedback circuit 140 can include a voltage follower.

[0046] As Figure 2As shown, the voltage regulator circuit 200 may include one or more of an output node 212, a load 220, a regulating transistor 210, first feedback circuits 230a, 230b, a second feedback circuit 240, or a circuit 250. The output node 212 is operable to be connected to the load 220. The regulating transistor 210 is operable to transfer current to the output node 212 based on a voltage applied to the regulating transistor 210. The regulating transistor 210 may include a p-channel transistor and / or an n-channel transistor. The first feedback circuits 230a, 230b may be used to regulate the voltage applied to the regulating transistor 210 based on the voltage of the output node 212. The second feedback circuit 240 may regulate the voltage applied to the regulating transistor 210 based on a change in the voltage of the output node 212.

[0047] The voltage regulator circuit 200 may be arranged according to at least some of the examples described herein. The components in the voltage regulator circuit 200 may be connected as Figure 2 shown. Those with arrows pointing to the transistor body are p-channel transistors (e.g., transistors 243, 208), and the arrowed pins are the sources (e.g., sources 243a, 208a for transistors 243, 208 respectively). Those with arrows away from the transistor body are n-channel transistors (e.g., transistors 245, 246, 247), and the arrowed pins are the sources (e.g., sources 245a, 247a, 246a).

[0048] The transistor 243 may include a source 243a, a gate 243b, and a drain 243c. The transistor 208 may include a source 208a, a gate 208b, and a drain 208c. The transistor 245 may include a source 245a, a gate 245b, and a drain 245c. The transistor 246 may include a source 246a, a gate 246b, and a drain 246c. The transistor 247 may include a source 247a, a gate 247b, and a drain 247c.

[0049] The regulating transistor 210, the output node 212, the load 220, the first feedback circuits 230a, 230b, the second feedback circuit 240, and the circuit 250 may be example implementations of the regulating transistor 110, the output node 112, the load 120, the first feedback circuit 130, the second feedback circuit 140, and the circuit 150 as described with reference to Figure 1 the foregoing. The present disclosure contemplates other implementations of the regulating transistor 110, the output node 112, the load 120, the first feedback circuit 130, the second feedback circuit 140, and the circuit 150 that may be performed as described in the present disclosure.

[0050] The regulating transistor 210 may include a transistor 208, whose drain 208c is connected to the first feedback circuits 230a, 230b and the second feedback circuit 240. The voltage supplied to the gate 208b may be a power dissipation (PD) gate voltage (e.g., VDDA_PD 242). The voltage supplied to the gate 208d may be an amount ranging from about 1V to about 200V, or from about 100mv to about 5000mv, or from about 0.1mV to about 100mV. The regulating transistor 210 may be connected to an output node 212, and the output node 212 may have a voltage of ldo_vout. The voltage of ldo_vout may be an amount ranging from about 1V to about 200V, or from about 100mv to about 5000mV, or from about 0.1mV to about 100mV. The load 220 may have a resistor 222 and a capacitor 224 as shown in the figure, and may be connected to the output node 212. The resistance of the load may be an amount ranging from about 1Ω to about 1000Ω, or from about 100mΩ to about 5000mΩ, or from about 0.1mΩ to about 100mΩ. The capacitance of the load may be an amount ranging from about 0.1μF to about 100μF, or from about 1μF to about 20μF, or from about 1μF to about 10μF. By using a PMOS device as the regulating transistor 210, the ldo_vout voltage may be closer to the rail voltages VDDA_AMP and VDDA_PD compared to when using an NMOS device. The ldo_vout voltage may be set to an amount less than or equal to the voltage across the regulating transistor 210 (i.e., to VDDA_PD). Additionally, given the configuration of the regulator circuit 200, the rail voltages VDDA_AMP and VDDA_PD may be equal or approximately equal. In one example, one or more of the rail voltages may be from about 1V to about 200V, or about 100mV to about 5000mV, or about 0.1mV to about 100mV.

[0051] The first feedback circuits 230a, 230b may include one or more of a first resistor 238a, a second resistor 238b, or an amplifier 233. The output of the voltage divider circuit in 230b may be input to the amplifier 233 at the positive terminal 234a. The current across the first resistor 238a and the second resistor 238b may be the current 234i. The current 234i may be from about 1A to about 100A, or about 100μA to about 5000mA, or about 1μA to about 1000mA. The second terminal 232 (e.g., the negative terminal) of the amplifier 233 may be used to receive the voltage Vbg. The voltage Vbg may be from about 1V to about 200V, or about 100mv to about 5000mV, or about 0.1mV to about 100mV.

[0052] Using the first resistor 238a and the second resistor 238b as a voltage divider, the first feedback circuit is used to generate the voltage feedback 234b to be input to the amplifier 233. That is, the first feedback circuits 230a, 230b may include the first resistor 238a, the second resistor 238b, and the amplifier 233. The first resistor 238a and the second resistor 238b may be configured in the form of a voltage divider and are operable to generate the voltage feedback 234b based on the ido_vout voltage of the output node 212. The voltage feedback 234b may be provided to the first terminal of the amplifier 234a. The second terminal 232 (e.g., the negative terminal) of the amplifier may be provided with a constant voltage reference Vbg or an equivalent voltage, which may be a set voltage. The amplifier 233 may output Vout-amp based on the voltage feedback 234b and the voltage Vbg. The amplifier 233 may be connected to the second feedback circuit 240 and the circuit 250 through the connection 236.

[0053] The second feedback circuit 240 may include one or more of the transistors 245, 246, 247 or the resistor 244. The transistor 246 may be configured in a voltage follower configuration, wherein the drain 246c and the gate 246b of the transistor 246 are directly connected to the output node 212. The configuration of the transistor 246 may reduce the impedance of the output node 212. In addition, the transistor 246 and the transistor 247 may draw current from the regulating transistor 210 to maintain the regulating transistor 210 in the saturation region.

[0054] The transistor 245 may include a gate 245b connected to the first feedback circuits 230a, 230b and a drain 245c connected to the regulating transistor 210. In these and other examples, the output voltage at the connection 236 of the amplifier 233 of the first feedback circuits 230a, 230b may be provided to the gate 245b of the transistor 245. The transistor 245 may regulate the current flowing through the transistor 245, thereby regulating the PD gate voltage provided to the regulating transistor 210. In this way, the second feedback circuit 240 may regulate the regulating transistor 210 based on the output of the first feedback circuits 230a, 230b. The transistor 246 may act as a current source to draw the current i2 - i1 246i, and the current i2 - i1 246i may be a combination of the current i1 through the transistor 243 and the current i2 247i through the transistor 247. The transistor 247 may be biased by the voltage nbias. The voltage nbias may be from about 1V to about 100V, or from about 100mv to about 2500mV, or from about 0.1mV to about 50mV.

[0055] Transistors 245 and 246 can have similar characteristics. For example, the sizes of transistors 245 and 246 can be equal, such that transistors 245 and 246 have similar lengths and widths. In these and other examples, the sizes of transistors 245 and 246 can be designed to have a conductance (e.g., gm) sufficient to reduce the impedance of output node 212 to a value that provides proper operation of the voltage regulator circuit 200. This conductance can be from about 1 mS to about 1000 mS, or from about 1 μS to about 100 mS, or from about 1 mS to about 50 mS.

[0056] Transistor 243 can act as a current source based on the bias at gate 243b to draw current i1 243i. Current i1 243i can be the current flowing through transistor 245 to bias transistor 245. Resistor 244 can be used to provide a relatively small bias current for transistor 245. For example, in some cases, such as when a load is not connected to output node 212, transistor 245 may not conduct current. In such a case, resistor 244 can provide current 244i to allow transistor 245 to be biased and to allow operation of the second feedback circuit 240 when a load is not connected to output node 212. The current 246i flowing into transistor 246 can be approximately equal to the difference between the current i2 247i flowing through transistor 247 and the current i1 243i flowing into transistor 243.

[0057] Circuit 250 can include one or more capacitors 252 or resistors 254. This circuit can be used to increase the phase margin of the voltage regulator based on one or more of the main poles or zeros of the voltage regulator. That is, circuit 250 can be operable to provide poles and zeros for the voltage regulator circuit 200. Circuit 250 can include capacitor C1 252 and resistor 254. Based on the positions of other poles in the voltage regulator circuit 200 and the maximum capacitance of the load that the voltage regulator circuit 200 can support, the value of capacitor C1 252 can be selected to create a main pole in the voltage regulator circuit 200. The capacitance of capacitor C1 252 can be from about 1 Ω to about 1000 Ω, or from about 100 mΩ to about 5000 mΩ, or from about 0.1 mΩ to about 100 mΩ. Resistor 254 can be selected to place the zero at a unity gain frequency close to the pole created by the capacitance of capacitor C1 252. As a result, the phase margin of the voltage regulator circuit 200 can be increased by using resistor 254. Resistor 254 can have a resistance value from about 1 Ω to about 1000 Ω, or from about 100 mΩ to about 5000 mΩ, or from about 0.1 mΩ to about 100 mΩ.

[0058] By positioning the second feedback circuit 240 between the circuit 250 and the output node 212, the second feedback circuit 240 can buffer the circuit 250, such that the influence of capacitance variations of the load 220 on the circuit 250 is reduced. Additionally, in these and other examples, since the circuit 250 is included in the voltage regulator circuit 200, the zero generated by the first resistor 238a and / or the second resistor 238b may not be the dominant zero, and thus including the circuit 250 can allow for an increase in the resistance value of the first resistor 238a and / or the second resistor 238b.

[0059] Without departing from the scope of the present disclosure, the voltage regulator circuit 200 may be modified, added to, or omitted. For example, the voltage regulator circuit 200 may not include the circuit 250. Alternatively or additionally, the circuit 250 may not include the resistor 254 and / or the capacitor 252.

[0060] In another example, the voltage regulator circuit 200 may include an output node 212 that is operable to be connected to a load 220. The regulating transistor 210 is operable to transfer current to the output node 212 based on a voltage applied to the regulating transistor 210. The regulating transistor may be a p-channel transistor. The first feedback circuits 230a, 230b are operable to regulate the voltage applied to the regulating transistor 210 based on the voltage of the output node 212. The second feedback circuit 240 may be configured to reduce the impedance of the output node 212. The circuit 250 is operable to increase the phase margin of the voltage regulator circuit 200.

[0061] The first feedback circuit may include a first resistor 238a, a second resistor 238b, and an amplifier 233. The circuit 250 may include one or more of a capacitor 252 or a resistor 254.

[0062] As Figure 3 shown, the voltage regulator circuit 300 may include an output node 312, a regulating transistor 310, one or more of a first feedback circuit 330a, 330b, or a second feedback circuit 340. The output node 312 is operable to be connected to a load (which may include a variable resistor 326). The regulating transistor 310 is operable to transfer current to the output node 312 based on a voltage 342 applied to the regulating transistor 310. The regulating transistor may include a transistor 308 (e.g., a p-channel transistor). The transistor 308 may include a source 308a, a gate 308b, and a drain 308c. The first feedback circuits 330a, 330b are operable to regulate the voltage 342 applied to the regulating transistor 310 based on the voltage of the output node 312. The second feedback circuit 340 is operable to regulate the voltage applied to the regulating transistor based on a change in the voltage of the output node 312.

[0063] The voltage and current variations can be arranged according to at least some of the examples described herein. The voltage regulator circuit 300 can be similar to Figure 2 the voltage regulator circuit 200. The voltage regulator circuit 300 can be configured using the voltages, resistances, capacitances, conductances, currents, etc. described with reference to Figure 2 .

[0064] The second feedback circuit 340 can include an alternating current (AC) feedback loop, which can be operable to facilitate dynamic current to increase the transient response of the voltage regulator circuit 300. For example, the second feedback circuit 340 can be an AC feedback loop that helps the movement of dynamic current to improve the transient response of the voltage regulator circuit 300. For example, the voltage regulator circuit 300 may not draw the load current 326i. For example, the load current can be close to zero (e.g., less than one or more of 10 mA, 1 mA, 0.1 mA, 0.01 mA, 1 μA, etc.). In this case, when the load current 326i starts to be drawn by the load 320, the load current 326i increases rapidly. When the load current 326i increases, the load voltage 326v can decrease, which can decrease Vgs 346v. The decrease in Vgs 346v can decrease the current 346i, which can facilitate the transistor 345 to provide additional current to maintain the current i2 345i. When the transistor 345 provides additional current, i1 345i, 343i can increase, which can cause the PD_gate voltage 344v to decrease. Decreasing the PD_gate voltage 344v can increase the Vgs of the transistor 308, which can increase the current 308i and increase the subsequent ldo_vout 326vv to a higher level to compensate for the previous decrease in ldo_vout 326v. Therefore, the second feedback circuit 340 can operate independently of the first feedback circuits 330a, 330b to stabilize the voltage of ldo_vout. When i_load rapidly decreases to stabilize ldo_vout, the second feedback circuit 340 can operate in a similar manner.

[0065] The second feedback circuit 340 can include a transistor 343, which can include a source 343a, a gate 343b, and a drain 343c. The current i1 343i can flow through the transistor 343. The transistor 343 can be in parallel with a resistor 344. The resistor 344 can facilitate the voltage PD-Gate(V) 344v. PD-Gate(V) 344v can be from about 1 V to about 200 V, or from about 100 mv to about 5000 mv, or from about 0.1 mV to about 100 mV.

[0066] The second feedback circuit 340 may include a transistor 345, which may include a source 345a, a gate 345b, and a drain 345c. The transistor 345 is operable to receive a current i1 345i, which may be the same current as the current i1 343i at a different location in the voltage regulator circuit 300. The second feedback circuit 340 may include a transistor 346 (which may be an n-channel transistor), which may include a source 345a, a gate 345b, and a drain 345c. The transistor 346 may be connected to a transistor 346 (which may be an n-channel transistor), which may include a source 346a, a gate 346b, and a drain 346c. The transistors 345 and 346 may be connected to a transistor 347 (which may be an n-channel transistor), which may include a source 347a, a gate 347b, and a drain 347c.

[0067] In another example, the voltage regulator circuit 300 may include an output node 312, a regulating transistor 310, one or more of a first feedback circuit 330a, 330b, or a second feedback circuit 340. The output node 312 is operable to connect to a load 320. The regulating transistor 310 is operable to transfer current to the output node 312 based on a voltage 342 applied to the regulating transistor 310. The regulating transistor 310 may be a p-channel transistor. The first feedback circuits 330a, 330b are operable to regulate the voltage 342 applied to the regulating transistor 310 based on the voltage at the output node 312. The second feedback circuit 340 may be configured to reduce the impedance of the output node 312. The voltage regulator circuit may further include a circuit (e.g., Figure 1 circuit 150 in Figure 2 circuit 250 in Figure 4 circuit 450 in

[0068] ), which may be used to increase the phase margin of the voltage regulator circuit 300. In some examples, the second feedback circuit 340 may include an alternating current (AC) feedback loop.

[0069] The voltage regulator circuit 300 may be modified, added to, or omitted without departing from the scope of the present disclosure.

[0070] As Figure 4As shown, the voltage regulator may include an output node 412, a regulating transistor 410, first feedback circuits 430a, 430b, a second feedback circuit 440, or one or more of the circuits. The output node 412 may be operable to connect to a load 420. The regulating transistor 410 may be operable to transfer current to the output node 412 based on a voltage 442 applied to the regulating transistor 410. The regulating transistor may be a p-channel transistor. The first feedback circuits 430a, 430b may be operable to regulate the voltage 442 applied to the regulating transistor based on the voltage of the output node 412. The voltage 442 applied to the regulating transistor 410 may be from about 1V to about 200V, or from about 100mv to about 5000mv, or from about 0.1mV to about 100mV. The second feedback circuit 440 may be operable to regulate the voltage 442 applied to the regulating transistor 410 based on a change in the voltage of the output node 412. The change in the voltage of the output node 412 may be any suitable amount less than or equal to the voltage of the regulating transistor 410. The change in the voltage of the output node 412 may be from about 1V to about 200V, or from about 100mv to about 5000mv, or from about 0.1mV to about 100mV, or from 1μV to about 1000μV.

[0071] The regulating transistor 410 may be with respect to Figure 2 and Figure 3 the disclosed configuration. The regulating transistor 410 may include a transistor 408 (e.g., a p-channel transistor) that includes one or more of a source 408a, a gate 408b, or a drain 408c.

[0072] The load 420 may be with respect to Figure 2 the disclosed configuration. The load 420 may include one or more of a resistor 422 or a capacitor 424.

[0073] The first feedback circuits 430a, 430b may be with respect to Figures 2 - 4 the disclosed configuration. The voltage divider may include resistors 438a and 438b that may be operable to output a voltage feedback 434b that may be directed to the positive terminal 434a of an amplifier 433. The amplifier may receive a voltage at a negative terminal 432. The voltage may be from about 1V to about 200V, or from about 100mv to about 5000mv, or from about 0.1mV to about 100mV. The amplifier may be connected to a connection 436 of a circuit 450 or a capacitor 435.

[0074] The second feedback circuit 440 may be with respect to Figure 2 and Figure 3The disclosed configuration. The second feedback circuit 440 may include one or more of the following: one or more transistors 443, 445, 446, 447. Transistor 443 may be a p-channel transistor including a source 443a, a gate 443b, and a drain 443c. Transistor 445 may be an n-channel transistor including a source 445a, a gate 445b, and a drain 445c. Transistor 446 may be an n-channel transistor including a source 446a, a gate 446b, and a drain 446c. Transistor 447 may be an n-channel transistor including a source 447a, a gate 447b, and a drain 447c. The second feedback circuit may include a resistor 444.

[0075] The circuit 450 may include one or more transistors 455, 456, 457, 459 in a mirror configuration (e.g., transistors 455 and 456 may be in a mirror configuration, and transistors 457 and 459 may be in a mirror configuration) to facilitate one or more of the following: improving the transient response of the voltage regulator circuit 400, or making the increased power supply rejection ratio (PSRR) of the voltage regulator circuit 400 match the PSRR when an n-channel transistor is used at the adjustment transistor 410.

[0076] Transistor 455 may be a p-channel transistor having a source 455a, a gate 455b, and a drain 455c. Transistor 455 may be a mirror of transistor 456. Transistor 456 may be a p-channel transistor having a source 456a, a gate 456b, and a drain 456c. The drain 456c may be connected to the gates 456b and 455b using a connection 457a.

[0077] Transistor 458 may be an n-channel transistor having a source 458a, a gate 458b, and a drain 458c. Transistor 458 may include a connection 457b between the source 458a and the gate 458b. Transistor 458 may be a mirror of transistor 459. Transistor 459 may be an n-channel transistor having a source 459a, a gate 459b, and a drain 459c.

[0078] The voltage regulator circuit 400 can be similar to the voltage regulator circuit 200, except that the circuit 450 of the voltage regulator circuit 400 can be different from the circuit 250 of the voltage regulator circuit 200. In these and other examples, the circuit 450 can include four transistors (e.g., 455, 456, 457, 459). The one or more transistors 455, 456 (e.g., p-channel metal oxide semiconductor (PMOS) transistors) can be connected to VDDA_PD, and the two n-channel transistors 457, 459 (e.g., NMOS transistors) can be connected to ground. The circuit 450 can adjust the configuration of the voltage regulator circuit 400 to increase the PSRR bandwidth and transient response of the voltage regulator circuit 400. For example, the PSRR bandwidth can be increased based on the circuit 450, which helps reduce the impedance between the second feedback circuit 440 and the gate 408b of the regulating transistor 410. As another example, due to the action of the circuit 450, the second feedback circuit 440 can obtain more current from the regulating transistor 410, thereby improving the transient response.

[0079] In another example, the voltage regulator circuit 400 can include an output node 412, a regulating transistor 410, first feedback circuits 430a, 430b, a second feedback circuit 440, or one or more of the circuits. The output node 412 can be operable to connect to a load 420. The regulating transistor 410 can be operable to transfer current to the output node 412 based on a voltage 442 applied to the regulating transistor 410, where the regulating transistor 410 includes a regulating transistor p-channel transistor. The first feedback circuits 430a, 430b can be operable to regulate the voltage 442 output to the regulating transistor based on the voltage of the output node 412. The second feedback circuit 440 can include a second feedback circuit first n-channel transistor (e.g., transistor 445) and a second feedback circuit second n-channel transistor (e.g., transistor 446). The circuit 450 can include one or more circuit transistors (e.g., transistors 455, 456, 457, 459) in a mirror configuration to increase one or more of the power supply rejection ratio (PSRR) bandwidth or transient response of the voltage regulator. In some examples, compared with the circuit 250, using the circuit 450 can improve the transient response and PSRR bandwidth. In these and other examples, the improvement can be more than one order of magnitude. In one example, for a bandwidth from 10 Hz to about 10 megahertz (MHz), the power supply rejection ratio can be from -100 dB to about -3 dB, or from about -80 dB to about -10 dB, or from about -50 dB to about -10 dB. In one example, the transient response of the voltage regulator can be from 1 μs to about 100 μs, or from 100 ns to about 10 μs, or from 0.1 ns to about 100 ns.

[0080] The circuit 450 can be a dynamic system that can mirror a portion of the load 420 current, thereby increasing the current in the second feedback circuit 440. This portion of the load 420 current can be a ratio of the load 420 current. In this way, the current in the second feedback circuit 440 can vary proportionally with the variation of the load 420 current.

[0081] The transistor 456 can be in a mirror configuration with the transistor 455 and can be designed to provide a portion of the current provided by the transistor 408. This mirror configuration can be based on the configuration of the transistors 455, 456, 457, 459 in the circuit 450 as Figure 4 shown.

[0082] The one or more circuit transistors (e.g., transistors 455, 456, 457, 459) can include one or more circuit p-channel transistors (e.g., transistors 455, 456) and one or more circuit n-channel transistors (e.g., transistors 458, 459). The one or more circuit transistors (e.g., transistors 455, 456, 457, 459) can include a circuit first p-channel transistor (e.g., transistor 456) and a circuit first mirror p-channel transistor (e.g., transistor 455), and the circuit first p-channel transistor and the circuit first mirror p-channel transistor can be operable to input current (or source current) to one or more regulating p-channel transistors (e.g., transistor 408 of regulator 410) or a second feedback circuit first n-channel transistor (e.g., transistor 445). The one or more circuit transistors (e.g., transistors 455, 456, 457, 459) can include a circuit first n-channel transistor (e.g., transistor 459) and a circuit first mirror n-channel transistor (e.g., transistor 458), and the circuit first n-channel transistor and the circuit first mirror n-channel transistor can be operable to receive current from a second feedback circuit first n-channel transistor (e.g., transistor 445 of the second feedback circuit 440).

[0083] This dual-mirror configuration of the one or more transistors (e.g., transistors 455, 456, 457, 459) can be used to regulate an input current or receive an output current from other components of the voltage regulator circuit 400. The one or more transistors (e.g., transistors 455, 456, 457, 459) can include a first p-channel transistor of the circuit (e.g., transistor 456) that is used to regulate the input current to a second n-channel transistor of the second feedback circuit (e.g., transistor 446). The one or more transistors (e.g., transistors 455, 456, 457, 459) can include a first n-channel transistor of the circuit (e.g., transistor 459) that is used to regulate the output current from the second n-channel transistor of the second feedback circuit (e.g., transistor 446), and the ratio of the output current (e.g., from transistor 446 to transistor 459) to the input current (e.g., from transistor 456 to transistor 446) can be greater than one or more of the following: 1.0, 1.2, 1.5, 1.8, 2.0, or the like. The ratio of the output current to the input current can be selected to regulate the current from the regulating p-channel transistor (e.g., transistor 408) to the second n-channel transistor of the second feedback circuit (e.g., transistor 446). The output current can be from about 1 A to about 100 A, or from about 100 μA to about 5000 mA, or from about 1 μA to about 1000 mA. The input current can be from about 0.5 A to about 50 A, or from about 50 μA to about 2500 mA, or from about 0.5 μA to about 500 mA.

[0084] For example, transistor 456 can provide 1 / 100 or less of the current provided by transistor 408. Based on the configuration of transistor 456, transistor 456 can provide less current. In some examples, when transistor 408 provides current, transistor 456 can provide current, and when transistor 408 does not provide current, transistor 456 can not provide current. Transistor 455 can be in a mirror image relationship with transistor 456.

[0085] In some examples, the current provided by transistor 456 can pass through 445. The source current amount can be the i-track-p current. The i-track-p current can be the ratio of the current provided by transistor 408. Transistor 459 can absorb at least twice the current compared to the current provided by transistor 456. Transistor 459 can be mirrored by transistor 457. Based on the configurations of transistor 459 and transistor 456, transistor 459 can absorb more current than the current provided by transistor 456. Because transistor 459 can absorb more current than transistor 456 can provide, this difference in absorption and provision can cause transistor 446 to draw more current from transistor 408. For example, this difference in absorption and provision can cause transistor 446 to provide more current, and this more current is equal to the difference between the current provided by transistor 456 and the current absorbed by transistor 459.

[0086] The current generated by transistor 456 and absorbed by transistor 459 can be a dynamic current, such as an AC transient current. Therefore, the currents generated and absorbed by transistors 456 and 459 can contribute to the transient change of the load current. The first feedback circuits 430a and 430b and the second feedback circuit 440 can help promote a static direct current (DC) that can maintain the voltage at output node 412. The voltage at output node 412 can be from about 1V to about 200V, or from about 100 mV to about 5000 mV, or from about 0.1 mV to about 100 mV.

[0087] The voltage regulator circuit can have a dynamic current and a static current. The dynamic current can include currents 413i, 445i, 455i, 456i, 458i, 459i, and the static DC current can include currents 443i, 456i, 447i, and 434i. Currents 413i and 445i can be the dynamic currents from transistors 445 and 446 respectively. Current 445i can be the dynamic current from transistor 445. Currents 455i, 456i, 458i, and 459i can be the dynamic currents across transistors 455, 456, 457, 459 respectively. The static current can include currents 434i, 443i, 444i, 447i. Currents 443i and 447i can be the static DC currents across transistors 443 and 447 respectively. Current 434i can be the static DC current between resistors 438a and 438b. Current 444i can be the static DC current across resistor 444.

[0088] Without departing from the scope of the present disclosure, the voltage regulator circuit 400 can be modified, added to, or omitted. The voltage regulator circuit 400 can use reference Figure 2 and / or Figure 3configured by the described voltage, resistance, capacitance, conductance, current, etc.

[0089] In another example, the voltage regulator circuit 400 may include a voltage regulator, which may include an output node 412, an adjustment transistor 410, first feedback circuits 430a, 430b, a second feedback circuit 440, or one or more of the circuits. The output node 412 may be operable to connect to a load 420. The adjustment transistor 410 may be operable to transfer current to the output node 412 based on a voltage 442 applied to the adjustment transistor 410. The adjustment transistor 410 may include a p-channel transistor. The first feedback circuits 430a, 430b may be operable to regulate the voltage 442 output to the adjustment transistor based on the voltage of the output node 412. The second feedback circuit 440 may be configured to reduce the impedance of the output node 412. The circuit 450 may be operable to increase the phase margin of the voltage regulator circuit 400. The first feedback circuit may include one or more of a first resistor, a second resistor, or an amplifier. The circuit may include one or more transistors in a mirror configuration (e.g., transistors 455 and 456, or transistors 457 and 459).

[0090] In Figure 2 , Figure 3 and Figure 4 shown, the transistors are shown in the form of metal-oxide-semiconductor field-effect transistors (MOSFETs) and bipolar junction transistors (BJTs). The above description uses the terms "gate, source, and drain" to denote different terminals of a transistor. The use of the names "gate, source, and drain" can be used to generally describe the terminals of MOSFET transistors, BJT transistors, or other types of transistors (e.g., junction gate field-effect transistors (JFETs) and insulated-gate bipolar transistors). Additionally, a p-channel transistor or some combination of n-channel and p-channel transistors can also be used instead of Figure 2 , Figure 3 and Figure 4 the transistors shown in

[0091] Figure 5 illustrates a process flow of an example method 500 for a voltage regulator circuit according to at least one example described in the present disclosure. The method 500 may be arranged according to at least one example described in the present disclosure.

[0092] The method 500 may be executed by processing logic including hardware (circuits, dedicated logic, etc.), software (e.g., software running on a computer system or a dedicated machine), or a combination of both, where the processing logic may be included in Figure 8 a processing device (e.g., a processor 802) or another device, a combination of devices, or a system.

[0093] Method 500 may begin at block 505, where the processing logic may transfer current to an output node based on a voltage applied to an adjustment transistor.

[0094] At block 510, the processing logic may adjust the voltage applied to the adjustment transistor based on the output node voltage.

[0095] At block 515, the processing logic may adjust the voltage applied to the adjustment transistor based on a change in the output node voltage.

[0096] Modifications, additions, or omissions may be made to method 500 without departing from the scope of the present disclosure. For example, in some examples, method 500 may include any number of additional components that may not be explicitly shown or described.

[0097] Figure 6 A process flow of an example method 600 that may be used in a voltage regulator circuit in accordance with at least one example described in the present disclosure is shown. Method 600 may be arranged in accordance with at least one example described in the present disclosure.

[0098] Method 600 may be performed by processing logic that includes hardware (circuits, dedicated logic, etc.), software (e.g., software running on a computer system or a dedicated machine), or a combination of both, which may be included in Figure 8 a processing device (e.g., processor 802) or another device, combination of devices, or system.

[0099] At block 605, the processing logic may transfer current to an output node based on a voltage applied to an adjustment transistor.

[0100] At block 610, the processing logic may adjust the voltage applied to the adjustment transistor based on the output node voltage.

[0101] At block 615, the processing logic may reduce the impedance of the output node.

[0102] At block 620, the processing logic may increase the phase margin of the voltage regulator circuit.

[0103] Modifications, additions, or omissions may be made to method 600 without departing from the scope of the present disclosure. For example, in some examples, method 600 may include any number of additional components that may not be explicitly shown or described.

[0104] Figure 7 A process flow of an example method 700 that may be used in a voltage regulator circuit in accordance with at least one example described in the present disclosure is shown. Method 700 may be arranged in accordance with at least one example described in the present disclosure.

[0105] Method 700 may be performed by processing logic that includes hardware (circuitry, dedicated logic, etc.), software (e.g., software running on a computer system or a dedicated machine), or a combination of both, which may be included in Figure 8 a processing device (e.g., processor 802) or another device, device combination, or system.

[0106] Method 700 may begin at block 705, where the processing logic may transfer current to an output node based on a voltage applied to an adjustment transistor.

[0107] At block 710, the processing logic may adjust the voltage output to the adjustment transistor based on the output node voltage.

[0108] At block 715, the processing logic may use one or more circuit transistors in a mirror configuration to increase one or more of the power supply rejection ratio (PSRR) bandwidth or transient response of a voltage regulator circuit.

[0109] Modifications, additions, or omissions may be made to method 700 without departing from the scope of the present disclosure. For example, in some examples, method 700 may include any number of additional components that may not be explicitly shown or described.

[0110] For simplicity of explanation, the methods and / or process flows described herein are depicted and described as a series of acts. However, acts in accordance with the present disclosure may occur in various orders and / or concurrently, and may occur with other acts not presented and described herein. Additionally, not all acts shown may be used to implement the methods in accordance with the disclosed subject matter. Further, those skilled in the art will understand and appreciate that these methods may alternatively be represented as a series of related states via a state diagram or events. Additionally, the methods disclosed in this specification are capable of being stored on an article of manufacture such as a non-transitory computer-readable medium to facilitate the transfer and conveyance of these methods to a computing device. The term "article of manufacture" as used herein is intended to encompass a computer program accessible from any computer-readable device or storage medium. Although depicted as discrete blocks, various blocks may, according to the desired implementation, be divided into additional blocks, combined into fewer blocks, or eliminated.

[0111] Certain portions of the detailed description are presented in terms of algorithms and symbolic representations of operations within a computer. An algorithm may be a series of configured operations leading to a desired final state or result. In an example implementation, the operations performed may be realized by the manipulation of physical quantities of an entity to effect a result that is tangible.

[0112] Descriptions using terms such as detecting, determining, analyzing, identifying, scanning, etc. can include actions and processes of a computer system or other information processing device that can manipulate and / or transform data represented as a physical (electronic) quantity within the registers and memories of the computer system into other data similarly represented as a physical quantity within the memories or registers of the computer system or other information storage, transmission, or display devices.

[0113] Example implementations can also relate to apparatuses for performing the operations herein. The apparatus can be specially constructed for the operations provided herein, or it can include one or more general-purpose computers selectively activated or reconfigured by one or more computer programs. Such computer programs can be stored in a computer-readable medium (e.g., a computer-readable storage medium or a computer-readable signal medium). Computer-executable instructions can include, for example, instructions and data that cause a general-purpose computer, a special-purpose computer, or a special-purpose processing device (e.g., one or more processors) to perform or control the performance of a certain function or group of functions.

[0114] Figure 8 A diagram of an example form of a machine, a computing device 800, is shown in which a set of instructions can be executed to cause the machine to perform any one or more of the methods discussed herein. The computing system can be used to implement or direct one or more operations associated with latency-based contention. The computing device 800 can include a rack server, a router computer, a server computer, a mainframe computer, a laptop computer, a tablet computer, a desktop computer, or any computing device having at least one processor in which a set of instructions can be executed to cause the machine to perform any one or more of the methods discussed herein. In an alternative example, the machine can be connected (e.g., networked) to other machines in a local area network (LAN), an intranet, an extranet, or the Internet. The machine can operate in the capacity of a server machine in a client-server network environment. Further, although only a single machine is shown, the term "machine" can also include any collection of machines that individually or jointly execute a set (or multiple sets) of instructions to perform any one or more of the methods discussed herein.

[0115] The example computing device 800 includes a processing device (e.g., a processor 802), a main memory 804 (e.g., a read-only memory (ROM), a flash memory, a dynamic random access memory (DRAM) such as synchronous DRAM (SDRAM)), a static memory 806 (e.g., a flash memory, a static random access memory (SRAM)), and a data storage device 816, which communicate via a bus 808.

[0116] The processing device (e.g., processor 802) represents one or more general-purpose processing devices, such as a microprocessor, a central processing unit, etc. More specifically, the processing device (e.g., processor 802) may include a complex instruction set computing (CISC) microprocessor, a reduced instruction set computing (RISC) microprocessor, a very long instruction word (VLIW) microprocessor, or a processor implementing other instruction sets or an instruction set combination. The processing device (processor 802) may also include one or more dedicated processing devices, such as an application specific integrated circuit (ASIC), a field programmable gate array (FPGA), a digital signal processor (DSP), a network processor, etc. The processing device (e.g., processor 802) is configured to execute the instructions 826 for performing the operations and steps discussed herein.

[0117] The computing device 800 may also include a network interface device 822 that can communicate with the network 818. The computing device 800 may also include a display device 810 (e.g., a liquid crystal display (LCD) or a cathode ray tube (CRT)), an alphanumeric input device 812 (e.g., a keyboard), a cursor control device 814 (e.g., a mouse), and a signal generation device 820 (e.g., a speaker). In at least one example, the display device 810, the alphanumeric input device 812, and the cursor control device 814 may be combined into a single component or device (e.g., an LCD touch screen).

[0118] The data storage device 816 may include a computer-readable storage medium 824 on which a set or multiple sets of instructions 826 are stored, and the set or multiple sets of instructions 826 embody any one or more of the methods or functions described herein. During the execution of the instructions 826 by the computing device 800, the instructions 826 may also reside completely or at least partially within the main memory 804 and / or the processing device (e.g., processor 802), and the main memory 804 and the processing device (e.g., processor 802) also constitute computer-readable media. These instructions may also be sent or received over the network 818 via the network interface device 822.

[0119] Although the computer-readable storage medium 824 is shown as a single medium in the example, the term "computer-readable storage medium" may include a single medium or multiple media (e.g., a centralized or distributed database and / or associated caches and servers) that store a set or multiple sets of instructions. The term "computer-readable storage medium" may also include any medium that is capable of storing, encoding, or carrying a set of instructions executable by a machine and causing the machine to perform any one or more of the methods of the present disclosure. Thus, the term "computer-readable storage medium" may include, but is not limited to, solid-state memory, optical media, and magnetic media.

[0120] In some examples, the different components, modules, engines, and services described herein can be implemented as objects or processes executing on a computing system (e.g., as separate threads). While some of the systems and methods described herein are generally described as being implemented in software (stored on and / or executed by hardware), specific hardware implementations or implementations of a combination of software and specific hardware are also possible and contemplated.

[0121] Unless the specific arrangements described herein are mutually exclusive, the various embodiments described herein can be combined, in whole or in part, to enhance system functionality and / or to produce complementary functionality. Similarly, aspects of the implementations can be implemented in separate arrangements. Accordingly, the foregoing description is given by way of example only, and details may be modified within the scope of the present invention.

[0122] The terms used herein (especially the terms used in the appended claims, e.g., the body of the appended claims) are generally intended to be "open" terms. For example, the term "comprising" should be interpreted as "comprising, but not limited to", the term "having" should be interpreted as "having at least", the term "including" should be interpreted as "including, but not limited to", and so on.

[0123] Furthermore, if an intention is to introduce a specific number of claim limitations, such intention will be explicitly recited in the claims, and if there is no such intention, there is no such intention. For example, for purposes of aiding understanding, the appended claims may contain introductory phrases "at least one" and "one or more" to introduce claim limitations. However, even when the same claim includes an introductory phrase "one or more" or "at least one" and an indefinite article such as "a" or "an" (e.g., "a" and / or "an" should be interpreted as meaning "at least one" or "one or more"), the use of such phrases should not be construed as implying that any particular claim that includes such introduced claim limitation is limited to an embodiment containing only one such limitation. The same holds for the use of definite articles used to introduce claim limitations.

[0124] In addition, even if the specific number of the technical features introduced in the claims is clearly recited, those skilled in the art will also recognize that such technical features should be construed to mean at least that number of the technical features (e.g., a simple recitation of "two technical features" without any other modifiers means at least two of such technical features, or two or more of such technical features). In addition, in cases where expressions similar to "at least one of A, B, and C" or "one or more of A, B, and C" are used, generally, such constructions are intended to include A alone, B alone, C alone, A and B together, A and C together, B and C together, or A, B, and C together, and so on. For example, the use of the term "and / or" is intended to be construed in this manner.

[0125] In addition, whether in the specification, claims, or drawings, any disjunctive word or phrase preceding two or more alternative terms should be understood to contemplate the possibility of including one of the terms, another of the terms, or both of the terms. For example, the phrase "A or B" should be understood to include the possibility of "A" or "B" or "A and B".

[0126] In addition, the use of the terms "first", "second", "third", etc. herein does not necessarily imply a particular order or number of elements. Generally, the terms "first", "second", "third", etc. are used to distinguish different elements as general identifiers. Without stating that the words "first", "second", "third", etc. mean a particular order, these words should not be understood to imply a particular order. In addition, without stating that the terms "first", "second", "third", etc. mean a particular number of elements, these terms should not be understood to imply a particular number of elements. For example, a first component may be described as having a first side, and a second component may be described as having a second side. The use of the term "second side" with respect to the second component may be to distinguish this side of the second component from the "first side" of the first component, rather than to imply that the second component has two sides.

[0127] All examples and conditional language cited in this disclosure are for illustrative purposes only, to assist the reader in understanding the disclosure and the concepts contributed by the inventors to advance the art, and should be understood as not being limited to these specifically cited examples and conditions. Although the embodiments of the disclosure have been described in detail, it should be understood that various changes, substitutions, and alterations can be made without departing from the spirit and scope of the disclosure.

Claims

1. A voltage regulator, comprising: An output node operable to be connected to a load; An adjustment transistor operable to transfer current to the output node based on a voltage applied to the adjustment transistor, wherein the adjustment transistor includes a p-channel transistor; A first feedback circuit operable to regulate the voltage applied to the adjustment transistor based on the output node voltage; and A second feedback circuit operable to regulate the voltage applied to the adjustment transistor based on a change in the output node voltage.

2. The voltage regulator according to claim 1, wherein, The first feedback circuit includes a first resistor, a second resistor, and an amplifier, and wherein the first feedback circuit is operable to generate a voltage feedback to be input to the amplifier by using the first resistor and the second resistor.

3. The voltage regulator according to claim 1, wherein, The second feedback circuit is operable to promote a reduced impedance at the output node by using a voltage follower.

4. The voltage regulator according to claim 1, wherein, The second feedback circuit is operable to promote the main pole of the voltage regulator, and the main pole has increased stability in response to a load change.

5. The voltage regulator according to claim 1, wherein, The second feedback circuit is operable to adjust the output node based on the output voltage from the first feedback circuit and the change in the output node voltage.

6. The voltage regulator according to claim 1, wherein, The second feedback circuit includes an alternating current (AC) feedback loop that promotes dynamic current to increase the transient response of the voltage regulator.

7. The voltage regulator according to claim 1, further comprising a circuit including: One or more of a capacitor or a resistor, wherein the circuit is operable to increase the phase margin of the voltage regulator based on one or more of the main pole of the voltage regulator or the zero point of the voltage regulator.

8. The voltage regulator according to claim 1, further comprising a circuit including one or more transistors in a mirror configuration to facilitate one or more of the following: Improving the transient response of the voltage regulator, or Making the increased power supply rejection ratio (PSRR) of the voltage regulator match the PSRR when an n-channel transistor is used at the adjustment transistor.

9. A voltage regulator, comprising: An output node operable to be connected to a load; An adjustment transistor operable to transfer current to the output node based on a voltage applied to the adjustment transistor, wherein the adjustment transistor includes a p-channel transistor; A first feedback circuit operable to regulate the voltage applied to the adjustment transistor based on the output node voltage; A second feedback circuit operable to reduce the impedance of the output node; and A circuit operable to increase the phase margin of the voltage regulator.

10. The voltage regulator according to claim 9, wherein, The first feedback circuit includes a first resistor, a second resistor, and an amplifier.

11. The voltage regulator according to claim 9, wherein, The second feedback circuit includes a voltage follower.

12. The voltage regulator according to claim 9, wherein, The second feedback circuit includes an alternating current (AC) feedback loop.

13. The voltage regulator according to claim 9, wherein, The circuit includes one or more of a capacitor or a resistor.

14. The voltage regulator according to claim 9, wherein, The circuit includes one or more transistors in a mirror configuration.

15. A voltage regulator, comprising: An output node operable to be connected to a load; A regulating transistor, the regulating transistor being configured to transfer current to the output node based on a voltage applied to the regulating transistor, wherein the regulating transistor includes a p-channel transistor; and A first feedback circuit, the first feedback circuit being operable to regulate the voltage output to the regulating transistor based on the output node voltage; A second feedback circuit, the second feedback circuit including a first n-channel transistor of the second feedback circuit and a second n-channel transistor of the second feedback circuit; and A circuit including one or more circuit transistors, the one or more circuit transistors being in a mirror configuration to increase one or more of the power supply rejection ratio (PSRR) bandwidth or transient response of the voltage regulator.

16. The voltage regulator according to claim 15, wherein, The one or more circuit transistors include one or more p-channel circuit transistors and one or more n-channel circuit transistors.

17. The voltage regulator according to claim 15, wherein, The one or more circuit transistors include a first p-channel circuit transistor and a first mirror p-channel circuit transistor, the first p-channel circuit transistor and the first mirror p-channel circuit transistor being operable to input current to one or more of the p-channel regulating transistor or the first n-channel transistor of the second feedback circuit.

18. The voltage regulator according to claim 15, wherein, The one or more circuit transistors include a first n-channel circuit transistor and a first mirror n-channel circuit transistor, the first n-channel circuit transistor and the first mirror n-channel circuit transistor being operable to receive current from the first n-channel transistor of the second feedback circuit.

19. The voltage regulator according to claim 15, wherein The one or more circuit transistors include: A first p-channel circuit transistor, the first p-channel circuit transistor being operable to regulate the input current to the second n-channel transistor of the second feedback circuit, and A first n-channel circuit transistor, the first n-channel circuit transistor being operable to regulate the output current from the second n-channel transistor of the second feedback circuit, wherein the ratio of the output current to the input current is greater than 1.

0.

20. The voltage regulator according to claim 19, wherein, The ratio of the output current to the input current is selected to regulate current from the p-channel regulating transistor to the second n-channel transistor of the second feedback circuit.

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