阅读说明：本技术 升压产生电路以及相关电路、芯片以及穿戴设备 (Boost generation circuit and related circuit, chip and wearing equipment ) 是由 王文祺 于 2019-10-08 设计创作，主要内容包括：本申请公开了一种升压产生电路(10)以及相关电路、芯片以及穿戴设备。所述升压产生电路,具有输出端(OUT),所述输出端提供输出电压(V<Sub>OUT</Sub>)及负载电流(I<Sub>LOAD</Sub>)。所述升压产生电路包括：第一电荷泵(100),提供第一偏置电流(IB1)；第二电荷泵(102),提供所述负载电流；输出电压锁定电路(110),从所述第一电荷泵抽取所述第一偏置电流至所述输出端,其中所述输出电压锁定电路藉由锁定所述第一偏置电流来锁定所述第一电荷泵的第一电荷泵电压(V<Sub>PUMP1</Sub>),并进一步基于被锁定的所述第一电荷泵电压来锁定所述输出电压；以及负载电流产生电路(120),基于所述第二电荷泵的第二电荷泵电压(V<Sub>PUMP2</Sub>)从所述第二电荷泵抽取所述负载电流至所述输出端。(The application discloses boost generation circuit (10) and relevant circuit, chip and wearing equipment. The boost generation circuit has an output terminal (OUT) providing an output voltage (V) OUT ) And load current (I) LOAD ). The boost generation circuit includes: a first charge pump (100) providing a first bias current (IB 1); a second charge pump (102) providing the load current; an output voltage locking circuit (110) that latches a first charge pump voltage (Vpump) of the first charge pump by latching the first bias current to the output terminal PUMP1 ) And further locking the output voltage based on the first charge pump voltage being locked; and a load current generating circuit (120) based on a second charge pump voltage (V) of the second charge pump PUMP2 ) Drawing the load current from the second charge pump to the output.)

1. A boost generation circuit having an output for providing an output voltage and a load current to a high voltage circuit external to the boost generation circuit, the boost generation circuit comprising:

a first charge pump for providing a first bias current;

a second charge pump to provide the load current;

an output voltage locking circuit coupled between the first charge pump and the output terminal of the boost generation circuit for pumping the first bias current from the first charge pump to the output terminal of the boost generation circuit, wherein the output voltage locking circuit locks a first charge pump voltage of the first charge pump by locking the first bias current and further locks the output voltage of the output terminal of the boost generation circuit based on the locked first charge pump voltage; and

a load current generating circuit coupled between the second charge pump and the output of the boost generating circuit for drawing the load current from the second charge pump to the output of the boost generating circuit based on a second charge pump voltage of the second charge pump.

2. The boost generation circuit of claim 1, wherein the output voltage locking circuit comprises:

a first current source is coupled to the first charge pump for drawing the first bias current of a fixed magnitude from the first charge pump.

3. The boost generation circuit of claim 2, wherein the output voltage locking circuit further comprises:

an input stage transistor coupled to the first current source, wherein a gate-source voltage of the input stage transistor is locked based on the first bias current of a fixed magnitude.

4. The boost generation circuit of claim 3, wherein the input stage transistor is coupled in series between the first current source and the output of the boost generation circuit, and a gate of the input stage transistor is coupled to the first charge pump.

5. The boost generation circuit of claim 4, wherein the output voltage of the output of the boost generation circuit is a voltage difference between the first charge pump voltage and the gate-source voltage of the input stage transistor.

6. The boost generation circuit of claim 1, wherein the load current generation circuit comprises:

and the output stage transistor is connected between the second charge pump and the output end of the boosting generation circuit in series.

7. The boost generation circuit of claim 6, wherein a gate voltage of the output stage transistor is locked based at least on the first bias current.

8. The boost generation circuit of claim 1, wherein the boost generation circuit further comprises:

the control circuit is coupled between the output voltage locking circuit and the load current generating circuit and used for controlling the load current generating circuit based on the output voltage so as to adjust the magnitude of the load current.

9. The boost generation circuit of claim 8, wherein the control circuit further comprises:

a second current source to draw a second bias current of a fixed magnitude from the first charge pump.

10. The boost generation circuit of claim 9, wherein the control circuit comprises:

a control transistor, wherein a gate-source voltage of the control transistor is locked based on the second bias current of a fixed magnitude.

11. The boost generation circuit of claim 10, wherein a gate of the control transistor is coupled to the output voltage locking circuit, and the control transistor is connected in series between the first charge pump and the load current generation circuit.

12. The boost generation circuit of claim 1, further comprising:

and the low-pass filter is coupled between the first charge pump and the output voltage locking circuit and is used for filtering the first charge pump voltage.

13. The boost generation circuit of claim 1, wherein the first bias current is less than the load current.

14. A circuit, characterized in that the circuit comprises:

the boost generation circuit of any one of claims 1-13; and

the high-voltage circuit.

15. The circuit of claim 14, wherein the high voltage circuit comprises a rail-to-rail input amplifier.

16. A chip, wherein the chip comprises:

a circuit as claimed in any one of claims 14 to 15.

17. A wearable device, characterized in that the wearable device comprises:

the chip of claim 16.

Technical Field

The present application relates to a power supply technology, and in particular, to a boost generation circuit, a related circuit, a chip, and a wearable device.

Background

With the development and progress of science and technology, mobile electronic devices such as mobile phones, digital cameras, tablet computers, notebook computers and the like have become indispensable tools in people's lives. These electronic devices are usually supplied with a supply voltage by a battery of the electronic device or an external power source of the electronic device. In some applications, the internal circuitry of the electronic device requires an operating voltage higher than the supply voltage. Therefore, the supply voltage needs to be boosted by a boosting circuit. The characteristics of the voltage output by the conventional boost circuit are not good, thereby affecting the performance of the internal circuit. In order to make the internal circuit perform its intended function, it is an important task to improve the characteristics of the voltage output from the boost circuit.

Disclosure of Invention

An objective of the present application is to disclose a power supply technology, and in particular, to a boost generation circuit, a related circuit, a chip and a wearable device, so as to solve the above problems.

An embodiment of the present application discloses a boost generation circuit. The boost generation circuit is provided with an output end which is used for providing output voltage and load current to a high-voltage circuit outside the boost generation circuit. The boost generation circuit includes: a first charge pump for providing a first bias current; a second charge pump to provide the load current; an output voltage locking circuit coupled between the first charge pump and the output terminal of the boost generation circuit for pumping the first bias current from the first charge pump to the output terminal of the boost generation circuit, wherein the output voltage locking circuit locks a first charge pump voltage of the first charge pump by locking the first bias current and further locks the output voltage of the output terminal of the boost generation circuit based on the locked first charge pump voltage; and a load current generating circuit coupled between the second charge pump and the output of the boost generating circuit for drawing the load current from the second charge pump to the output of the boost generating circuit based on a second charge pump voltage of the second charge pump.

An embodiment of the present application discloses a circuit. The circuit comprises: the aforementioned boost generation circuit; and the high voltage circuit.

An embodiment of the present application discloses a chip. The chip includes: the foregoing circuit.

An embodiment of the application discloses a wearable device. The wearing apparatus includes: the chip described above.

The boost generation circuit disclosed by the application comprises two charge pumps, a first charge pump and a second charge pump. The two charge pumps are respectively responsible for the output voltage and the load current. In short, the output voltage and the load current are not provided by the same charge pump, so the output voltage is not interfered by the load current, and the characteristics of the output voltage are better.

Drawings

Fig. 1 is a circuit diagram of a first embodiment of a boost generation circuit of the present application.

Fig. 2 is a circuit diagram of an embodiment of a charge pump of the present application.

Fig. 3 is a circuit diagram of a second embodiment of the boost generation circuit of the present application.

Fig. 4 is a circuit diagram of a third embodiment of the boost generation circuit of the present application.

Fig. 5 is a waveform diagram of the related voltages of the boost generation circuit of fig. 4.

Fig. 6 is a schematic diagram of an embodiment of a wearable device to which a chip including the boost generation circuit of the present application is applied.

Detailed Description

The following disclosure provides various embodiments or illustrations that can be used to implement various features of the disclosure. The embodiments of components and arrangements described below serve to simplify the present disclosure. It is to be understood that such descriptions are merely illustrative and are not intended to limit the present disclosure. For example, in the description that follows, forming a first feature on or over a second feature may include certain embodiments in which the first and second features are in direct contact with each other; and may also include embodiments in which additional elements are formed between the first and second features described above, such that the first and second features may not be in direct contact. In addition, the present disclosure may repeat reference numerals and/or characters in the various embodiments. This repetition is for the purpose of simplicity and clarity and does not in itself dictate a relationship between the various embodiments and/or configurations discussed.

Moreover, spatially relative terms, such as "under," "below," "over," "above," and the like, may be used herein to facilitate describing a relationship between one element or feature relative to another element or feature as illustrated in the figures. These spatially relative terms are intended to encompass a variety of different orientations of the device in use or operation in addition to the orientation depicted in the figures. The device may be otherwise oriented (e.g., rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

Although numerical ranges and parameters setting forth the broad scope of the application are approximations, the numerical values set forth in the specific examples are reported as precisely as possible. Any numerical value, however, inherently contains certain standard deviations found in their respective testing measurements. As used herein, "the same" generally means that the actual value is within plus or minus 10%, 5%, 1%, or 0.5% of a particular value or range. Alternatively, the term "the same" means that the actual value falls within the acceptable standard error of the mean, subject to consideration by those of ordinary skill in the art to which this application pertains. It is understood that all ranges, amounts, values and percentages used herein (e.g., to describe amounts of materials, length of time, temperature, operating conditions, quantitative ratios, and the like) are "the same" unless otherwise specifically indicated or indicated. Accordingly, unless indicated to the contrary, the numerical parameters set forth in the specification and attached claims are approximations that may vary depending upon the desired properties sought to be obtained. At the very least, these numerical parameters are to be understood as meaning the number of significant digits recited and the number resulting from applying ordinary carry notation. Herein, numerical ranges are expressed from one end to the other or between the two ends; unless otherwise indicated, all numerical ranges set forth herein are inclusive of the endpoints.

The magnitude of the output voltage of the charge pump and the magnitude of the ripple voltage of the output voltage are both influenced by the magnitude of the output current (i.e., the load current) of the charge pump. Generally, the load current causes the output voltage of the charge pump to become small and the ripple voltage of the output voltage to become large, especially when the load current is larger, the smaller the output voltage of the charge pump and the larger the ripple voltage of the output voltage. The boost generation circuit disclosed in the present application includes two charge pumps, which are respectively responsible for outputting voltage and load current. That is, the output voltage and the load current are not provided by the same charge pump, so the magnitude of the output voltage and the magnitude of the ripple voltage of the output voltage are not affected by the magnitude of the load current, and the details thereof are described below.

Fig. 1 is a circuit diagram of a first embodiment of a boost voltage generation circuit 10 according to the present application. Referring to fig. 1, the boost generation circuit 10 has an output terminal OUT. The output terminal OUT is used for providing an output voltage V_OUTAnd a load current I_LOADTo the high voltage circuit 20 outside the boost generation circuit 10. Output voltage V_OUTAs a supply voltage for the high voltage circuit 20. In some embodiments, the high voltage circuit 20 requires a voltage higher than the power supply voltage of the circuitry as its supply voltage. That is, the high-voltage circuit is a circuit that needs the voltage output by the boost generation circuit provided by the present application to supply power. For example, the high voltage circuit 20 includes a rail-to-rail input amplifier. In this embodiment, the differential pair transistors of the rail-to-rail input amplifier receive the output voltage V_OUTAs the supply voltage of the differential pair transistor, the boost generation circuit 10 of the present application can enhance the performance of the rail-to-rail input amplifier because the rail-to-rail input amplifier particularly requires stable voltage and current, but the high voltage circuit 20 is not limited thereto. The boost generation circuit 10 includes a first charge pump 100, a second charge pump 102, an output voltage locking circuit 110, a load current generation circuit 120, and a control circuit 130.

The first charge pump 100 is coupled to a supply voltage V_DD1And based on the supply voltage V_DD1Providing a first charge pump voltage V_PUMP1. In addition, the first charge pump 100 provides a first bias current IB1 and a second bias current IB 2. In other words, the first charge pump voltage V_PUMP1Is the output voltage of the first charge pump 100, and the sum of the first bias current IB1 and the second bias current IB2 is the output current of the first charge pump 100. In some embodiments, the first bias current IB1 and the second bias current IB2 are each 10 microamperes in magnitude.

The second charge pump 102 is coupled to the supply voltage V_DD2And based on the supply voltage V_DD2Providing a second charge pump voltage V_PUMP2. In addition, the second charge pump 102 provides a load current I_LOAD. In other words, the second charge pump voltage V_PUMP2Is the output voltage of the second charge pump 102, and the load current I_LOADIs the output current of the second charge pump 102. Load current I_LOADIs much larger than the output current of the first charge pump 100, in some embodiments, the load current I_LOADIs 1 ma. In some embodiments, the supply voltage V_DD2Same as the supply voltage V_DD1. In some embodiments, the supply voltage V_DD2May be different from the supply voltage V_DD1。

The output voltage locking circuit 110 is coupled between the first charge pump 100 and the output terminal OUT of the boost generation circuit 10, and is used for pumping the first bias current IB1 with a fixed magnitude from the first charge pump 100 to the output terminal OUT of the boost generation circuit 10 based on the first charge pump voltage V_PUMP1Generating an output voltage V_OUT. On the other hand, the control circuit 130 is coupled to the first charge pump 100 for drawing the second bias current IB2 with a fixed magnitude from the first charge pump 100. Since the voltage locking circuit 110 locks the first bias current IB1 and the control circuit 130 locks the second bias current IB2, the first charge pump voltage V of the first charge pump 100 is obtained_PUMP1Can be locked out by the locked out first bias current IB1 and second bias current IB 2. Further, based on the locked first charge pump voltage V_PUMP1The output voltage V of the output terminal OUT of the boost generation circuit 10_OUTCan also be lockedTo suppress the output voltage V as low as possible_OUTThe ripple voltage of (3). Furthermore, the output voltage locking circuit 110 is based on the output voltage V_OUTGenerating a feedback voltage V_FB. When the output voltage V is_OUTWhen the level of (2) is varied, the feedback voltage V_FBThe level of (c) varies accordingly. In some embodiments, the second bias current IB2 is the same as the first bias current IB 1. In some embodiments, the second bias current IB2 may be different from the first bias current IB 1.

In the present disclosure, since the output current of the first charge pump 100 is the sum of the first bias current IB1 and the second bias current IB2, the load current I flowing into the high voltage circuit 20 is not included_LOAD. Thus, the first charge pump voltage V output by the first charge pump 100_PUMP1Will not be subjected to the load current I flowing into the high-voltage circuit 20_LOADThe interference of (2). The output voltage locking circuit 110 is based on the first charge pump voltage V_PUMP1Generating an output voltage V_OUTAnd thus the output voltage V_OUTWill not be subjected to load current I_LOADThe interference of (2).

In addition, the control circuit 130 is coupled between the output voltage locking circuit 110 and the load current generating circuit 120. Control circuit 130 is based on feedback voltage V_FBGenerating a control voltage V_CTRLTo control the load current generating circuit 120. When the output voltage V is_OUTWhen the level fluctuates due to the influence of the ripple voltage, the first bias current IB1 and the second bias current IB2 have fixed magnitudes, so the feedback voltage V_FBWill follow the output voltage V_OUTVary, thereby making the control voltage V_CTRLIs also varied to reverse the output voltage V_OUTThe ripple voltage of (3).

A load current generating circuit 120 coupled between the second charge pump 102 and the output terminal OUT of the boost generating circuit 10 for generating a second charge pump voltage V based on the second charge pump 102_PUMP2Drawing a load current I from the second charge pump 102_LOADTo the output OUT of the boost generation circuit 10. It should be noted that although the output voltage locking circuit 110 and the load current generating circuit 120 are both coupled to the high voltage circuit 20, the output voltage is not limited to the output voltageThe magnitude of the first bias current IB1 output by the voltage locking circuit 110 has been locked, and the load current I flowing into the high voltage circuit 20_LOADDoes not affect the magnitude of the already locked-in first bias current IB1, that is, the load current I flowing into the high-voltage circuit 20_LOADIt can be regarded as being provided by the load current generating circuit 120, and the output voltage locking circuit 110 does not participate in the load current I_LOADIs provided. Also, although the second charge pump voltage V_PUMP2Will be subjected to a load current I_LOADBut the second charge pump voltage V_PUMP2And an output voltage V_OUTSubstantially independent, output voltage V_OUTHas been locked by the output voltage locking circuit 110.

The load current generating circuit 120 is controlled by the control circuit 130. When the output voltage V is_OUTWhen the level fluctuates due to the influence of the ripple voltage, the control circuit 130 outputs the output voltage V_OUTControl load current generating circuit I_LOADTo adjust the load current I_LOADThe size of (2). For example, when the output voltage V is_OUTWhen the level of (b) falls, the control circuit 130 outputs the voltage V based on the output voltage_OUTControl load current generating circuit I_LOADTo draw more load current I from the second charge pump 102_LOADThereby outputting the voltage V_OUTThe falling level pulls back up.

Embodiments of the output voltage locking circuit 110, the load current generating circuit 120, and the control circuit 130 will be described below. However, the voltage locking circuit 110, the load current generating circuit 120 and the control circuit 130 are not limited to the following embodiments, and any circuit architecture capable of implementing the above functions of the voltage locking circuit 110, the load current generating circuit 120 and the control circuit 130 does not depart from the scope of the present disclosure.

The output voltage locking circuit 110 includes a first current source I1 and an input stage transistor M_IN. The first current source I1 is coupled to the first charge pump 100 for drawing a first bias current IB1 of a fixed magnitude from the first charge pump 100. Input stage transistor M_INConnected in series between the first current source I1 and the output terminal OUT of the boost generation circuit 10, and the input stage transistor M_INIs coupled to the first charge pump 100. Since the first bias current IB1 with a fixed magnitude flows through the input stage transistor M_INInput stage transistor M based on the operating principle of the transistor_INIs locked out based on the fixed magnitude of the first bias current IB 1. Accordingly, when the output voltage V is_OUTWhen the level of (3) is varied, the input stage transistor M_INThe drain voltage (as the feedback voltage V)_FB) The level of (c) varies accordingly. Furthermore, the output voltage V_OUTEquation (1) can be expressed as follows.

V_OUT＝V_G-V_GS(1)

Wherein V_GRepresenting the input stage transistor M_INIs (i.e., the first charge pump voltage V)_PUMP1) And V is_GSRepresenting the input stage transistor M_INThe gate-source voltage of. In short, the output voltage V of the output terminal OUT of the boost generation circuit 10_OUTIs a first charge pump voltage V_PUMP1And an input stage transistor M_INGate-source voltage V of_GSThe voltage difference between them.

The control circuit 130 includes a control transistor M_CTRLAnd a second current source I2. Control transistor M_CTRLIs coupled to the input stage transistor M of the output voltage locking circuit 110_INAnd a control transistor M_CTRLIs connected in series between the first charge pump 100 and the load current generating circuit 120. The second current source I2 receives a supply voltage V_DD3For drawing a second bias current IB2 of a fixed magnitude from the first charge pump 100. Since the second bias current IB2 with fixed magnitude flows in the control transistor M_CTRLControlling the transistor M based on the operating principle of the transistor_CTRLIs locked out based on the fixed magnitude of the second bias current IB 2.

In summary, the input stage transistor M_INGate voltage V of_G(i.e., the first charge pump voltage V_PUMP1) Has been locked by the first current source I1 of the output voltage locking circuit 110 and the second current source I2 of the control circuit 130, and is due to the input stage transistor M_INGate-source voltage V of_GSLocked by the first current source I1 of the output voltage locking circuit 110, the output voltage V is based on the above equation (1)_OUTIs locked to the load current I_LOADIs irrelevant.

The load current generation circuit 120 includes an output stage transistor M_OUTAnd is connected in series between the second charge pump 102 and the output terminal OUT of the boost generation circuit 10. Output stage transistor M_OUTThe load current I drawn from the second charge pump 102_LOADIs determined by the output stage transistor M_OUTThe magnitude of the gate voltage. In this embodiment, when the output stage transistor M_OUTThe larger the gate voltage is, the larger the output stage transistor M_OUTThe larger the gate-source masterwork voltage is, the output stage transistor M_OUTThe more conducting the load current I can be extracted_LOAD。

Output stage transistor M_OUTIs locked based on the first bias current IB1 and the second bias current IB 2. In particular, for example, when the output voltage V is_OUTWhen the level of (C) falls, the input stage transistor M_INThe source voltage of (2) drops. Because the input stage transistor M_INGate-source voltage V of_GSLocked by the first bias current IB1, and the input stage transistor M_INBased on the input stage transistor M_INThe reduced source voltage. Input stage transistor M_INThe drain voltage of the transistor M is controlled_CTRLThe gate voltage of the gate. Because the transistor M is controlled_CTRLIs locked by the second bias current IB2, controls the transistor M_CTRLBased on the drain voltage of the control transistor M_CTRLThe falling gate voltage rises. Control transistor M_CTRLThe drain voltage of the output stage transistor M_OUTThe gate voltage of the gate. Output stage transistor M_OUTBased on the transistor M of the output stage_OUTIs turned on to draw more load current I from the second charge pump 102_LOADOutput voltage V_OUTThe level of (c) rises accordingly.

FIG. 2 is a circuit of an embodiment of the charge pump 30 of the present applicationThe first charge pump 100 and the second charge pump 102 of fig. 1 can be implemented by the charge pump 30. Referring to FIG. 2, the charge pump 30 includes power terminals 32 and 34, an output terminal 36, and a switch SW₀、SW₁、SW₂And SW₃And a capacitor C_FAnd C_H. The power terminal 32 receives a supply voltage V_DDThe power supply terminal 34 receives a reference ground voltage V_SSAnd output terminal 36 outputs charge pump voltage V_PUMP。

When the first charge pump 100 is implemented as the charge pump 30, the power source terminal 32 receives the supply voltage V_DD1The charge pump voltage V output by the output terminal 36_PUMPIs the first charge pump voltage V_PUMP1. When the second charge pump 102 is implemented as the charge pump 30, the power supply terminal 32 receives the supply voltage V_DD2The charge pump voltage V output by the output terminal 36_PUMPIs the second charge pump voltage V_PUMP2。

When operated, switch SW₀And SW₁On, the switch SW₂And SW₃And is not conductive. Capacitor C_FCharging to a supply voltage V_DD. In detail, the capacitor C_FHaving an electrode V_FDAnd V_FU. Electrode V_FDVoltage ratio electrode V_FUIs small and the voltage difference is the supply voltage V_DD. Then, switch SW₀And SW₁Non-conductive, switch SW₂And SW₃And conducting. Electrode V_FDFrom a level of zero to a level of the supply voltage V_DDAccording to this electrode V_FUIs a supply voltage V_DDSupply voltage V pulsed to twice the level_DD. Charge pump voltage V at output 36_PUMPCan be expressed as equation (2):

V_PUMP＝2×V_DD(2)

in the comparative embodiment, the load current and the charge pump voltage V are provided by directly using the charge pump 30_PUMPTo the high voltage circuit coupled to the output terminal 36, problems encountered therewith are described below. Suppose a capacitor C_FAnd C_HThe capacitance values of (a) are equal and are all capacitance values C. At this time, the charge pump voltage V_PUMPExpressed as equation (3):

wherein Fs represents a switch SW₀、SW₁、SW₂And SW₃The switching frequency of (c); and, I_ORepresenting the load current.

By comparing equations (2) and (3), it is clear that there is a load current I_OIn the case of (2), the charge pump voltage V at the output terminal 36_PUMPThan in the absence of load current I_OCharge pump voltage V under circumstances_PUMPIs small.

Furthermore, the charge pump voltage V at the output 36_PUMPThe ripple voltage of (a) may be expressed by equation (4):

wherein V_rippleRepresenting the ripple voltage.

As can be seen from equation (4), when a load current I is present_OWill generate ripple voltage V_ripple. Furthermore, by combining equations (3) and (4), the load current I_OWill influence the charge pump voltage V simultaneously_PUMPAnd ripple voltage V_ripple. When the load current I_OThe larger the charge pump voltage V_PUMPSmaller and smaller ripple voltage V_rippleThe larger it is, the more it represents the charge pump voltage V of the charge pump 30_PUMPThe more severe the distortion. Therefore, the high voltage circuit cannot perform normal performance, even fails. In contrast, in the embodiment of FIG. 1, the first charge pump voltage V_PUMP1Is influenced by the first bias current IB1, but because the first bias current IB1 is much smaller than the load current I_OAnd thus the first charge pump voltage V of fig. 1_PUMP1Does not look like the charge pump voltage V_PUMPThus distorting. To solve this problem, the frequency F can be switched from_SAnd a capacitance value C. When switching the frequency F_SThe higher the charge pump, the more relaxed the charge pump isVoltage V_PUMPDistorted but causes increased switching losses. The larger the capacitance C is, the more the charge pump voltage V can be relaxed_PUMPA distorted condition, but this causes an increase in the layout area of the capacitor.

Referring back to fig. 1, in the embodiment of fig. 1, the charge pump 30 is not directly utilized to provide the load current and the charge pump voltage to the high voltage circuit 20. In the embodiment of fig. 1, the output voltage V is provided by the first charge pump 100 respectively_OUTAnd providing a load current I using the second charge pump 102_LOAD. Thus, the load current I_LOADDoes not affect the output voltage V_OUTAnd the output voltage V_OUTThe magnitude of the ripple voltage of (a). The embodiment of fig. 1 has lower switching losses and smaller layout area given the magnitude of the charge pump voltage and the magnitude of the ripple voltage of the charge pump voltage.

Fig. 3 is a circuit diagram of a second embodiment of the boost generation circuit 40 of the present application. Referring to fig. 3, the boost generation circuit 40 is similar to the boost generation circuit 10 of fig. 1, with the difference that the boost generation circuit 40 further includes a low pass filter 400. The low pass filter 400 is coupled between the first charge pump 100 and the output voltage locking circuit 110 for locking the first charge pump voltage V_PUMP1Filtering to provide a filtered first charge pump voltage V_RTo the output voltage locking circuit 110. The filtered first charge pump voltage V is subject to the low pass filter 400_RWill be less than the first charge pump voltage V_PUMP1Thereby causing the output voltage V of fig. 3_OUTIs less than the output voltage V of fig. 1_OUTThe ripple voltage of (3). The low pass filter 400 includes a resistor 402 and a capacitor 404 connected in series with respect to the first charge pump 100.

Fig. 4 is a circuit diagram of a third embodiment of the boost voltage generation circuit 50 of the present application. Referring to fig. 4, the boost voltage generation circuit 50 is similar to the boost voltage generation circuit 40 of fig. 4, with the difference that the boost voltage generation circuit 50 includes a current source I3, transistors M1, M2, M3, M4, and M5, wherein the first current source I1 includes a transistor M4, and the second current source I2 includes a transistor M5.

Transistors M1 and M2 form a current mirror to provide a bias current I3 in series with transistor M1_BIASThe copying is performed so that the transistor M2 outputs the bias current I_BIAS(i.e., the first bias current IB1 is the bias current I_BIAS). Similarly, transistors M1 and M4 form a current mirror to provide a bias current I to a current source I3 in series with transistor M1_BIASThe copying is performed so that the transistor M4 outputs the bias current I_BIAS. In addition, transistors M3 and M5 form a current mirror to mirror the bias current I output by transistor M2_BIASThe copying is performed so that the transistor M5 outputs the bias current I_BIAS(i.e., the second bias current IB2 is the bias current I_BIAS)。

Fig. 5 is a waveform diagram of the related voltages of the boost generation circuit 50 of fig. 4. Referring to fig. 5, the horizontal axis represents time, and the vertical axis represents voltage. As is clear from FIG. 5, the first charge pump voltage V_PUMP1Greater than the second charge pump voltage V_PUMP2And the first charge pump V_PUMP1Is less than the second charge pump voltage V_PUMP2The ripple voltage of (3).

In addition, after being filtered by the low pass filter 400, the filtered first charge pump voltage V_RIs less than the first charge pump voltage V_PUMP1So that the output voltage V is_OUTIs less than the second charge pump voltage V_PUMP2Wherein the second charge pump voltage V_PUMP2Is the load current I_LOADAnd the result is that.

In some embodiments, a circuit includes the boost generation circuit 10/40/50 and/or the high voltage circuit 20. In some embodiments, a chip including the boost generation circuit 10/40/50 and/or the high voltage circuit 20 may be a semiconductor chip implemented by different processes.

Fig. 6 is a schematic diagram of an embodiment of a wearable device 60 to which the chip 62 including the boost generation circuit 10/40/50 of the present application is applied. Referring to fig. 6, the wearable device 60 includes a chip 62. Wearable device 60 may be, for example, a watch, a necklace, or any other smart wearable device.

The foregoing description has set forth briefly the features of certain embodiments of the present application so that those skilled in the art may more fully appreciate the various aspects of the present disclosure. Those skilled in the art should appreciate that they may readily use the present disclosure as a basis for designing or modifying other processes and structures for carrying out the same purposes and/or achieving the same advantages of the embodiments introduced herein. Those skilled in the art should understand that they can still make various changes, substitutions and alterations herein without departing from the spirit and scope of the present disclosure.