Controller and method for controlling a voltage converter

Abstract

A controller and method for controlling a voltage converter are provided. The controller is coupled with an adapter that provides power to a system and a battery, and the voltage converter receives an input voltage provided by the adapter and generates a real-time charging current for the battery and a real-time battery voltage. The controller includes a compensation module, a response adjustment module, and a driving module. The compensation module compares the real-time charging current with a preset charging current to generate a first comparison result, compares the real-time battery voltage with a preset battery voltage to generate a second comparison result, compares a real-time adapter current of the adapter with a preset adapter current to generate a third comparison result, and generates a compensation voltage based on the first, second, and third comparison results. The response adjustment module sets a value of the compensation voltage to a preset voltage value if the real-time adapter current is greater than the preset adapter current. The driving module generates a first switching signal and a second switching signal based on the compensation voltage to control an upper switch and a lower switch of the voltage converter, respectively.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of controller, and in particular to a controller and method for voltage converter. BACKGROUND

[0002] Figure 1 A power supply circuit 100 is shown, which includes a controller 110 and a voltage converter 120. The power supply circuit 100 receives power from an adapter 102 and supplies power to a system 180 (such as an electronic device) and a battery 160. The adapter 102 provides a portion of the power directly to the system 180 and another portion of the power is used to charge the battery 160 through the voltage converter 120 (such as a buck converter). The controller 110 internally generates a pulse width modulation signal and generates signals HDR and LDR according to the pulse width modulation signal to control the upper switch Q1 and the lower switch Q2 of the voltage converter 120, respectively. During the operation of the power supply circuit 100, the power demand of the system 180 sometimes exceeds the power provided by the adapter 102, so the battery 160 needs to supplement the power demand of the system 180 in the shortest possible time, otherwise it may cause the system 180 to degrade in performance or even crash. In this case, the power supply circuit 100 enters a parallel power supply mode, in which the controller 110 controls the voltage converter 120 to perform reverse step-up on the voltage of the battery 160, and the power provided by the battery 160 and the power provided by the adapter 102 together supply power to the system 180. In the traditional control method, after entering the parallel power supply mode, in order to control the voltage converter 120, the duty cycle of the pulse width modulation signal generated by the controller 110 gradually decreases from the initial value 100% to the duty cycle required for the stable operation of the system 180 (the duty cycle of the corresponding LDR signal gradually increases from 0), which takes a long time, and when the system 180 needs a large current, the controller 110 may not be able to respond in time. SUMMARY

[0003] The present application provides a controller for controlling a voltage converter. The controller is coupled with an adapter which provides power for a system and a battery, and the voltage converter receives an input voltage provided by the adapter and generates a real-time charging current for the battery and a real-time battery voltage. The controller includes a compensation module, a response adjustment module and a driving module. The compensation module compares the real-time charging current with a preset charging current to generate a first comparison result, compares the real-time battery voltage with a preset battery voltage to generate a second comparison result, compares a real-time adapter current of the adapter with a preset adapter current to generate a third comparison result, and generates a compensation voltage according to the first comparison result, the second comparison result and the third comparison result. The response adjustment module sets a value of the compensation voltage as a preset voltage value if the real-time adapter current is greater than the preset adapter current. The driving module generates a first switch signal and a second switch signal according to the compensation voltage to control an upper switch and a lower switch of the voltage converter respectively.

[0004] The present application also provides a method for controlling a voltage converter which receives an input voltage from an adapter and provides a real-time charging current for a battery and a real-time battery voltage. The method includes the steps of comparing the real-time charging current with a preset charging current to generate a first comparison result, comparing the real-time battery voltage with a preset battery voltage to generate a second comparison result, comparing a real-time adapter current of the adapter with a preset adapter current to generate a third comparison result, generating a compensation voltage according to the first comparison result, the second comparison result and the third comparison result, generating a preset voltage value according to the input voltage and the real-time battery voltage, setting a value of the compensation voltage as the preset voltage value if the real-time adapter current is greater than the preset adapter current, and generating a first switch signal and a second switch signal according to the compensation voltage to control an upper switch and a lower switch of the voltage converter respectively.

[0005] As mentioned above, the present application discloses a controller for controlling a voltage converter and a method for controlling a voltage converter. When power required by a system is greater than power provided by an adapter, the controller sets a value of a compensation voltage as a preset voltage value calculated according to an input voltage and a real-time battery voltage, so that the system can be quickly stabilized. BRIEF DESCRIPTION OF DRAWINGS

[0006] The objectives, specific features and advantages of the present application will become further apparent from the following description of some embodiments of the present application given for the purpose of illustration only, and with reference to the accompanying drawings.

[0007] Figure 1 A conventional power supply circuit is shown;

[0008] Figure 2 A power supply circuit according to an embodiment of the present application is shown;

[0009] Figure 3FIG. 1 illustrates a circuit diagram of a controller according to one embodiment of the present application;

[0010] Figure 4 FIG. 2 illustrates a timing diagram of a controller according to one embodiment of the present application;

[0011] Figure 5 FIG. 3 illustrates a circuit diagram of a prediction module of a controller according to one embodiment of the present application;

[0012] Figure 6 FIG. 4 illustrates a circuit diagram of a prediction module of a controller according to another embodiment of the present application;

[0013] Figure 7 FIG. 5 illustrates a flow chart of a method for controlling a voltage converter according to one embodiment of the present application. DETAILED DESCRIPTION

[0014] Embodiments of the present application will be described in detail herein below. Although the present application is illustrated and described herein through implementation with these embodiments, it is understood that the present application is not limited to these embodiments alone. Rather, the present application is capable of use in various other embodiments and with several modifications as will be readily appreciated by those of skill in the art. Such embodiments and modifications are intended to fall within the scope of the present application.

[0015] All alternatives, modifications, and equivalents falling within the spirit and scope of the appended claims are encompassed by the present application.

[0016] In addition, numerous specific details are given in the following description in order to provide a thorough understanding of the present application. Those skilled in the art will understand, however, that the present application can be practiced without these specific details. In other instances, well-known methods, procedures, components, and circuits have not been described in detail in order to avoid obscuring the present application.

[0017] Figure 2 FIG. 1 illustrates a circuit diagram of a controller according to one embodiment of the present application;

[0018] The controller 210 includes a compensation module 206, a response adjustment module 202, and a drive module 204. The compensation module 206 compares the real-time charging current IBATT with the preset charging current ISET to generate a first comparison result, compares the real-time battery voltage VBATT with the preset battery voltage VSET to generate a second comparison result, compares the real-time adapter current IAD of the adapter 102 with the preset adapter current IADSET to generate a third comparison result, and generates a compensation voltage VCOMP according to the first comparison result, the second comparison result, and the third comparison result. As shown in FIG. 2, the controller 210 detects the real-time adapter current IAD by using a resistor Rl, and detects the real-time charging current IBATT by using a resistor R2. Specifically, the controller 210 receives a voltage signal VIN from one end of the resistor Rl, and receives a voltage signal IACM from the other end of the resistor Rl. The voltage signal VIN is the input voltage provided by the adapter 102, and the difference between the voltage signal VIN and the voltage signal IACM indicates the real-time adapter current IAD. The controller 210 receives a voltage signal ICHP from one end of the resistor R2, and receives a voltage signal VBATT from the other end of the resistor R2. The voltage signal VBATT is the real-time battery voltage, and the difference between the voltage signal ICHP and the voltage signal VBATT indicates the real-time charging current IBATT. Figure 2

[0019] If the controller 210 monitors that the real-time adapter current IAD is greater than the preset adapter current IADSET, i.e., determines that the power required by the system 180 is greater than the power provided by the adapter 102, the power supply circuit 200 enters the parallel power supply mode, in which the controller 210 controls the voltage converter 120 to reversely boost the voltage provided by the battery 160 to the size of the input voltage VIN provided by the adapter 102, and the power provided by the battery 160 and the power provided by the adapter 102 jointly supply power to the system 180. The response adjustment module 202 sets the value of the compensation voltage VCOMP to a preset voltage value VCSET, wherein the preset voltage value VCSET is generated according to the input voltage VIN and the real-time battery voltage VBATT. The drive module 204 generates a first switch signal HDR and a second switch signal LDR according to the compensation voltage VCOMP to control the upper side switch Ql and the lower side switch Q2 of the voltage converter 120, respectively.

[0020] Figure 3 ​The diagram shows a circuit diagram of a controller 210 according to an embodiment of the present invention. The controller 210 includes a compensation module 206, a response adjustment module 202, and a drive module 204. The compensation module 206 includes a first operational amplifier EA1, a second operational amplifier EA2, a third operational amplifier EA3, a fourth operational amplifier CSA1, and a fifth operational amplifier CSA2. The fourth operational amplifier CSA1 compares a voltage signal ICHP and a voltage signal VBATT and generates an IBATT signal representing the real-time charging current. The fifth operational amplifier CSA2 compares a voltage signal VIN and a voltage signal IACM and generates an IAD signal representing the real-time adapter current. The first operational amplifier EA1 compares the real-time charging current IBATT and a preset charging current ISET and generates a first comparison result. The second operational amplifier EA2 compares the real-time battery voltage VBATT and a preset battery voltage VSET and generates a second comparison result. The third operational amplifier EA3 compares the real-time adapter current IAD and a preset adapter current IADSET and generates a third comparison result. The compensation module 206 also includes a current source S1 for charging a capacitor C2. The voltage across capacitor C2 is the compensation voltage VCOMP, which is adjusted by the results of the first, second, and third comparisons mentioned above. Specifically, if the real-time charging current IBATT is less than the preset charging current ISET, the output of the first operational amplifier EA1 increases, and the current provided by the current source S1 charges capacitor C2, thus increasing the compensation voltage VCOMP. If the real-time charging current IBATT is greater than the preset charging current ISET, the output of the first operational amplifier EA1 decreases, and the first operational amplifier EA1 absorbs the current provided by the current source S1, thus decreasing the compensation voltage VCOMP. If the real-time battery voltage VBATT is less than the preset battery voltage VSET, the output of the first operational amplifier EA2 increases, and the current provided by the current source S1 charges capacitor C2, thus increasing the compensation voltage VCOMP. If the real-time battery voltage VBATT is greater than the preset battery voltage VSET, the output of the second operational amplifier EA2 decreases, and the second operational amplifier EA2 absorbs the current provided by the current source S1, thus decreasing the compensation voltage VCOMP. If the real-time adapter current IAD is less than the preset adapter current IADSET, the output of the third operational amplifier EA3 increases, the current provided by the current source S1 charges the capacitor C2, and the compensation voltage VCOMP increases; if the real-time adapter current IAD is greater than the preset adapter current IADSET, the output of the third operational amplifier EA3 decreases, the third operational amplifier EA3 absorbs the current provided by the current source S1, and the compensation voltage VCOMP decreases.

[0021] The drive module 204 includes a triangular wave generator 330, a first comparator COMP1, and a driver 211. The triangular wave generator 330 is used to generate a triangular wave signal VTR. Figure 4As shown, the peak value of the triangular wave signal VTR is V. P Valley value V V The peak-to-peak value is V R V R =V P -V V The first comparator COMP1 generates a pulse width modulation signal PWM1 based on the triangular wave signal VTR and the compensation voltage VCOMP. For example... Figure 3 As shown, the first input of the first comparator COMP1 receives a compensation voltage VCOMP, the second input receives a triangular wave signal VTR, and the output outputs a pulse width modulation signal PWM1. The first input of COMP1, the output of the first operational amplifier EA1, the output of the second operational amplifier EA2, the output of the third operational amplifier EA3, the current source S1, and the capacitor C2 are connected to a common node NC1. The driver 211 generates a first switching signal HDR and a second switching signal LDR based on the pulse width modulation signal PWM1. In one embodiment, the driver 211 includes a buffer 212 and an inverter 213.

[0022] like Figure 4 As shown, when the compensation voltage VCOMP is greater than the triangular wave signal VTR, the pulse width modulation signal PWM1 is at a high level; when the compensation voltage VCOMP is less than the triangular wave signal VTR, the pulse width modulation signal PWM1 is at a low level. The duty cycle D of the pulse width modulation signal PWM1 can be calculated according to the following equation:

[0023] D = (VCOMP - V) V ) / V R (1)

[0024] Based on the operating principle of voltage converter 120, in continuous conduction mode, the relationship between the input voltage (ignoring the voltage drop across resistor R1, i.e., the input voltage VIN provided by adapter 102) and the output voltage (ignoring the voltage drop across resistor R2, i.e., the real-time battery voltage VBATT) of voltage converter 120 is as follows:

[0025] VBATT=VIN×D (2)

[0026] According to equations (1) and (2), we can obtain:

[0027] VCOMP = V V +(VBATT×V R ) / VIN (3)

[0028] As can be seen from equation (3), when the power supply circuit 200 switches to parallel power supply mode, the compensation voltage VCOMP is set to V. V +(VBATT×VR VIN, the initial duty cycle of the pulse width modulation signal PWM1 required for the system 180 to operate stably can be set.

[0029] The response adjustment module 202 includes a prediction module 360 and a switch unit 303. The prediction module 360 generates a preset voltage value VCSET according to the input voltage VIN and the real-time battery voltage VBATT. The switch unit 303 is coupled between the compensation module 206 and the prediction module 360. If the real-time adapter current IAD is greater than the preset adapter current IADSET (i.e., the power required by the system 180 is greater than the power provided by the adapter 102), the power supply circuit 200 enters the parallel power supply mode, the prediction module 360 turns on the switch unit 303, so as to set the compensation voltage VCOMP to the preset voltage value VCSET, wherein the value of VCSET is obtained by equation (3), i.e., VCSET = V V +(VBATT x V R ) / VIN. Specifically, when the switch unit 303 is turned on, the capacitor C2 is rapidly charged by the second current source S2, and when the voltage on the capacitor (i.e., the compensation voltage VCOMP) reaches the preset voltage value VCSET, the prediction module 360 turns off the switch unit 303, thereby completing the setting of the compensation voltage VCOMP. After the switch unit 303 is turned off, the compensation voltage VCOMP is adjusted by the compensation module 206 according to the first comparison result, the second comparison result, and the third comparison result. In the conventional control method, after the power supply circuit 100 enters the parallel power supply mode, the value of VCOMP starts to gradually decrease from the maximum value (i.e., the peak value V P of the triangular wave signal VTR), and the duty cycle of the corresponding pulse width modulation signal PWM1 starts to gradually decrease from 100% to the duty cycle required for the system 180 to operate stably (i.e., the duty cycle of the LDR signal starts to gradually increase from 0), which requires a long time. However, in the controller 210 disclosed in the present application, the value of VCOMP is set to VCSET when the power supply circuit 200 enters the parallel power supply mode, and the duty cycle of the pulse width modulation signal PWM1 can meet the requirement for the system 180 to operate stably, so that the response speed of the system is improved.

[0030] Figure 5 FIG. 6 shows a circuit diagram of the prediction module 360 of the controller according to an embodiment of the present application. The prediction module 360 includes a calculation unit 361, an enabling unit 362, a second comparator 510, and an AND gate 512. The calculation unit 361 is configured to calculate the preset voltage value VCSET, and the second comparator 510 compares the compensation voltage VCOMP with the preset voltage value VCSET. The enabling unit 362 compares the preset adapter current IADSET with the real-time adapter current IAD to generate an enabling signal EN. In Figure 5In the embodiment, the enabling unit 362 includes a comparator 514. The AND gate 512 generates a switching signal CTR according to the output of the second comparator 510 and the enabling signal EN to control the switching unit 303. In Figure 5 In the example, the calculating unit 361 calculates the preset voltage value VCSET according to the equation VCSET = V V + (VBATT x V R ) / VIN by using the multipliers 502 and 506, the divider 504 and the adder 508, where V V is the valley value of the triangular wave signal VTR, VBATT is the real-time battery voltage, V R is the peak-to-peak value of the triangular wave signal VTR, and VIN is the input voltage.

[0031] In practical applications, the voltage value of the input voltage VIN is generally a fixed value. For applications of 3 or 4 batteries, the voltage value of VIN is generally a fixed 19V, and for applications of 2 batteries, the voltage value of VIN is generally a fixed 12V. Therefore, the voltage value of VIN can be stored in a register in the power supply circuit 200, and the prediction module 360 of the controller according to another embodiment of the present application shown in FIG. 6 is used. Figure 6 Figure 6 In the embodiment, the calculating unit 361 in the controller according to the equation VCSET = V V + (VBATT x V R ) / K generates the preset voltage value, where K is a constant (such as 19 or 12) determined according to the input voltage VIN and can be stored in a register in advance. Compared with the prediction module 360 shown in FIG. 5, Figure 5 Figure 6 The prediction module 360 shown in FIG. 6 omits the divider 504 and the multiplier 506, thereby saving cost.

[0032] Figure 7 FIG. 7 is a flow chart of a method for controlling a voltage converter in a power supply circuit by using a controller according to an embodiment of the present application.

[0033] In step 701, the controller compares the real-time charging current IBATT of the battery with the preset charging current ISET to generate a first comparison result.

[0034] In step 702, the controller compares the real-time battery voltage VBATT with the preset battery voltage VSET to generate a second comparison result.

[0035] In step 703, the controller compares the real-time adapter current IAD with the preset adapter current IADSET to generate a third comparison result.

[0036] In step 704, the controller generates a compensation voltage VCOMP according to the first comparison result, the second comparison result and the third comparison result. ​​

[0037] Step 705, the controller generates a preset voltage value VCSET according to the input voltage VIN and the real-time battery voltage VBATT.

[0038] Step 706, if the real-time adapter current IAD is greater than the preset adapter current IADSET, the power supply circuit enters the parallel power supply mode, and the controller sets the value of the compensation voltage VCOMP to the preset voltage value VCSET.

[0039] Step 707, the controller generates the first switch signal HDR and the second switch signal LDR according to the compensation voltage VCOMP to control the upper side switch and the lower side switch of the voltage converter respectively.

[0040] As described above, the present application discloses a controller for controlling a voltage converter and a method for controlling a voltage converter. When the power required by the system is greater than the power provided by the adapter, the controller sets the value of the compensation voltage VCOMP to a preset voltage value VCSET calculated according to the input voltage VIN and the real-time battery voltage VBATT, so as to quickly meet the requirement of stable operation of the system.

[0041] The foregoing detailed description and accompanying drawings only represent common embodiments of the present application. Obviously, various supplements, modifications and replacements can be made without departing from the spirit and scope of the present application defined by the claims. It should be understood by those skilled in the art that the present application can be changed in form, structure, layout, proportion, material, element, component and other aspects according to specific environment and working requirement without departing from the inventive principle. Therefore, the embodiments disclosed herein are only for illustration but not limitation, and the scope of the present application is defined by the appended claims and their legal equivalents, not limited to the foregoing description.

Claims

1. A controller for controlling a voltage converter, said controller coupled with an adapter, said adapter providing electrical energy to a system and a battery, said voltage converter receiving an input voltage provided by said adapter and generating a real-time charging current for said battery and a real-time battery voltage, characterized in that, The controller comprises: a compensation module, configured to compare the real-time charging current with a preset charging current to generate a first comparison result, compare the real-time battery voltage with a preset battery voltage to generate a second comparison result, compare a real-time adapter current of the adapter with a preset adapter current to generate a third comparison result, and generate a compensation voltage according to the first comparison result, the second comparison result and the third comparison result, wherein the compensation module comprises a first current source configured to charge a capacitor, and a voltage value on the capacitor is the compensation voltage, and the compensation voltage is adjusted by the first comparison result, the second comparison result and the third comparison result; a response adjustment module, configured to set a value of the compensation voltage as a preset voltage value if the real-time adapter current is greater than the preset adapter current; and a driving module, configured to generate a first switch signal and a second switch signal according to the compensation voltage to control an upper switch and a lower switch of the voltage converter respectively.

2. The controller of claim 1, wherein, The compensation module further comprises: a first operational amplifier, configured to compare the real-time charging current with the preset charging current to generate the first comparison result; a second operational amplifier, configured to compare the real-time battery voltage with the preset battery voltage to generate the second comparison result; a third operational amplifier, configured to compare the real-time adapter current with the preset adapter current to generate the third comparison result.

3. The controller of claim 2, wherein, The driving module comprises: a triangular wave generator, configured to generate a triangular wave signal; a first comparator, configured to generate a pulse width modulation signal according to the triangular wave signal and the compensation voltage; and a driver, configured to generate the first switch signal and the second switch signal according to the pulse width modulation signal.

4. The controller of claim 3, wherein, A first input end of the first comparator receives the compensation voltage, a second input end of the first comparator receives the triangular wave signal, and an output end of the first comparator outputs the pulse width modulation signal, wherein the first input end of the first comparator, an output end of the first operational amplifier, an output end of the second operational amplifier, an output end of the third operational amplifier, the first current source and the capacitor are connected to a common node.

5. The controller of claim 3, wherein, The response adjustment module comprises: a prediction module, configured to generate the preset voltage value according to the input voltage and the real-time battery voltage; and a switch unit, coupled between the compensation module and the prediction module, wherein the prediction module turns on the switch unit to set the compensation voltage as the preset voltage value if the real-time adapter current is greater than the preset adapter current.

6. The controller of claim 5, wherein, When the switch unit is turned on, the capacitor is charged by a second current source, and the prediction module turns off the switch unit when the compensation voltage reaches the preset voltage value.

7. The controller of claim 5, wherein, The prediction module comprises: a calculation unit, configured to calculate the preset voltage value; a second comparator, configured to compare the compensation voltage with the preset voltage value; an enabling unit, configured to compare the preset adapter current with the real-time adapter current to generate an enabling signal; and An AND gate for generating a switching signal to control the switching unit according to the output of the second comparator and the enable signal.

8. The controller of claim 7, wherein, The computing unit generates the preset voltage value according to an equation VCSET = V V + (VBATT x V R ) / VIN, wherein VCSET is the preset voltage value, V V is a valley value of the triangular wave signal, VBATT is the real-time battery voltage, V R is a peak-to-peak value of the triangular wave signal, and VIN is the input voltage.

9. The controller of claim 7, wherein, The computing unit generates the preset voltage value according to an equation VCSET = V V + (VBATT x V R ) / K, where VCSET is the preset voltage value, V V is a valley value of the triangular wave signal, VBATT is the real-time battery voltage, V R is a peak-to-peak value of the triangular wave signal, and K is a constant determined according to the input voltage.

10. A method of controlling a voltage converter that receives an input voltage from an adapter and provides a real-time charging current and a real-time battery voltage for a battery, the method comprising: The method comprises: comparing the real-time charging current with a preset charging current to generate a first comparison result; comparing the real-time battery voltage with a preset battery voltage to generate a second comparison result; comparing the real-time adapter current of the adapter with a preset adapter current to generate a third comparison result; generating a compensation voltage according to the first comparison result, the second comparison result and the third comparison result; generating a preset voltage value according to the input voltage and the real-time battery voltage; if the real-time adapter current is greater than the preset adapter current, setting the value of the compensation voltage as the preset voltage value; and generating a first switching signal and a second switching signal according to the compensation voltage to control the upper side switch and the lower side switch of the voltage converter respectively, wherein the step of generating the compensation voltage according to the first comparison result, the second comparison result and the third comparison result comprises: charging a capacitor with a first current source, wherein the voltage value on the capacitor is the compensation voltage; adjusting the voltage value on the capacitor according to the first comparison result, the second comparison result and the third comparison result.

11. The method of claim 10, wherein, The step of generating the first switching signal and the second switching signal according to the compensation voltage comprises: generating a triangular wave signal; generating a pulse width modulation signal according to the triangular wave signal and the compensation voltage; and generating the first switching signal and the second switching signal according to the pulse width modulation signal.

12. The method of claim 11, wherein, The step of generating the preset voltage value according to the input voltage and the real-time battery voltage comprises: According to the equation VCSET = V V + (VBATT x V R ) / VIN, where VCSET is the preset voltage value, V V is the valley value of the triangular wave signal, VBATT is the real-time battery voltage, V R is the peak-to-peak value of the triangular wave signal, and VIN is the input voltage.

13. The method of claim 11, wherein, The step of generating the preset voltage value according to the input voltage and the real-time battery voltage comprises: According to the equation VCSET = V V + (VBATT x V R ) / K, where VCSET is the preset voltage value, V V is the valley value of the triangular wave signal, VBATT is the real-time battery voltage, V R is the peak-to-peak value of the triangular wave signal, and K is a constant determined according to the input voltage.

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