Reference voltage generation circuit, control method, chip and electronic device

Abstract

Embodiments of the present application provide a reference voltage generation circuit, a control method, a chip and an electronic device. The circuit includes a gain adjustment module, a charge storage module and an auxiliary discharge module. The gain adjustment module is configured to amplify a reference voltage based on a gear control signal to output reference voltages of at least two gears in proportion to the reference voltage. The charge storage module is configured to stabilize the reference voltage. The auxiliary discharge module is configured to discharge the charge storage module during switching of the reference voltage from a higher voltage gear to a lower voltage gear, and stop discharging the charge storage module after the reference voltage is switched from the higher voltage gear to the lower voltage gear. In this embodiment, the auxiliary discharge module is used to discharge the charge storage module when the reference voltage is switched from the higher voltage gear to the lower voltage gear, so as to improve the falling speed of the reference voltage and shorten the establishment time of the reference voltage.

Description

Technical Field

[0001] This application relates to the field of circuit technology, specifically to a reference voltage generation circuit, control method, chip, and electronic device. Background Technology

[0002] Reference voltage generation circuits typically receive a reference voltage with poor output drive capability and provide a reference voltage with strong drive capability. They can also be configured with multiple output voltage levels to provide reference voltages for ADCs, DACs, or comparator circuits. However, the settling time for the reference voltage is relatively long when switching from a higher to a lower voltage level.

[0003] invention

[0004] In view of the above problems, embodiments of this application provide a reference voltage generation circuit, control method, chip, and electronic device, which accelerates the rate of decrease of the reference voltage and shortens the establishment time of the reference voltage when the reference voltage switches from a higher voltage level to a lower voltage level.

[0005] In a first aspect, embodiments of this application provide a reference voltage generating circuit, including:

[0006] A gain adjustment module is used to adjust a reference voltage based on a range control signal to output a reference voltage at least two ranges proportional to the reference voltage; the at least two ranges of reference voltage include a first range voltage and a second range voltage.

[0007] An auxiliary discharge module is used to connect to the charge storage module and discharge the charge storage module during the process of switching the reference voltage from the first voltage level to the second voltage level; after the reference voltage switches from the first voltage level to the second voltage level, the discharge of the charge storage module is stopped; wherein, the first voltage level is greater than the second voltage level.

[0008] Secondly, embodiments of this application also provide a control method for a reference voltage generation circuit. The reference voltage generation circuit includes a gain adjustment module, which is used to adjust a reference voltage based on a level control signal to output a reference voltage at least two levels proportional to the reference voltage. The at least two levels of reference voltage include a first level voltage and a second level voltage. The control method includes:

[0009] During the process of switching the reference voltage from the first voltage level to the second voltage level, the charge storage module is discharged; after the reference voltage switches from the first voltage level to the second voltage level, the discharge of the charge storage module stops; wherein, the first voltage level is greater than the second voltage level.

[0010] Thirdly, embodiments of this application also provide a chip including the aforementioned reference voltage generation circuit.

[0011] Fourthly, embodiments of this application also provide an electronic device, including the aforementioned chip or reference voltage generating circuit.

[0012] The reference voltage generation circuit, control method, chip, and electronic device provided in this application embodiment allow the gain adjustment module to adjust the reference voltage based on a level control signal, outputting at least two levels of reference voltage. When the reference voltage switches from a higher voltage level to a lower voltage level, the auxiliary discharge module discharges the charge storage module, increasing the rate of reference voltage decrease and shortening the reference voltage settling time. Furthermore, after the reference voltage switches to a lower voltage level, the discharge to the charge storage module stops; that is, after the reference voltage switches to a lower voltage level, the auxiliary discharge module no longer affects the charge storage module.

[0013] These or other aspects of this application will become more apparent in the following description of the embodiments. Attached Figure Description

[0014] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0015] Figure 1 A schematic diagram of the reference voltage generation circuit provided in an embodiment of this application is shown.

[0016] Figure 2 Another schematic diagram of the reference voltage generation circuit provided in an embodiment of this application is shown.

[0017] Figure 3 This shows another schematic diagram of the reference voltage generation circuit provided in an embodiment of this application.

[0018] Figure 4 This shows another schematic diagram of the reference voltage generation circuit provided in an embodiment of this application.

[0019] Figure 5 A circuit diagram of the reference voltage generation circuit provided in an embodiment of this application is shown.

[0020] Figure 6 A waveform diagram of the reference voltage generation circuit provided in an embodiment of this application is shown.

[0021] Figure 7This shows another schematic diagram of the reference voltage generation circuit provided in an embodiment of this application.

[0022] Figure 8 Another circuit diagram of the reference voltage generation circuit provided in an embodiment of this application is shown. Detailed Implementation

[0023] The embodiments of this application are described in detail below. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application.

[0024] To enable those skilled in the art to better understand the solutions of this application, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0025] In the embodiments of this application, it should be noted that, unless otherwise specified, relational terms such as first and second are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations.

[0026] Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0027] In the description of the embodiments of this application, the words "example" or "for example" are used to indicate exemplification, illustration, or description. Any embodiment or design described as "example" or "for example" in the embodiments of this application is not to be construed as being more preferred or having more advantages than another embodiment or design. The use of the words "example" or "for example" is intended to present relative concepts in a clear manner.

[0028] Furthermore, in the embodiments of this application, "multiple" refers to two or more. Therefore, in the embodiments of this application, "multiple" can also be understood as "at least two". "At least one" can be understood as one or more, such as one, two, or more. For example, including at least one means including one, two, or more, and is not limited to which ones are included. For example, including at least one of A, B, and C, then it could include A, B, C, A and B, A and C, B and C, or A and B and C.

[0029] It should be noted that in the embodiments of this application, "and / or" describes the relationship between associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. In addition, the character " / ", unless otherwise specified, generally indicates that the associated objects before and after it are in an "or" relationship.

[0030] It should be noted that in the embodiments of this application, "connection" can be understood as electrical connection. The connection between two electrical components can be a direct or indirect connection between the two electrical components. For example, the connection between A and B can be a direct connection between A and B, or an indirect connection between A and B through one or more other electrical components.

[0031] In the embodiments of this application, the first terminal / first end of each transistor is one of the source and the drain, and the second terminal / second end of each transistor is the other of the source and the drain. Since the source and drain of a transistor can be structurally symmetrical, they can be structurally indistinguishable. That is, the first terminal / first end and the second terminal / second end of the transistor in the embodiments of this application can be structurally indistinguishable. For example, when the transistor is a P-type transistor, the first terminal / first end is the drain, and the second terminal / second end is the source; for example, when the transistor is an N-type transistor, the first terminal / first end is the drain, and the second terminal / second end is the source.

[0032] In the circuit structure provided by the embodiments of this application, nodes such as the first node and the second node do not represent actual existing components, but rather represent the junction points of related couplings in the circuit diagram. In other words, these nodes are equivalent to the junction points of related couplings in the circuit diagram.

[0033] The following description of the scheme of this application refers to the accompanying drawings. Figure 1The reference voltage generation circuit 100 includes a gain adjustment module 110 and an auxiliary discharge module 120. The gain adjustment module 110 adjusts the reference voltage based on a level control signal to output at least two levels of reference voltage proportional to the reference voltage. The at least two levels of reference voltage include a first level voltage and a second level voltage. The auxiliary discharge module 120 is connected to a charge storage module and discharges the charge storage module during the transition of the reference voltage from the first level voltage to the second level voltage; it stops discharging the charge storage module after the transition. The first level voltage is greater than the second level voltage.

[0034] In this embodiment, the first voltage level is the reference voltage corresponding to the higher voltage level, and the second voltage level is the reference voltage corresponding to the lower voltage level. When switching from a higher voltage level to a lower voltage level, the reference voltage switches from the first voltage level to the second voltage level; conversely, when switching from a lower voltage level to a higher voltage level, the reference voltage switches from the second voltage level to the first voltage level. Adjusting the reference voltage includes amplifying or reducing the reference voltage.

[0035] In this embodiment, the gain adjustment module 110 can output at least two reference voltage levels based on the level control signal. When the reference voltage switches from a higher voltage level to a lower voltage level, the auxiliary discharge module 120 discharges the charge storage module, increasing the rate of decrease of the reference voltage and thus shortening the establishment time of the reference voltage. Furthermore, after the reference voltage switches to a lower voltage level, the discharge to the charge storage module stops; that is, after the reference voltage switches to a lower voltage level, the auxiliary discharge module 120 no longer affects the charge storage module.

[0036] In some implementations, see Figure 2 The gain adjustment module 110 includes an output branch 111, which is used to connect to the charge storage module.

[0037] When the reference voltage switches from a higher voltage level to a lower voltage level, the reference voltage drops very slowly due to the voltage regulation characteristics of the charge storage module, resulting in a long settling time. The auxiliary discharge module 120 may include an auxiliary voltage generation branch 121, a first comparison unit 122, and a discharge branch 123. The auxiliary voltage generation branch 121 mirrors the current of the output branch 111, generating an auxiliary voltage based on the current. When the reference voltage is the target voltage, the auxiliary voltage is greater than the reference voltage, causing the auxiliary discharge module 120 to not perform auxiliary discharge and remain in a non-discharge state. The first comparison unit 122 compares the reference voltage and the auxiliary voltage. When the reference voltage is less than the auxiliary voltage, the first comparison unit 122 outputs a first level; when the reference voltage is greater than the auxiliary voltage, the first comparison unit 122 outputs a second level. When the first comparison unit 122 outputs the first level, the discharge branch 123 discharges the charge storage module; when the first comparison unit 122 outputs the second level, the discharge branch 123 stops discharging the charge storage module.

[0038] The first comparison unit 122 may include a comparator or a module with voltage comparison function. The output branch 111 outputs a reference voltage. The first and second voltage levels can be either high or low. When the first voltage level is high, the second voltage level is low; when the first voltage level is low, the second voltage level is high.

[0039] In this embodiment, during the process of switching the reference voltage from a higher voltage level to a lower voltage level, when the reference voltage is greater than the auxiliary voltage, the discharge branch 123 discharges the charge storage module, increasing the rate of decrease of the reference voltage and thus shortening the establishment time of the reference voltage; when the reference voltage is less than the auxiliary voltage, the discharge branch 123 stops discharging the charge storage module and no longer affects the charge storage module.

[0040] In some other implementations, the rate of decrease of the reference voltage can be increased by increasing the discharge current, thereby shortening the settling time of the reference voltage. This increase in discharge current can be achieved either by directly pulling down the voltage of the charge storage module via a switch, or by reducing the resistance of the discharge circuit in the charge storage module.

[0041] As one implementation method, see Figure 3 The discharge branch 123 includes a first switching unit 1231, which is connected in parallel with the charge storage module. Specifically, when the first comparison unit 122 outputs a first level, the first switching unit 1231 is turned on to discharge the charge storage module; when the first comparison unit 122 outputs a second level, the first switching unit 1231 is turned off to stop discharging the charge storage module.

[0042] The first switching unit 1231 may include one or more switches. Switches include, but are not limited to, transistors, field-effect transistors, etc. Field-effect transistors may be MOS (metal-oxide-semiconductor) transistors or other types of field-effect transistors; MOS transistors may be NMOS, PMOS, or complementary transmission gate switches.

[0043] In this embodiment, during the process of switching the reference voltage from a higher voltage level to a lower voltage level, when the first comparison unit 122 outputs a first level, the first switching unit 1231 turns on the voltage of the pull-down charge storage module, increases the discharge current of the charge storage module, and thus increases the rate of decrease of the reference voltage.

[0044] In other implementations, see Figure 4 The gain adjustment module 110 includes a second comparison unit 112, a feedback unit 113, and a third switching unit 114. The second comparison unit 112 includes a first input terminal, a second input terminal, and an output terminal. The first input terminal of the second comparison unit 112 is used to receive a reference voltage, and the output terminal is connected to the control terminal of the output branch 111. One end of the feedback unit 113 is connected to the first end of the output branch 111. The second end of the output branch 111 is connected to the power supply terminal, and the third end is its control terminal.

[0045] One end of the third switching unit 114 is connected to the other end of the feedback unit 113, and the other end is connected to the second input terminal of the second comparison unit 112. The third switching unit 114 includes at least two gear switches, which are turned on or off based on a gear control signal.

[0046] The second input terminal of the second comparison unit 112 receives feedback voltages for at least two gear positions from the feedback unit 113 based on the on / off result of the gear switch. The second comparison unit 112 compares the reference voltage with the feedback voltage to control the output branch 111 to output reference voltages for at least two gear positions that are proportional to the reference voltage.

[0047] In one implementation, the second comparison unit 112 includes one or more comparators.

[0048] In some other implementations, see Figure 4 The output branch 111 includes a fourth switching unit 1111. The first end of the fourth switching unit 1111 is connected to the feedback unit 113, the second end is connected to the power supply terminal, and the third end (i.e., the control terminal) is connected to the output terminal of the second comparison unit 112. The first end of the output branch 111 can be the first end of the fourth switching unit 1111.

[0049] The fourth switching unit 1111 may include one or more switches. Switches include, but are not limited to, transistors, field-effect transistors, etc. Field-effect transistors may be MOS (metal-oxide-semiconductor) transistors or other types of field-effect transistors; MOS transistors may be NMOS transistors, PMOS transistors, or complementary transmission gate switches.

[0050] In some other embodiments, the feedback unit 113 includes at least three first resistors connected in series and at least two feedback voltage terminals, with the feedback voltage terminals located between any two adjacent first resistors. The first ends of the at least three first resistors connected in series are connected to the first end of the output branch 111; each gear switch is correspondingly connected to one feedback voltage terminal.

[0051] In some other embodiments, the charge storage module includes one or more capacitors.

[0052] As an example, see Figure 5 The auxiliary voltage generating branch 121 includes a MOSFET 1211 and series resistors, which may include one or more resistors. In this example, the series resistors include resistors 1212, 1213, and 1214. The first terminal of the series connection of resistors 1212, 1213, and 1214 is connected to the first terminal of the MOSFET 1211, and the second terminal of the series connection of resistors 1212, 1213, and 1214 is grounded. The second terminal of the MOSFET 1211 is connected to the power supply terminal VDD, and the third terminal is connected to the fourth switching unit 1111. The MOSFET 1211 and the fourth switching unit 1111 form a basic current mirror. The MOSFET 1211 is used to mirror the current of the fourth switching unit 1111, and the resistors 1212, 1213, and 1214 are used to generate an auxiliary voltage based on the current. The first terminal of the series connection of resistors 1212, 1213, and 1214 outputs the auxiliary voltage. The first comparison unit 122 includes a comparator 1221, and the first switching unit 1231 includes a MOSFET 12311. The first input terminal of the comparator 1221 is connected to the first terminal of the MOSFET 1211, the second input terminal of the comparator 1221 is connected to the first terminal of the output branch 111, and the output terminal of the comparator 1221 is connected to the third terminal of the MOSFET 12311. The first and second terminals of the MOSFET 12311 are connected in parallel to the charge storage module, and the second terminal of the MOSFET 12311 is grounded.

[0053] In this circuit, MOSFET 1211 can be a PMOS transistor, and MOSFET 12311 can be an NMOS transistor. The first terminal of MOSFETs 1211 and 12311 can be the drain, the second terminal can be the source, and the third terminal can be the gate. The first input terminal of comparator 1221 can be an inverting input terminal, and the second input terminal can be a non-inverting input terminal. The first voltage level can be low, and the second voltage level can be high.

[0054] In this example, when the reference voltage is greater than the auxiliary voltage, comparator 1221 outputs a high level, MOSFET 12311 is turned on, and MOSFET 12311 forms a discharge circuit with the charge storage module, increasing the discharge current of the charge storage module. This allows the charge storage module to discharge quickly and shortens the setup time of the reference voltage. When the reference voltage is less than the auxiliary voltage, comparator 1221 outputs a low level, MOSFET 12311 is turned off, and MOSFET 12311 no longer forms a discharge circuit with the charge storage module.

[0055] See Figure 5 The second comparison unit 112 includes comparators 1121 and 1122; the fourth switching unit 1111 includes a MOSFET 11111; the feedback unit 113 includes resistors 1131, 1132, and 1133 connected in series, a first feedback voltage terminal, and a second feedback voltage terminal; the third switching unit 114 includes gear switches 1141 and 1142; and the charge storage module includes a capacitor CL.

[0056] The first input terminal of comparator 1121 receives a reference voltage, and its output terminal is connected to the second input terminal of comparator 1122. The first input terminal of comparator 1122 is connected to its output terminal, and the output terminal of comparator 1122 is connected to the third terminal of MOSFET 11111. The second terminal of MOSFET 11111 is connected to the power supply terminal VDD, and its first terminal is connected to one end of resistor 1131. One end of resistor 1132 is connected to the other end of resistor 1131, and the other end of resistor 1132 is connected to one end of resistor 1133. The other end of resistor 1133 is grounded. The first feedback voltage terminal is located between resistors 1131 and 1132, and the second feedback voltage terminal is located between resistors 1132 and 1133. The first feedback voltage terminal is connected to one end of gear switch 1141, and the other end of gear switch 1141 is connected to the second input terminal of comparator 1121. The second feedback voltage terminal is connected to one end of gear switch 1142, and the other end of gear switch 1142 is connected to the second input terminal of comparator 1121. One end of capacitor CL is connected to the first terminal of MOSFET 11111, and the other end is grounded.

[0057] In this example, the first input terminals of comparators 1121 and 1122 can be inverting input terminals, and the second input terminal can be non-inverting input terminals. The MOSFET 11111 can be a PMOS transistor, with its first terminal being the drain, its second terminal being the source, and its third terminal being the gate. The gear control signal can be a high-level signal, a low-level signal, or a pulse signal. In this example, when the gear control signal is high, the corresponding gear switch is turned on; when the gear control signal is low, the corresponding gear switch is turned off.

[0058] See Figure 5Let the reference voltage be VBG, the reference voltage be VREF, the auxiliary voltage be VREF1, the first feedback voltage terminal be VFB1, the second feedback voltage terminal be VFB2, the output voltage of comparator 1121 be VO1, and the output voltage of comparator 1122 be VP. Set the resistance of resistor 1131 to R1, the resistance of resistor 1132 to R2, and the resistance of resistor 1133 to R3. Set the current flowing through MOSFET 11111 to I. MP .

[0059] In this example, MOSFET 1211 mirrors the current of MOSFET 11111. By adjusting the width-to-length ratio of MOSFET 11111 and MOSFET 1211, the current of MOSFET 1211 can be set as a fraction of the current of MOSFET 11111. Resistors 1212, 1213, and 1214 are set to be M times the voltages of resistors 1131, 1132, and 1133, respectively. And the voltage VREF = I MP [(R1+R2+R3)||RL]. By setting... This ensures that VREF1 > VREF under normal circuit conditions, keeping the auxiliary discharge module off and not affecting normal circuit operation.

[0060] When gear switch 1141 is on and gear switch 1142 is off, due to the virtual short characteristic of the input terminal of comparator 1121, VFB1 = VBG can be obtained. Then, according to the principle of resistor voltage division, the following can be obtained: When gear switch 1142 is on and gear switch 1141 is off, due to the virtual short characteristic of the input terminal of comparator 1121, VFB2 = VBG can be obtained. Then, according to the principle of resistor voltage division, we can obtain... That is, the voltage value VREF of the output reference voltage can be adjusted by using the selector switch 1141 and the selector switch 1142.

[0061] When the state of gear switch 1141 being on and gear switch 1142 being off is switched to the state of gear switch 1142 being on and gear switch 1141 being off, initially VBG = VFB1 > VFB2. The output voltage value VO1 of comparator 1121 will decrease. The decrease in VO1 will cause VP to decrease through comparator 1122, increasing the current through MOSFET 11111, and raising VREF until VBG = VFB2 is satisfied, at which point VREF reaches the target voltage value, which is VREF = VFB2 * (R1 + R2 + R3) / R3. During the VREF rise process, because MOSFET 11111 can provide a large current to charge capacitor CL, the VREF rise process is established very quickly.

[0062] See Figure 6 When switching from the state where the gear switch 1142 is on and the gear switch 1141 is off to the state where the gear switch 1141 is on and the gear switch 1142 is off, during the stage from t1 to t2, the initial VBG = VFB2 < VFB1, the output VO1 of the comparator 1121 will increase, thereby increasing VP. When the voltage difference between VDD and VP is less than the conduction voltage of the MOS transistor 11111, the MOS transistor 11111 is turned off, and the capacitor CL discharges through the load resistor RL and the feedback resistors 1131 to 1133, causing the VREF voltage to decrease. During the process of the VREF voltage decreasing, the discharge current of the capacitor CL is where is the static current of the MOS transistor 11111, which is usually small, and the load resistor RL is usually large, resulting in a very small discharge current of the capacitor CL and a very slow decrease in the VREF voltage. The MOS transistor 1211 mirrors the current of the MOS transistor 11111, and when the MOS transistor 11111 is turned off, the MOS transistor 1211 will also be turned off. The VREF1 point discharges through the resistors 1212, 1213, and 1214. Since there is no large capacitor in the auxiliary voltage generation branch, the VREF1 can decrease quickly. When VREF1 decreases to less than VREF, the output voltage value VCTRL of the comparator 1221 jumps to a high level, turning on the MOS transistor 12311, increasing the current in the VREF discharge loop, and accelerating the discharge of VREF, that is, accelerating the establishment of VREF. Until VBG = VFB1 is satisfied and VREF reaches the target voltage value, the target voltage value at this time is VREF = VFB1 * (R1 + R2 + R3) / (R2 + R3). When VREF reaches the target voltage value, the capacitor CL stops discharging.

[0063] Since VREF decreases, VFB1 decreases, and VP begins to decrease. At the moment t4, when the voltage difference between VDD and VP is greater than the conduction voltage of the MOS transistor 11111, the MOS transistor 11111 is turned on. The current in the resistors 1131, 1132, and 1133 is provided by the MOS transistor 11111. Assuming that the MOS transistor 11111 is turned on at the moment t4, after the moment t4, due to the setting of the current ratio N and the resistance ratio M, the relationship is obtained, that is, VREF1 > VREF, and the output VCTRL of the comparator 1221 jumps to a low level to turn off the MOS transistor 12311 to ensure that it will not affect the normal operation of the gain adjustment module 110. That is, the present invention can quickly switch the output voltage gear of the gain adjustment module 110 through the auxiliary discharge module 120, and the auxiliary discharge module 120 will not affect the normal operation of the gain adjustment module 110.

[0064] In some other embodiments, refer to Figure 7The discharge branch 123 includes a first resistor unit 1232 and a second switch unit 1233, which are connected in series and then connected in parallel with the charge storage module. Specifically, when the first comparison unit 122 outputs a first level, the second switch unit 1233 is turned on, and the first resistor unit 1232 discharges to the charge storage module; when the first comparison unit 122 outputs a second level, the second switch unit 1233 is turned off, and the first resistor unit 1232 stops discharging to the charge storage module.

[0065] In this embodiment, during the process of switching the reference voltage from a higher voltage level to a lower voltage level, when the first comparison unit 122 outputs a first level, the second switching unit 1233 is turned on to reduce the resistance of the discharge circuit of the charge storage module, increase the discharge current of the charge storage module, and thus increase the rate of decrease of the reference voltage.

[0066] The first resistor unit 1232 includes one or more resistors, and the second switch unit 1233 includes one or more switches.

[0067] In one implementation, the first resistor unit 1232 includes a resistor, and the second switch unit 1233 includes a switch. The resistor and the switch are connected in series and then in parallel to the feedback unit 113.

[0068] In another implementation, the first resistor unit 1232 includes at least three second resistors connected in series. The second switch unit 1233 includes at least three first switches connected in series with each of the second resistors, with each first switch connected in series with a second resistor and then connected in parallel with another first resistor. When the first comparison unit 122 outputs a first level, all the first switches are turned on, and the second resistors discharge to the charge storage module; when the first comparison unit 122 outputs a second level, all the first switches are turned off, and the second resistors stop discharging to the charge storage module. The first switches can be multiplexed switches.

[0069] As an example, see Figure 8 The first resistor unit 1232 includes three second resistors connected in series, namely resistors 12321, 12322, and 12323. The second switch unit 1233 includes three first switches, namely switches 12331, 12332, and 12333. Resistor 12321 is connected in series with switch 12331 and then in parallel with resistor 1131. Resistor 12322 is connected in series with switch 12332 and then in parallel with resistor 1132. Resistor 12323 is connected in series with switch 12333 and then in parallel with resistor 1133. The control terminals of switches 12331, 12332, and 12333 are connected to the output terminal of comparator 1221.

[0070] Among them, switch 12331, switch 12332, and switch 12333 can be arranged in a multiplexer.

[0071] Set the resistance value of resistor 12321 as R4, the resistance value of resistor 12322 as R5, and the resistance value of resistor 12323 as R6.

[0072] When the state of gear switch 1142 being turned on and gear switch 1141 being turned off switches to the state of gear switch 1141 being turned on and gear switch 1142 being turned off, the output voltage value VCTRL of comparator 1221 jumps to a high level, turning on switch 12331, switch 12332, and switch 12333, and connecting resistor 12321 - resistor 12323 to the discharge circuit of capacitor CL. At this time, the discharge current of capacitor CL can be By setting the resistance values of resistor 12321 - resistor 12323, the resistance of the discharge circuit of capacitor CL can be reduced, the discharge current can be increased, and the establishment of VREF can be accelerated. For example, set Since the value of load resistor RL is usually large, resistor 12321 - resistor 12323 can increase the discharge speed of capacitor CL by about K times, that is, increase the establishment speed of VREF by about K times.

[0073] When VREF is established, VREF < VREF1, the output voltage value VCTRL of comparator 1221 is at a low level, switch 12331 - switch 12333 are closed, and resistor 12321 - resistor 12323 are disconnected from the discharge circuit of capacitor CL, that is, the auxiliary discharge module does not additionally increase the static current of output branch 111 when gain adjustment module 110 is working normally.

[0074] The embodiment of the present application also provides a control method for a reference voltage generation circuit. The reference voltage generation circuit includes a gain adjustment module, and the gain adjustment module is used to adjust the reference voltage based on a gear control signal to output at least two gears of reference voltage proportional to the reference voltage. The at least two gears of reference voltage include a first gear voltage and a second gear voltage. This method is applied to an auxiliary discharge module and includes:

[0075] During the process of the reference voltage switching from the first gear voltage to the second gear voltage, discharge the charge storage module; after the reference voltage switches from the first gear voltage to the second gear voltage, stop discharging the charge storage module. Among them, the first gear voltage is greater than the second gear voltage. In some embodiments, the gain adjustment module includes an output branch, and the output branch is used to connect to the charge storage module. The control method includes:

[0076] Mirror the current of the output branch, and generate an auxiliary voltage based on the current. Among them, when the reference voltage is the target voltage, the auxiliary voltage is greater than the reference voltage;

[0077] The reference voltage and the auxiliary voltage are compared. When the reference voltage is less than the auxiliary voltage, the comparison output is at the first level; when the reference voltage is greater than the auxiliary voltage, the comparison output is at the second level.

[0078] The charge storage module is discharged when the comparison output is at the first level; the discharge of the charge storage module is stopped when the comparison output is at the second level.

[0079] In other embodiments, the auxiliary discharge module includes a discharge branch, which includes a first switching unit connected in parallel with the charge storage module. When the comparison output is at a first level, the first switching unit is turned on to discharge the charge storage module; when the comparison output is at a second level, the first switching unit is turned off to stop discharging the charge storage module.

[0080] In some other embodiments, the discharge branch includes a first resistor unit and a second switch unit, which are connected in series and then connected in parallel with the charge storage module. When the comparison output is at a first level, the second switch unit is turned on, and the first resistor unit discharges to the charge storage module; when the comparison output is at a second level, the second switch unit is turned off, and the first resistor unit stops discharging to the charge storage module.

[0081] In some embodiments, the gain adjustment module includes a second comparison unit, a feedback unit, and a third switching unit. The second comparison unit includes a first input terminal, a second input terminal, and an output terminal; the first input terminal receives a reference voltage, and the output terminal is connected to the control terminal of the output branch. One end of the feedback unit is connected to the first terminal of the output branch. One end of the third switching unit is connected to the other end of the feedback unit, and the other end is connected to the second input terminal of the second comparison unit; the third switching unit includes at least two position switches; the position switches are turned on or off based on a position control signal. The second input terminal of the second comparison unit receives feedback voltages of at least two positions from the feedback unit based on the on / off result of the position switches. The second comparison unit compares the reference voltage with the feedback voltage to control the output branch to output a reference voltage proportional to the reference voltage at least two positions.

[0082] In some other embodiments, the output branch includes a fourth switching unit, with a first end connected to the feedback unit, a second end connected to the power supply, and a third end connected to the output of the second comparison unit.

[0083] In some other embodiments, the feedback unit includes at least three first resistors connected in series and at least two feedback voltage terminals, with the feedback voltage terminals located between any two adjacent first resistors. The first ends of the at least three first resistors connected in series are connected to the first end of the output branch, and each gear switch is connected to a corresponding feedback voltage terminal.

[0084] In some embodiments, the first resistor unit includes at least three second resistors connected in series. The second switching unit includes at least three first switches connected in series with each of the second resistors, with each first switch connected in series with a second resistor and then connected in parallel with another first resistor. When the comparison output is at a first level, all the first switches are turned on, and the second resistors discharge to the charge storage module; when the comparison output is at a second level, all the first switches are turned off, and the second resistors stop discharging to the charge storage module.

[0085] This application embodiment also provides a chip, which includes the aforementioned reference voltage generation circuit 100. The chip, also known as an integrated circuit (IC), can be, but is not limited to, a System-on-Chip (SOC) chip or a System-in-Package (SIP) chip. During the process of switching the reference voltage from a higher voltage level to a lower voltage level, the chip discharges the charge storage module, increasing the rate of reference voltage decrease and shortening the reference voltage settling time; after the reference voltage switches from a higher voltage level to a lower voltage level, the discharge to the charge storage module stops.

[0086] This application also provides an electronic device, which includes a device body and a chip as described above disposed within the device body. The electronic device may be, but is not limited to, a weight scale, body fat scale, nutrition scale, infrared electronic thermometer, pulse oximeter, body composition analyzer, power bank, wireless charger, fast charger, car charger, adapter, display, USB (Universal Serial Bus) docking station, stylus, true wireless earphones, car infotainment screen, automobile, smart wearable device, mobile terminal, and smart home device. Smart wearable devices include, but are not limited to, smartwatches, smart bracelets, and neck massagers. Mobile terminals include, but are not limited to, smartphones, laptops, tablets, and POS (point of sales terminal) machines. Smart home devices include, but are not limited to, smart sockets, smart rice cookers, smart robot vacuums, and smart lights. During the process of switching the reference voltage from a higher voltage level to a lower voltage level, the electronic device discharges the charge storage module to increase the rate of reference voltage decrease and shorten the reference voltage settling time; after the reference voltage switches from a higher voltage level to a lower voltage level, the discharge of the charge storage module stops.

[0087] The above are merely preferred embodiments of this application and are not intended to limit this application in any way. Although this application has disclosed preferred embodiments as above, it is not intended to limit this application. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the technical solution of this application. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of this application without departing from the scope of the technical solution of this application shall still fall within the scope of the technical solution of this application.

Claims

1. A reference voltage generation circuit, characterized in that, include: A gain adjustment module is used to adjust the reference voltage based on a range control signal to output a reference voltage at least two ranges that are proportional to the reference voltage. The reference voltage at least two levels includes a first level voltage and a second level voltage; An auxiliary discharge module is used to connect to the charge storage module and discharge the charge storage module during the process of the reference voltage switching from the first voltage level to the second voltage level; after the reference voltage switches from the first voltage level to the second voltage level, the discharge of the charge storage module is stopped; wherein, the first voltage level is greater than the second voltage level. The gain adjustment module includes: An output branch is used to connect to the charge storage module; The auxiliary discharge module includes: An auxiliary voltage generating branch is used to mirror the current of the output branch and generate an auxiliary voltage based on the current; A first comparison unit is used to compare the reference voltage and the auxiliary voltage, and outputs a first level when the reference voltage is less than the auxiliary voltage, and outputs a second level when the reference voltage is greater than the auxiliary voltage. The discharge branch discharges the charge storage module when the first comparison unit outputs a first level, and stops discharging the charge storage module when the first comparison unit outputs a second level. The gain adjustment module includes: The second comparison unit includes a first input terminal, a second input terminal, and an output terminal; the first input terminal is used to receive a reference voltage, and the output terminal is connected to the control terminal of the output branch; A feedback unit, one end of which is connected to the first end of the output branch; A third switching unit, one end of which is connected to the other end of the feedback unit and the other end of which is connected to the second input terminal of the second comparison unit; the third switching unit includes at least two gear switches; the gear switches are turned on or off based on the gear control signal; The second input terminal of the second comparison unit receives feedback voltages for at least two gear positions from the feedback unit based on the on / off result of the gear switch; the second comparison unit compares the reference voltage with the feedback voltage to control the output branch to output reference voltages for at least two gear positions that are proportional to the reference voltage.

2. The reference voltage generating circuit as described in claim 1, characterized in that, The discharge branch includes: The first switching unit is used to be connected in parallel with the charge storage module; Specifically, when the first comparison unit outputs a first level, the first switch unit is turned on to discharge the charge storage module; when the first comparison unit outputs a second level, the first switch unit is turned off to stop discharging the charge storage module.

3. The reference voltage generating circuit as described in claim 1, characterized in that, The discharge branch includes: A first resistor unit and a second switch unit are connected in series and then connected in parallel with the charge storage module. Specifically, when the first comparison unit outputs a first level, the second switch unit is turned on, and the first resistor unit discharges to the charge storage module; when the first comparison unit outputs a second level, the second switch unit is turned off, and the first resistor unit stops discharging to the charge storage module.

4. The reference voltage generating circuit as described in claim 1, characterized in that, The output branch includes: The fourth switching unit has a first end connected to the feedback unit, a second end connected to the power supply, and a third end connected to the output of the second comparison unit.

5. The reference voltage generating circuit as described in claim 3, characterized in that, The feedback unit includes: At least three first resistors connected in series; At least two feedback voltage terminals, wherein the feedback voltage terminals are located between any two adjacent first resistors; Wherein, the first end of the at least three series-connected first resistors is connected to the first end of the output branch; each of the gear switches is connected to a corresponding feedback voltage terminal.

6. The reference voltage generating circuit as described in claim 5, characterized in that, The first resistor unit includes at least three second resistors connected in series; The second switching unit includes at least three first switches connected in series with the second resistor in a one-to-one correspondence. Each first switch is connected in series with a second resistor and then in parallel with a first resistor. Specifically, when the first comparison unit outputs a first level, all the first switches are turned on, and the second resistor discharges to the charge storage module; when the first comparison unit outputs a second level, all the first switches are turned off, and the second resistor stops discharging to the charge storage module.

7. A control method for a reference voltage generating circuit, the reference voltage generating circuit including a gain adjustment module, the gain adjustment module being used to adjust a reference voltage based on a level control signal to output a reference voltage at least two levels proportional to the reference voltage; The reference voltage at least two levels includes a first level voltage and a second level voltage; characterized in that, The control method includes: During the process of switching the reference voltage from the first voltage level to the second voltage level, the charge storage module is discharged; after the reference voltage switches from the first voltage level to the second voltage level, the discharge of the charge storage module stops; wherein, the first voltage level is greater than the second voltage level. The gain adjustment module includes an output branch for connection to the charge storage module. The control method includes: mirroring the current of the output branch and generating an auxiliary voltage based on the current; wherein, when the reference voltage is a target voltage, the auxiliary voltage is greater than the reference voltage; comparing the reference voltage and the auxiliary voltage, and when the reference voltage is less than the auxiliary voltage, setting the comparison output to a first level; when the reference voltage is greater than the auxiliary voltage, setting the comparison output to a second level; discharging the charge storage module when the comparison output is at the first level; and stopping the discharge of the charge storage module when the comparison output is at the second level. The gain adjustment module includes: The second comparison unit includes a first input terminal, a second input terminal, and an output terminal; the first input terminal is used to receive a reference voltage, and the output terminal is connected to the control terminal of the output branch; A feedback unit, one end of which is connected to the first end of the output branch; A third switching unit, one end of which is connected to the other end of the feedback unit and the other end of which is connected to the second input terminal of the second comparison unit; the third switching unit includes at least two gear switches; the gear switches are turned on or off based on the gear control signal; The second input terminal of the second comparison unit receives feedback voltages for at least two gear positions from the feedback unit based on the on / off result of the gear switch; the second comparison unit compares the reference voltage with the feedback voltage to control the output branch to output reference voltages for at least two gear positions that are proportional to the reference voltage.

8. A chip, characterized in that, The reference voltage generating circuit includes any one of claims 1 to 6.

9. An electronic device, characterized in that, It includes a device body and a chip as described in claim 8 disposed on the device body.

Images