CN217238691U - Low dropout regulator, low power consumption power supply circuit and electronic equipment - Google Patents
Low dropout regulator, low power consumption power supply circuit and electronic equipment Download PDFInfo
- Publication number
- CN217238691U CN217238691U CN202123440869.2U CN202123440869U CN217238691U CN 217238691 U CN217238691 U CN 217238691U CN 202123440869 U CN202123440869 U CN 202123440869U CN 217238691 U CN217238691 U CN 217238691U
- Authority
- CN
- China
- Prior art keywords
- resistor
- low dropout
- switch
- capacitor
- power
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Landscapes
- Continuous-Control Power Sources That Use Transistors (AREA)
Abstract
The utility model provides a low dropout regulator, low-power consumption supply circuit and electronic equipment, include: the power switch tube, the feedback unit and the error amplifier; the first end of the power switch tube is connected with a power supply voltage, and the second end of the power switch tube is grounded through the feedback unit; the power supply is output by the connection node of the power switch tube and the feedback unit; the error amplifier receives the feedback voltage output by the feedback unit and a reference voltage, amplifies the difference between the feedback voltage and the reference voltage and outputs the amplified difference to the control end of the power switch tube; the feedback unit samples and feeds back the voltage of the second end of the power switch tube to the error amplifier when the low dropout regulator works, and the charge loss on the first capacitor is reduced when the low dropout regulator stops working. The utility model discloses a reduce the discharge current of the external electric capacity of LDO or keep the back with the electric charge that the external electric capacity of LDO was released and supply for external electric capacity, consumption when greatly reduced LDO starts with long time spending, improve LDO's stability.
Description
Technical Field
The utility model relates to an integrated circuit field especially relates to a low dropout regulator, low-power consumption supply circuit and electronic equipment.
Background
A low dropout regulator (LDO) is a module capable of providing stable power, and generally has very low self-noise and high power Supply Rejection ratio (psrr), and is widely used in integrated circuit design.
The power consumption and time duration overhead of the conventional low dropout linear regulator during starting are generally large, and how to reduce the extra power consumption overhead of charging an external capacitor during the periodic work of an LDO becomes one of the problems to be solved by the technical staff in the field.
SUMMERY OF THE UTILITY MODEL
In view of the above shortcomings in the prior art, an object of the present invention is to provide a low dropout regulator, a low power supply circuit and an electronic device, which are used to solve the problem of large power consumption and time-consuming overhead when the low dropout regulator in the prior art is started.
To achieve the above and other related objects, the present invention provides a low dropout regulator, having an output connected with a first capacitor in parallel, the low dropout regulator including at least:
the power switch tube, the feedback unit and the error amplifier; the first end of the power switch tube is connected with a power supply voltage, and the second end of the power switch tube is grounded through the feedback unit; a power supply is output from a connection node of the power switch tube and the feedback unit; the error amplifier receives the feedback voltage output by the feedback unit and a reference voltage, amplifies the difference between the feedback voltage and the reference voltage and outputs the amplified difference to the control end of the power switch tube;
the feedback unit samples and feeds back the voltage of the second end of the power switch tube to the error amplifier when the low dropout regulator works, and the charge loss on the first capacitor is reduced when the low dropout regulator stops working.
Optionally, the feedback unit includes a first resistor, a second resistor, a third resistor connected in series to the second end of the power switch tube in sequence, and a first switch connected in parallel to two ends of the third resistor; the first switch receives a control signal; the feedback voltage is output between the first resistor and the second resistor.
More optionally, a resistance value of the third resistor is greater than a sum of resistance values of the first resistor and the second resistor.
More optionally, the third resistor has a resistance greater than 10 megohms.
More optionally, the third resistor has a resistance value set to 2 megohm to 10 megohm.
Optionally, the feedback unit includes a first resistor, a second capacitor connected in series to the second end of the power switch tube in sequence, and a first switch connected in parallel to two ends of the second capacitor; the first switch receives a control signal; the feedback voltage is output between the first resistor and the second resistor.
More optionally, the second resistor is an adjustable resistor.
More optionally, the feedback unit further includes a third capacitor, and the third capacitor is connected in parallel to two ends of the first resistor.
More optionally, the low dropout regulator further includes a second switch, one end of the second switch is connected to the power supply voltage, the other end of the second switch is connected to the control end of the power switch tube, and the second switch receives an enable signal.
To achieve the above and other related objects, the present invention provides a low power supply circuit, which comprises at least:
n gating switches, a logic control module and the low dropout linear regulator;
the logic control module is used for generating an enabling signal, a control signal and n gating signals; the enabling signal is used for starting the low dropout linear regulator to work, the control signal is used for controlling the working state of the first switch, and the gating signal is used for gating a power supply path of a corresponding power utilization circuit;
the input end of each gating switch is connected with the output end of the low dropout linear regulator, and each gating switch receives a corresponding gating signal;
wherein n is a natural number of 1 or more.
To achieve the above and other related objects, the present invention provides an electronic device, comprising:
the power supply circuit comprises a first capacitor, m power utilization circuits and the low-power-consumption power supply circuit;
the upper polar plate of the first capacitor is connected with the output end of the low-voltage-difference linear voltage stabilizer in the low-power-consumption power supply circuit, and the lower polar plate is grounded;
each circuit is respectively connected with the output end of the corresponding gating switch, and acquires a power supply based on the corresponding gating signal;
wherein m is a natural number of 1 or more.
Optionally, the power utilization circuit is a pressure sensor.
As described above, the utility model discloses a low dropout regulator, low-power consumption supply circuit and electronic equipment has following beneficial effect:
the utility model discloses a low dropout regulator, low-power consumption supply circuit and electronic equipment supply for external electric capacity through the discharge current that reduces the external electric capacity of LDO or keep the back with the electric charge that the external electric capacity of LDO was released, consumption when greatly reduced LDO starts with long time spending, improve the stability of LDO.
Drawings
Fig. 1 is a schematic diagram of a low dropout regulator according to the present invention.
Fig. 2 is a schematic diagram illustrating the operation of the low dropout regulator according to the first embodiment.
Fig. 3 is a schematic diagram of another low dropout regulator according to the present invention.
Fig. 4 is a schematic diagram illustrating the operation of the low dropout regulator according to the second embodiment.
Fig. 5 is a schematic structural diagram of the low power consumption power supply circuit of the present invention.
Fig. 6 is a schematic structural diagram of the electronic device according to the present invention.
Description of the element reference numerals
1 low dropout regulator
11 feedback unit
12 error amplifier
2 logic control module
Detailed Description
The following description of the embodiments of the present invention is provided for illustrative purposes, and other advantages and effects of the present invention will be readily apparent to those skilled in the art from the disclosure herein. The present invention can also be implemented or applied through other different specific embodiments, and various details in the present specification can be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention.
Please refer to fig. 1 to 6. It should be noted that the drawings provided in the present embodiment are only for illustrating the basic idea of the invention in a schematic manner, and only the components related to the invention are shown in the drawings rather than being drawn according to the number, shape and size of the components in actual implementation, and the form, quantity and proportion of the components in actual implementation may be changed at will, and the layout of the components may be more complicated.
Example one
As shown in fig. 1, the present embodiment provides a low dropout regulator 1, an output terminal of which is connected in parallel with a first capacitor C1, wherein the low dropout regulator 1 includes:
power switch M1, feedback unit 11, and error amplifier 12.
As shown in fig. 1, a first end of the power switch M1 is connected to a power supply voltage VDD, a second end is grounded via the feedback unit 11, a control end is connected to the output end of the error amplifier 12, and a connection node between the power switch M1 and the feedback unit 11 outputs a power supply VLDO; the power switch tube M1 is used for adjusting the current flowing through the power switch tube M1.
Specifically, in this embodiment, the source of the power switch M1 is connected to the power supply voltage VDD, the drain is connected to the feedback unit 11, and the gate is connected to the output terminal of the error amplifier 12. In practical use, the types of the devices of the power switch tube are not limited, and include but not limited to an insulated gate bipolar transistor and a metal-oxide semiconductor field effect transistor, and any device capable of adjusting the current flowing through the power switch tube based on the output signal of the error amplifier 12 is suitable for use, which is not described herein again.
Specifically, as another implementation manner of the present invention, the low dropout regulator 1 further includes a second switch SW2, one end of the second switch SW2 is connected to the power supply voltage VDD, and the other end is connected to the control end of the power switch tube M1; the second switch SW2 receives the enable signal EN _ LDO. When the enable signal EN _ LDO is effective, starting the low dropout linear regulator 1 to work; when the enable signal EN _ LDO is not active, the LDO1 stops working. As an example, the second switch SW2 is implemented by using an NMOS, and in actual use, a corresponding switch type may be selected according to needs, which is not described herein.
As shown in fig. 1, the error amplifier 12 receives the feedback voltage VFB and a reference voltage VBG output by the feedback unit 11, amplifies a difference between the feedback voltage VFB and the reference voltage VBG, and outputs the amplified difference to the control terminal of the power switch M1.
Specifically, as an example, the non-inverting input terminal of the error amplifier 12 is connected to the feedback voltage VFB, and the inverting input terminal is connected to the reference voltage VBG; in practical use, the correspondence between the polarity of the input terminal of the error amplifier 12 and the input signal may be set according to actual needs, so as to ensure that the feedback voltage VFB is negative feedback.
Specifically, in the present embodiment, the reference voltage VBG is a voltage generated by a Band Gap reference circuit (Band Gap) inside the chip. As an example, the reference voltage VBG is 1.2V; the value of the reference voltage VBG can be set as desired in practical use.
As shown in fig. 1, one end of the feedback unit 11 is connected to the second end of the power switch M1, and the other end is grounded; the feedback unit 11 feeds back the voltage sample at the second end of the power switch M1 to the error amplifier 12 when the ldo linear regulator 1 is operating, and reduces the charge loss on the first capacitor C1 when the ldo linear regulator 1 stops operating.
Specifically, in this embodiment, the feedback unit 11 includes a first resistor R1, a second resistor R2, a third resistor R3, and a first switch SW1, wherein the first resistor R1, the second resistor R2, and the third resistor R3 are sequentially connected in series to the second end of the power switch M1, the first switch SW1 is connected in parallel to two ends of the third resistor R3, and the first switch SW1 receives a control signal CTL 0; the feedback voltage VFB is output between the first resistor R1 and the second resistor R2. As an example, the second resistor R2 is an adjustable resistor, and different values of the power supply voltage can be obtained by adjusting the resistance of the second resistor R2, so as to meet different power supply voltage requirements, and expand the application range of the low dropout regulator 1. As an example, the first switch SW1 is implemented by using an NMOS, and in actual use, a corresponding switch type may be selected according to needs, which is not described herein.
Specifically, when the low dropout linear regulator 1 stops operating, the charge in the first capacitor C1 is discharged to the ground through the feedback unit 11; the third resistor R3 is used to be connected in series with the first resistor R1 and the second resistor R2 when the low dropout regulator 1 stops working, so as to increase the resistance of the leakage path where the feedback unit 11 is located, and further reduce the leakage current. The higher the resistance of the third resistor R3 is, the lower the bleed current is, and therefore, the larger the resistance of the third resistor R3 is, the better theoretically is. In this embodiment, the resistance of the third resistor R3 is greater than the sum of the resistances of the first resistor R1 and the second resistor R2; as an example, in order to greatly reduce power consumption, the third resistor R3 has a resistance value greater than 10 megaohms (ohm); as another example, the third resistor R3 may be set to have a resistance value of 2 megohms to 10 megohms (inclusive) for the purpose of cost and power consumption reduction.
It should be noted that the third resistor R3 does not need to be matched with the first resistor R1 and the second resistor R2, and the process types of the resistors do not need to be consistent, so that the third resistor R3 with a resistance value of tens of mega ohms or even larger can be realized at a low area cost. In practical use, the resistance of the third resistor R3 can be set as required, so as to reduce the leakage current and meet the requirements of power consumption and time duration, which is not limited in this embodiment.
Specifically, as another implementation manner of the present invention, the feedback unit 11 further includes a third capacitor C3, and the third capacitor C3 is connected in parallel to two ends of the first resistor R1. The third capacitor C3, the first resistor R1 and the second resistor R2 form a zero pole, which can achieve the function of a stable circuit.
As shown in fig. 2, the operation principle of the low dropout regulator 1 of the present embodiment is as follows:
11) turning on the first switch SW1 and starting the low dropout regulator 1, the first capacitor C1 is charged to a preset voltage and stabilized at the preset voltage.
Specifically, in the present embodiment, the first switch SW1 is first turned on based on the control signal CTL0, so that the third resistor R3 is short-circuited; the second switch SW2 is turned off based on an enable signal EN _ LDO (high level), so that the low dropout linear regulator 1 starts to start operating. As shown in fig. 2, the low dropout regulator 1 charges the first capacitor C1 (from 0V to a predetermined voltage at the first start-up; from the voltage remaining on the first capacitor C1 to a predetermined voltage at the intermediate start-up) and stabilizes at the predetermined voltage. The voltage VLDO on the first capacitor C1 is determined by the first resistor R1, the second resistor R2 and the reference voltage VBG, and a predetermined voltage satisfies the relationship: VLDO ═ VBG (R1+ R2)/R2, where VBG is the value of the reference voltage, R1 is the resistance value of the first resistor, and R2 is the resistance value of the second resistor.
It should be noted that, in this embodiment, step 11) corresponds to a first start, and at this time, the first capacitor C1 is charged from 0V to a preset voltage; in practical applications, step 11) may also correspond to an intermediate starting process, where the first capacitor C1 is charged from the voltage retained at C1 to a preset voltage; the present embodiment is not limited thereto.
12) When the power supply is over, the low dropout linear regulator 1 stops working, the first switch SW1 is opened, and the first capacitor C1 discharges to the ground through the feedback unit 11.
Specifically, after the power supply is completed, the enable signal EN _ LDO jumps to a low level, the second switch SW2 is turned on, so that the gate of the power switch M1 is at a high level, and the low dropout linear regulator 1 stops working; the first switch SW1 is turned off based on a control signal CTL0, so that the third resistor R3 is switched into a path of the first resistor R1 and the second resistor R2. The charge on the first capacitor C1 is discharged to ground through the first resistor R1, the second resistor R2 and the third resistor R3; due to the addition of the third resistor R3, the resistance of the bleeding path where the feedback unit 11 is located is increased, so as to reduce the bleeding current, where the bleeding current is only VLDO/(R1+ R2+ R3) at maximum, where R3 is the resistance of the third resistor; when the third resistor R3 is much larger (at least one order of magnitude larger) than the sum of the resistances of the first resistor R1 and the second resistor R2, the leakage current can be made small, so that the voltage of the first capacitor C1 is slowly reduced in proportion to the magnitude of the leakage current, as shown in fig. 2, thereby completing a power supply process.
13) Turning on the first switch SW1 and starting the low dropout regulator 1, charging the first capacitor C1, and complementing the charge discharged from the first capacitor C1 through the feedback unit 11, so that the voltage across the first capacitor C1 is stabilized at the preset voltage.
Specifically, when the next power supply is performed, the operation method is the same as that in step 11), since part of the charge on the first capacitor C1 is lost, the voltage VLDO on the first capacitor C1 is lower than the preset voltage, and the low dropout linear regulator 1 needs to recharge the first capacitor C1 to the preset voltage to compensate for the charge drained by the first capacitor C1 through the feedback unit 11. Because the leakage current is small, when the low dropout linear regulator 1 restarts, a large amount of charge is still stored in the first capacitor C1, and therefore, the extra charge amount that the power supply voltage VDD supplements to the first capacitor C1 through the power switch tube M1 is small, which can effectively reduce the power consumption and time consumption of the low dropout linear regulator 1 during starting.
It should be noted that, if the next start is needed, step 12) and step 13) may be continuously and repeatedly executed to reduce power consumption and time duration of each start, which is not described herein again. If the next starting is not needed, the operation can be directly ended, and the power is cut off (VDD is low level); the specific operation is set by actual requirements, and is not limited to the embodiment.
It should be noted that, as an example, after the first switch SW1 is turned on, the low dropout regulator 1 starts to operate after a preset time, so as to ensure the stability of the circuit operation.
As shown in fig. 2, VLDO is the voltage on the first capacitor C1, and I _ Power is the Power consumption curve of this embodiment; Δ V is a voltage variation of the first capacitor C1, I _ MAX1a is a transient power consumption at the first start, I _ MAX2a is a transient power consumption at the second or later start, and I _ STA1a is an intrinsic power consumption when the ldo is not connected to a load for operation. As can be seen, I _ MAX2a is significantly smaller than I _ MAX1a, which can effectively reduce power consumption during startup, and the startup duration is also greatly shortened.
Example two
As shown in fig. 3, the present embodiment provides a low dropout regulator 1, which is different from the first embodiment in that in the present embodiment, the feedback unit 11 includes a first resistor R1, a second resistor R2, a second capacitor C2 and a first switch SW 1.
Specifically, the first resistor R1, the second resistor R2 and the second capacitor C2 are sequentially connected in series to a second end of the power switch M1, the first switch SW1 is connected in parallel to two ends of the second capacitor C2, and the first switch SW1 receives a control signal CTL 0; the feedback voltage VFB is output between the first resistor R1 and the second resistor R2.
Specifically, the upper plate of the second capacitor C2 is connected to the second resistor R2, and the lower plate is grounded. When the LDO1 stops working, the first capacitor C1 and the second capacitor C2 are charge-shared; the charges discharged by the first capacitor C1 are stored in the second capacitor C2, that is, Q is VLDO1 × C1 ═ VLDO2 ═ C1+ C2, VLDO2 ═ VLDO1 × C1/(C1+ C2), where Q is the total charge amount, VLDO1 is the output voltage value when the low dropout linear regulator 1 is operating normally, C1 is the capacitance value of the first capacitor, VLDO2 is the output voltage value after the low dropout linear regulator 1 stops operating, and C2 is the capacitance value of the second capacitor; therefore, the smaller the capacity of the second capacitor is, the less the charge discharged by the first capacitor C1 is, the VLDO2 is approximately close to the VLDO1, and the next time the low dropout linear regulator 1 starts to operate, the first capacitor C1 is hardly required to be supplemented with additional charge, so that the power consumption and the time length during starting are saved. Therefore, theoretically, the smaller the capacitance of the second capacitor, the better, in this embodiment, the capacitance of the second capacitor C2 is such that the voltage variation on the first capacitor C1 is smaller than the set value when the low dropout linear regulator 1 stops operating (i.e. the voltage on the first capacitor C1 is considered to be stable within the set value range). The second capacitor C2 is small, and occupies a small area.
It should be noted that the capacity of the second capacitor C2 may be set as needed, and the requirements of storing the electric charge released by the first capacitor and meeting the power consumption and time duration overhead requirements may be met, which is not limited to the embodiment.
The connection relationship and the operation principle of other devices are the same as those in the first embodiment, and are not described in detail here.
As shown in fig. 4, the operation principle of the low dropout regulator 1 of the present embodiment is as follows:
21) the first switch SW1 is turned on and the low dropout regulator 1 is turned on, so that the first capacitor C1 is charged to a preset voltage and stabilized at the preset voltage.
Specifically, the first switch SW1 is turned on based on the control signal CTL0, so that the second capacitor C2 is short-circuited. The detailed operation and principles are similar to those of the embodiments and are not repeated herein.
22) When the power supply is over, the low dropout regulator 1 stops working, the first switch SW1 is turned off, and the first capacitor C1 discharges to the feedback unit 11 and is stored in the second capacitor C2 of the feedback unit 11.
Specifically, after the power supply is completed, the enable signal EN _ LDO jumps to a low level, and the low dropout linear regulator 1 stops working; the first switch SW1 is turned off based on a control signal CTL0, so that the second capacitor C2 is connected to a path of the first resistor R1 and the second resistor R2. The charge on the first capacitor C1 is stored into the second capacitor C2 through the first resistor R1 and the second resistor R2, and no bleeding path exists. When the capacity of the second capacitor C2 is small, the voltage on the first capacitor C1 is substantially constant (the variation range is smaller than the set value), as shown in fig. 4, thereby completing a power supply process.
23) Turning on the first switch SW1, the second capacitor SW2 drains the stored charge to the first capacitor C1; and starting the low dropout regulator 1 to stabilize the voltage on the first capacitor C1 at the preset voltage.
Specifically, the first switch SW1 is turned on first, and the low dropout linear regulator 1 is enabled, and a short delay Td (preset time) exists between the control signal CTL0 and the enable signal; when the first switch SW1 is turned on, the charges stored in the second capacitor C2 are firstly discharged to the first capacitor C1, after the Td delay, the charges in the first capacitor C1 are not discharged through the first resistor R1 and the second resistor R2, the low dropout linear regulator 1 is enabled to start operating, and then the current of the branch where the first resistor R1, the second resistor R2, and the first switch SW1 are located is provided by the power supply voltage VDD through the power switch tube M1, so that the voltage across the first capacitor C1 does not change abruptly. If the second capacitor C2 does not exist, after the first switch SW1 is turned on, the charges on the first capacitor C1 are discharged immediately through the branch where the first resistor R1, the second resistor R2 and the first switch SW1 are located, the voltage on the first capacitor C1 changes suddenly, the low dropout linear regulator 1 is enabled to be turned on after Td delay, and the power supply voltage VDD supplies charges to the first capacitor C1 through the power switch tube M1.
As shown in fig. 4, I _ Power is a Power consumption curve of the present embodiment, and I _ STA1b is an intrinsic Power consumption of the ldo linear regulator when the ldo linear regulator is not connected to a load to operate. It can be seen that the power consumption of the present embodiment is almost 0, and there is no problem of the startup duration.
EXAMPLE III
As shown in fig. 5, the present embodiment provides a low power consumption power supply circuit, including:
n gating switches (S1, S2 … Sn), a logic control module 2, and the low dropout regulator 1 according to the first embodiment or the second embodiment, wherein n is a natural number greater than or equal to 1.
As shown in fig. 5, the logic control module 2 is configured to generate an enable signal EN _ LDO, a control signal CTL0, and n strobe signals; the enable signal EN _ LDO is used for enabling the low dropout linear regulator 1 to operate, the control signal CTL0 is used for controlling the operating state of the first switch SW1, and the gating signal is used for gating the power supply path of the corresponding power utilization circuit.
Specifically, the internal structure of the logic control module 2 is not limited, and the n gating switch sets and the low dropout linear regulator 1 can be controlled, which is not described herein.
As shown in fig. 5, the input end of each gating switch is connected to the output end of the low dropout regulator 1, and each gating switch receives a corresponding gating signal.
Specifically, the number of the gate switches may be set as needed.
It should be noted that, as an example, the low power consumption power supply circuit may be disposed in a chip, and PADs of the chip at least include PAD0 connected to the first capacitor C1 and PADs PAD1 to PAD0 connected to output terminals of the gate switches.
Example four
As shown in fig. 6, the present embodiment provides an electronic apparatus, including:
a first capacitor C1, m power utilization circuits and a low-power-consumption power supply circuit of the third embodiment, wherein m is a natural number larger than or equal to 1.
As shown in fig. 6, an upper plate of the first capacitor C1 is connected to an output terminal of the low dropout linear regulator 1 in the low power consumption power supply circuit, and a lower plate is grounded.
Specifically, in the present embodiment, the capacity of the first capacitor C1 is 1uF, and the capacity of the first capacitor can be set according to actual needs, which is not limited to the present embodiment.
As shown in fig. 6, each of the power consuming circuits is connected to the output terminal of the corresponding gate switch, and obtains a power supply based on the corresponding gate signal.
Specifically, as an example, each gating switch is connected to one electric circuit, in practical use, the number of the electric circuits corresponding to each gating switch may be set according to needs, and the electric circuits include, but are not limited to, a sensor (e.g., a pressure sensor) or any electric circuit powered by a low dropout linear regulator, and is not limited to this embodiment. For other working principles, see above, they are not repeated herein.
To sum up, the utility model provides a low dropout linear regulator, low-power consumption supply circuit and electronic equipment, include: the power switch tube, the feedback unit and the error amplifier; the first end of the power switch tube is connected with a power supply voltage, and the second end of the power switch tube is grounded through the feedback unit; the power switching tube and the connection node of the feedback unit output a power supply; the error amplifier receives the feedback voltage output by the feedback unit and a reference voltage, amplifies the difference between the feedback voltage and the reference voltage and outputs the amplified difference to the control end of the power switch tube; the feedback unit samples and feeds back the voltage of the second end of the power switch tube to the error amplifier when the low dropout regulator works, and the charge loss on the first capacitor is reduced when the low dropout regulator stops working. The utility model discloses a low dropout regulator, low-power consumption supply circuit and electronic equipment supply for external electric capacity through the discharge current that reduces the external electric capacity of LDO or keep the back with the electric charge that the external electric capacity of LDO was released, consumption when greatly reduced LDO starts with long time spending, improve the stability of LDO. Therefore, the utility model effectively overcomes various defects in the prior art and has high industrial utilization value.
The above embodiments are merely illustrative of the principles and effects of the present invention, and are not to be construed as limiting the invention. Modifications and variations can be made to the above-described embodiments by those skilled in the art without departing from the spirit and scope of the present invention. Accordingly, it is intended that all equivalent modifications or changes which may be made by those skilled in the art without departing from the spirit and technical spirit of the present invention shall be covered by the claims of the present invention.
Claims (12)
1. The utility model provides a low dropout regulator, output first electric capacity of connecting in parallel which characterized in that, low dropout regulator includes at least:
the power switch tube, the feedback unit and the error amplifier; the first end of the power switch tube is connected with a power supply voltage, and the second end of the power switch tube is grounded through the feedback unit; a power supply is output from a connection node of the power switch tube and the feedback unit; the error amplifier receives the feedback voltage output by the feedback unit and a reference voltage, amplifies the difference between the feedback voltage and the reference voltage and outputs the amplified difference to the control end of the power switch tube;
the feedback unit samples and feeds back the voltage of the second end of the power switch tube to the error amplifier when the low dropout regulator works, and the charge loss on the first capacitor is reduced when the low dropout regulator stops working.
2. The low dropout linear regulator of claim 1, wherein: the feedback unit comprises a first resistor, a second resistor, a third resistor and a first switch, wherein the first resistor, the second resistor and the third resistor are sequentially connected in series with a second end of the power switch tube, and the first switch is connected in parallel with two ends of the third resistor; the first switch receives a control signal; the feedback voltage is output between the first resistor and the second resistor.
3. The low dropout regulator according to claim 2, wherein: the resistance value of the third resistor is larger than the sum of the resistance values of the first resistor and the second resistor.
4. The low dropout linear regulator of claim 3, wherein: the resistance value of the third resistor is larger than 10 mega ohms.
5. The low dropout regulator of claim 3, wherein: the resistance value of the third resistor is set to be 2 megohm-10 megohm.
6. The low dropout linear regulator of claim 1, wherein: the feedback unit comprises a first resistor, a second capacitor and a first switch, wherein the first resistor, the second resistor and the second capacitor are sequentially connected in series with a second end of the power switch tube, and the first switch is connected in parallel with two ends of the second capacitor; the first switch receives a control signal; the feedback voltage is output between the first resistor and the second resistor.
7. The low dropout linear regulator according to any one of claims 2 to 6, wherein: the second resistor is an adjustable resistor.
8. The low dropout regulator according to any one of claims 2 to 6, wherein: the feedback unit further comprises a third capacitor, and the third capacitor is connected in parallel to two ends of the first resistor.
9. The low dropout regulator according to any one of claims 1 to 6, wherein: the low dropout regulator further comprises a second switch, one end of the second switch is connected with the power voltage, the other end of the second switch is connected with the control end of the power switch tube, and the second switch receives an enabling signal.
10. A low power supply circuit, characterized in that the low power supply circuit comprises at least:
n gating switches, a logic control module and the low dropout linear regulator according to any one of claims 1 to 9;
the logic control module is used for generating an enabling signal, a control signal and n gating signals; the enabling signal is used for starting the low dropout linear regulator to work, the control signal is used for controlling the working state of the first switch, and the gating signal is used for gating a power supply path of a corresponding power utilization circuit;
the input end of each gating switch is connected with the output end of the low dropout linear regulator, and each gating switch receives a corresponding gating signal;
wherein n is a natural number of 1 or more.
11. An electronic device, characterized in that the electronic device comprises at least:
a first capacitor, m power consuming circuits and a low power consumption power supply circuit as claimed in claim 10;
the upper polar plate of the first capacitor is connected with the output end of the low-voltage-difference linear voltage stabilizer in the low-power-consumption power supply circuit, and the lower polar plate is grounded;
each circuit is respectively connected with the output end of the corresponding gating switch, and acquires a power supply based on the corresponding gating signal;
wherein m is a natural number of 1 or more.
12. The electronic device of claim 11, wherein: the power utilization circuit is a pressure sensor.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202123440869.2U CN217238691U (en) | 2021-12-31 | 2021-12-31 | Low dropout regulator, low power consumption power supply circuit and electronic equipment |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202123440869.2U CN217238691U (en) | 2021-12-31 | 2021-12-31 | Low dropout regulator, low power consumption power supply circuit and electronic equipment |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN217238691U true CN217238691U (en) | 2022-08-19 |
Family
ID=82828385
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202123440869.2U Active CN217238691U (en) | 2021-12-31 | 2021-12-31 | Low dropout regulator, low power consumption power supply circuit and electronic equipment |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN217238691U (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116436132A (en) * | 2023-06-13 | 2023-07-14 | 中科海高(成都)电子技术有限公司 | Charging circuit and charging method |
| CN116540817A (en) * | 2023-05-24 | 2023-08-04 | 深圳飞渡微电子有限公司 | Self-powered charge pump type high-power supply rejection ratio LDO circuit and control method thereof |
-
2021
- 2021-12-31 CN CN202123440869.2U patent/CN217238691U/en active Active
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116540817A (en) * | 2023-05-24 | 2023-08-04 | 深圳飞渡微电子有限公司 | Self-powered charge pump type high-power supply rejection ratio LDO circuit and control method thereof |
| CN116436132A (en) * | 2023-06-13 | 2023-07-14 | 中科海高(成都)电子技术有限公司 | Charging circuit and charging method |
| CN116436132B (en) * | 2023-06-13 | 2023-09-19 | 中科海高(成都)电子技术有限公司 | Charging circuit and charging method |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN217238691U (en) | Low dropout regulator, low power consumption power supply circuit and electronic equipment | |
| CN113110694B (en) | Low dropout regulator circuit with current surge suppression | |
| US6414537B1 (en) | Voltage reference circuit with fast disable | |
| CN109861329B (en) | Linear charging system, constant-current constant-voltage control circuit and voltage following control method thereof | |
| US20150042296A1 (en) | Voltage regulator soft start | |
| CN103677047B (en) | LDO fast start circuit | |
| JP2001117650A (en) | Fixed voltage power source | |
| CN101051233A (en) | Voltage regulating circuit and voltage regulating method for preventing input voltage sudden fall | |
| CN108241396A (en) | A kind of low pressure difference linear voltage regulator for improving transient response speed | |
| CN111625043B (en) | Adjustable ultra-low power consumption full CMOS reference voltage current generation circuit | |
| US11300985B2 (en) | Voltage regulator | |
| CN117155123B (en) | Transient jump overshoot suppression circuit suitable for LDO and control method thereof | |
| CN115777089A (en) | Low dropout voltage regulator for low voltage applications | |
| US6525517B1 (en) | Power supply circuit with a soft starting circuit | |
| US11709515B1 (en) | Voltage regulator with n-type power switch | |
| KR20060125565A (en) | Constant voltage power supply circuit and method of controlling the same | |
| CN110703842B (en) | High-speed electrification overshoot-prevention circuit for band-gap reference voltage | |
| CN110673680B (en) | Linear voltage stabilizer circuit | |
| CN117270616A (en) | Band gap module and linear voltage stabilizer | |
| CN108319317B (en) | Comparison device and linear voltage stabilizing device comprising same | |
| US8582267B2 (en) | System and method to limit in-rush current | |
| CN109582073B (en) | Half-period capacitance ratio programmable band-gap reference circuit | |
| CN114326890A (en) | Voltage regulating circuit | |
| CN108459644A (en) | Low voltage difference stable-pressure device and its operating method | |
| CN208459893U (en) | A kind of reference circuit applied in Internet of Things |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant |