Power conversion circuit with multi-function pin and multi-function setting method thereof

Abstract

The present invention provides a power conversion circuit with a multi-function pin and a multi-function setting method thereof. The multi-function pin is coupled to an external setting circuit. The power conversion circuit includes a first functional circuit, a second functional circuit and a judgment circuit. The first functional circuit is coupled to the multi-function pin. The second functional circuit is coupled to the multi-function pin. The judgment circuit is coupled to the multi-function pin, the first functional circuit and the second functional circuit. The judgment circuit provides a setting current to the multi-function pin so that the external setting circuit generates a voltage according to the setting current. The judgment circuit judges the type of the external setting circuit according to the voltage to correspondingly activate the first functional circuit or the second functional circuit. The present invention also provides a multi-function setting method, which can enable the power conversion circuit to automatically activate the corresponding function according to the type of the external setting circuit.

Description

Technical Field

[0001] The invention relates to a power conversion circuit, and more particularly to a power conversion circuit with multi-functional pins and a multi-functional setting method thereof. Background Art

[0002] In the power conversion circuit architecture, due to the limited number of integrated circuit pins, the function setting pins must be shared with other pins. However, as the demand for power conversion circuits becomes more and more widespread, the existing pins are no longer sufficient. In particular, the existing multi-function pins can only obtain the corresponding voltage to set the parameters of the internal circuit by coupling with external resistors, and the selection of pins is more limited. For example, the soft-start pin of the power conversion circuit needs to be coupled with an external capacitor for soft-start, and cannot be used as a multi-function pin to couple with an external resistor for other function settings. In view of this, several embodiments of the solution will be proposed below. Summary of the invention

[0003] The present invention is directed to a power conversion circuit with multi-functional pins and a multi-functional setting method thereof, which can automatically start corresponding functions according to the type of external setting circuit.

[0004] According to an embodiment of the present invention, a multi-function pin of a power conversion circuit of the present invention is coupled to an external setting circuit. The power conversion circuit includes a first functional circuit, a second functional circuit, and a judgment circuit. The first functional circuit is coupled to the multi-function pin. The second functional circuit is coupled to the multi-function pin. The judgment circuit is coupled to the multi-function pin, the first functional circuit, and the second functional circuit. The judgment circuit provides a setting current to the multi-function pin so that the external setting circuit generates a voltage according to the setting current. The judgment circuit judges the type of the external setting circuit according to the voltage to start the first functional circuit or the second functional circuit accordingly.

[0005] According to an embodiment of the present invention, the external setting circuit is one of a resistor and a capacitor.

[0006] According to an embodiment of the present invention, during the startup period, the current is set to last for a first time, and a voltage is generated at the multi-function pin at the end of the first time.

[0007] According to an embodiment of the present invention, the first functional circuit includes a first current source and a soft start circuit. The first current source is coupled to the multi-function pin, and the soft start circuit is coupled to the multi-function pin. When the judgment circuit determines that the external setting circuit is a capacitor, the judgment circuit starts the first functional circuit so that the first current source provides a first reference current to the multi-function pin, and the external setting circuit generates a soft start voltage according to the first reference current to provide it to the soft start circuit via the multi-function pin, and the soft start circuit performs soft start according to the soft start voltage.

[0008] According to an embodiment of the present invention, the second functional circuit includes a first sub-functional circuit and a second sub-functional circuit. The second functional circuit and the second sub-functional circuit are both coupled to the multi-functional pin. When the judgment circuit determines that the external setting circuit is a resistor, the judgment circuit starts the second functional circuit to enable the first sub-functional circuit to perform a soft start setting, and the second sub-functional circuit provides a second reference current to the multi-functional pin, and the external setting circuit generates a setting voltage according to the second reference current, so that the power conversion circuit performs a multi-functional setting according to the setting voltage.

[0009] According to an embodiment of the present invention, the judgment circuit includes a second current source and a comparator. The second current source is coupled to the multi-function pin and is used to provide a setting current. The inverting input terminal of the comparator is coupled to the multi-function pin, the non-inverting input terminal thereof is coupled to the reference voltage, and the output terminal thereof is coupled to the first functional circuit and the second functional circuit. The second current source outputs the setting current to the multi-function pin during the judgment period, so that the external setting circuit provides a voltage to the multi-function pin according to the setting current, and the comparator compares the voltage with the reference voltage to output a comparison signal.

[0010] According to an embodiment of the present invention, the multi-function setting method of the power conversion circuit of the present invention is applicable to a power conversion circuit having a multi-function pin coupled to an external setting circuit. The multi-function setting method comprises the following steps: providing a setting current to the multi-function pin so that the external setting circuit generates a voltage according to the setting current; and determining the type of the external setting circuit according to the voltage to start the first function circuit or the second function circuit accordingly.

[0011] According to an embodiment of the present invention, in the step of providing a set current to the multi-function pin, the set current lasts for a first time, and the voltage is compared with a reference voltage at the end of the first time.

[0012] According to an embodiment of the present invention, the step of determining the type of the external setting circuit based on the voltage to correspondingly start the first functional circuit or the second functional circuit includes: when it is determined that the external setting circuit is a capacitor, starting the first functional circuit so that the first functional circuit provides a first reference current to the multi-function pin; and generating a soft start voltage according to the first reference current through the external setting circuit to perform soft start according to the soft start voltage.

[0013] According to an embodiment of the present invention, the step of determining the type of the external setting circuit based on the voltage to correspondingly start the first functional circuit or the second functional circuit includes: when it is determined that the external setting circuit is a resistor, starting the second functional circuit so that the first sub-functional circuit of the second functional circuit performs a soft start setting, and the second sub-functional circuit of the second functional circuit provides a second reference current to the multi-function pin; and generating a setting voltage according to the second reference current through the external setting circuit, and the power conversion circuit performs a multi-function setting according to the setting voltage.

[0014] Based on the above, the power conversion circuit with multi-function pins and the multi-function setting method thereof of the present invention can automatically determine the type of the external setting circuit to perform soft-start or other function settings accordingly.

[0015] In order to make the above features and advantages of the present invention more clearly understood, embodiments are given below with reference to the accompanying drawings for detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The accompanying drawings are included to provide a further understanding of the present invention and are incorporated in and constitute a part of this specification. The drawings illustrate embodiments of the present invention and together with the description serve to explain the principles of the present invention.

[0017] Figure 1 is a block diagram of a power conversion circuit according to an embodiment of the present invention;

[0018] Figure 2 is a circuit diagram of a power conversion circuit according to an embodiment of the present invention;

[0019] Figure 3 is a circuit diagram of a power conversion circuit according to another embodiment of the present invention;

[0020] Figure 4 A signal waveform diagram of a power conversion circuit according to an embodiment of the present invention;

[0021] Figure 5 FIG. 4 is a flow chart of a multi-function setting method according to an embodiment of the present invention.

[0022] Description of Figure Numbers

[0023] 100, 300, 300': Power conversion circuit

[0024] 110, 310, 310': Judgment circuit

[0025] 120, 320, 320': First functional circuit

[0026] 130, 330, 330': Second functional circuit

[0027] 140, 340, 340': Multi-function pins

[0028] 200: External setting circuit

[0029] 311, 322, 311', 322': Current source

[0030] 312, 312': switch

[0031] 313, 313': Comparator

[0032] 314, 314': Inverter

[0033] 321, 331, 321', 331': Transistor switches

[0034] 323, 323': Soft start circuit

[0035] 332, 332': first sub-functional circuit

[0036] 333, 333': Second sub-functional circuit

[0037] 400: Capacitance

[0038] 500: Resistance

[0039] Iset: set current

[0040] Iref1, Iref2: reference current

[0041] Vset_R, Vset_C: voltage

[0042] Vc_R, Vc_C: comparison signal

[0043] t1, t2, t3, t4, t5, t6: time

[0044] S610~S620: Steps DETAILED DESCRIPTION

[0045] Reference will now be made in detail to exemplary embodiments of the present invention, examples of which are illustrated in the accompanying drawings. Whenever possible, the same reference numerals are used in the drawings and the description to refer to the same or like parts.

[0046] Figure 1 FIG. 1 is a block diagram of a power conversion circuit according to an embodiment of the present invention. Figure 1The power conversion circuit 100 includes a judgment circuit 110, a first function circuit 120, a second function circuit 130 and a multi-function pin 140. The judgment circuit 110 is coupled to the first function circuit 120, the second function circuit 130 and the multi-function pin 140, and the first function circuit 120 and the second function circuit 130 are coupled to the multi-function pin 140. In this embodiment, the power conversion circuit 100 is coupled to the external setting circuit 200 through the multi-function pin 140. When the power conversion circuit 100 is started, the judgment circuit 110 provides a setting current to the multi-function pin 140, so that the external setting circuit 200 generates a corresponding voltage according to the setting current. Then, the judgment circuit 110 can judge the type of the external setting circuit 200 according to the corresponding voltage returned by the external setting circuit 200 through the multi-function pin 140, so as to start the first function circuit 120 or the second function circuit 130 accordingly. Therefore, the power conversion circuit 100 of this embodiment can automatically determine the type of the external setting circuit 200 externally coupled to the multi-function pin 140 to activate the corresponding function. From another perspective, the user can selectively couple a specific external setting circuit 200 to the multi-function pin 140 of the power conversion circuit 100 of this embodiment according to the specific function of the power conversion circuit 100 that is desired to be activated, so that the power conversion circuit 100 of this embodiment automatically determines the type of the external setting circuit 200 and activates the specific function.

[0047] In this embodiment, the first functional circuit 120 may include a soft-start circuit, and the second functional circuit 130 may include a first sub-functional circuit and a second sub-functional circuit. In addition, the external setting circuit 200 is selectively one of a capacitor and a resistor. Taking the external setting circuit 200 as a capacitor as an example, when the judgment circuit 110 determines that the external setting circuit 200 is a capacitor, the judgment circuit 110 starts the first functional circuit 120, and the soft-start circuit of the first functional circuit 120 can be soft-started according to the voltage generated by the external setting circuit 200. In other words, when the external setting circuit 200 is a capacitor, the power conversion circuit 100 can be soft-started through the external setting circuit 200. Taking the external setting circuit 200 as a resistor as an example, when the judgment circuit 110 determines that the external setting circuit 200 is a resistor, the judgment circuit 110 starts the second functional circuit 130, and the first sub-functional circuit of the second functional circuit 130 can be a soft-start setting circuit of the power conversion circuit 100, so as to perform soft-start through the built-in soft-start parameters. Furthermore, the second sub-function circuit of the second function circuit 130 provides a second reference current to the multi-function pin 140, so that the external setting circuit 200 generates a setting voltage according to the second reference current. Then, the multi-function pin 140 can feed back the setting voltage to the second sub-function circuit of the second function circuit 130, so that the second sub-function circuit further performs the multi-function setting of the power conversion circuit 100. In other words, when the external setting circuit 200 is a resistor, the power conversion circuit 100 can perform soft start through the internal soft start circuit, and the multi-function setting of the power conversion circuit 100 can be started through the external setting circuit 200.

[0048] Figure 2 FIG. 1 is a circuit diagram of a power conversion circuit according to an embodiment of the present invention. Figure 2 , the power conversion circuit 300 includes a judgment circuit 310, a first function circuit 320, a second function circuit 330 and a multi-function pin 340. The judgment circuit 310 is coupled to the first function circuit 320, the second function circuit 330 and the multi-function pin 340, and the first function circuit 320 and the second function circuit 330 are also coupled to the multi-function pin 340. The power conversion circuit 300 is coupled to the capacitor 400 through the multi-function pin 340. In this embodiment, the judgment circuit 310 includes a current source 311, a switch 312, a comparator 313 and an inverter 314. One end of the current source 311 is coupled to the multi-function pin 340, the switch 312 and the first input end of the comparator 313. The non-inverting input end of the comparator 313 is coupled to the current source 311 and the switch 312, and the inverting input end of the comparator 313 is coupled to the reference voltage Vref. The output end of the comparator 313 is coupled to the input end of the inverter 314. An output terminal of the inverter 314 is coupled to the first functional circuit 320 and the second functional circuit 330 .

[0049] In the present embodiment, the first functional circuit 320 includes a transistor switch 321, a current source 322, and a soft start circuit 323. The transistor switch 321 is a P-type transistor. The first end of the transistor switch 321 is coupled to the multi-function pin 340, and the second end of the transistor switch 321 is coupled to the current source 322 and the soft start circuit 323. The control end of the transistor switch 321 is coupled to the output end of the comparator 313. In the present embodiment, the second functional circuit 330 includes a transistor switch 331, a first sub-function circuit 332, and a second sub-function circuit 333. The transistor switch 331 is a P-type transistor. The first end of the transistor switch 331 is coupled to the multi-function pin 340, and the second end of the transistor switch 331 is coupled to the first sub-function circuit 332 and the second sub-function circuit 333. The control end of the transistor switch 331 is coupled to the output end of the inverter 314.

[0050] In this embodiment, the capacitor 400 is used as an external setting circuit, and the power conversion circuit 300 is coupled to the capacitor 400 via the multi-function pin 340. Figure 2 as well as Figure 4 , Figure 4 is a signal waveform diagram of a power conversion circuit according to an embodiment of the present invention, and Figure 4 Including signal waveform changes when the external setting circuit is a capacitor 400. In this embodiment, before time t1, the transistor switch 312 of the judgment circuit 310 is turned on to discharge the capacitor 400. Between time t1 and time t2, the transistor switch 312 is turned off and not turned on. The current source 311 of the judgment circuit 310 can provide a set current Iset (or pulse current) to the multi-function pin 340. Then, when the capacitor 400 receives the set current Iset through the multi-function pin 340, the capacitor 400 is charged to generate a corresponding voltage Vset_C, and the positive input terminal of the comparator 313 can receive the voltage Vset_C. In this regard, since the capacitor 400 receives the set current Iset with a fixed current value, a gradually increasing voltage change will be generated such as Figure 4 However, since the capacitor 400 can be selected by the user to have a specific capacitance value, so that the voltage Vset_C provided by the capacitor 400 will not be higher than the reference voltage Vref, the output end of the comparator 313 will output a comparison signal Vc_C of a low voltage level to the control end of the transistor switch 321 of the first functional circuit 320 to turn on the transistor switch 321. Moreover, after the comparison signal is inverted by the inverter 314, the output end of the inverter 314 will output another comparison signal of a high voltage level to the control end of the transistor switch 331 of the second functional circuit 330 to turn off the transistor switch 331.

[0051] At time t3, since the transistor switch 321 of the first functional circuit 320 is turned on, the current source 322 of the first functional circuit 320 can provide the first reference current Iref1 to the multi-function pin 340 via the transistor switch 321, so that the multi-function pin 340 receives the first reference current Iref1. Then, when the capacitor 400 receives the first reference current Iref1 through the multi-function pin 340, a corresponding voltage Vset_C is generated at the multi-function pin 340. Therefore, Figure 4 As shown, between time t3 and time t6, the voltage Vset_C gradually rises to perform soft start of the power conversion circuit 300. Accordingly, in this embodiment, the power conversion circuit 300 can automatically determine that the external setting circuit is the capacitor 400 and perform the corresponding soft start function.

[0052] Figure 3 FIG. 1 is a circuit diagram of a power conversion circuit according to another embodiment of the present invention. Figure 3 as well as Figure 4 , compared with the above Figure 2 In another embodiment, the resistor 500 is used as an external setting circuit, and the power conversion circuit 300' is coupled to the resistor 500 through the multi-function pin 340'. Figure 3 as well as Figure 4 , Figure 4 Including signal waveform changes when the external setting circuit is the resistor 500. In the present embodiment, before time t1, the transistor switch 312' of the judgment circuit 310' is turned on to discharge the multi-function pin 340'. Between time t1 and time t2, the transistor switch 312' is turned off and not turned on. The current source 311' of the judgment circuit 310' can provide a set current Iset (or pulse current) to the multi-function pin 340'. Then, when the resistor 500 receives the set current Iset through the multi-function pin 340', a corresponding voltage Vset_R is generated at the multi-function pin 340', and the inverting input terminal of the comparator 313' receives the voltage Vset_R. In response to this, the resistor 500 generates a corresponding fixed voltage such as in response to the set current Iset having a fixed current value. Figure 4 However, since the resistor 500 can be selected by the user to have a specific resistance value, so that the voltage Vset_R provided by the resistor 500 will be higher than the reference voltage Vref, the output end of the comparator 313' will output a comparison signal Vc_R of a high voltage level to the control end of the transistor switch 321' of the first functional circuit 320' to turn off the transistor switch 321'. Moreover, after the comparison signal is inverted by the inverter 314', the output end of the inverter 314' will output another comparison signal of a low voltage level to the control end of the transistor switch 331' of the second functional circuit 330' to turn on the transistor switch 331'.

[0053] At time t3, since the transistor switch 331' of the second functional circuit 330' is turned on, the first sub-functional circuit 332' and the second sub-functional circuit 333' of the second functional circuit 330' will be enabled. Between time t3 and time t4, the first sub-functional circuit 332' performs a soft start of the power conversion circuit 300' based on the internal setting. And, between time t5 and time t6, the second sub-functional circuit 333' provides a second reference current Iref2 to the multi-function pin 340', so that the resistor 500 generates a corresponding voltage Vset_R according to the second reference current Iref2. Therefore, if Figure 4 As shown, between time t5 and time t6, voltage Vset_R is a fixed voltage, and power conversion circuit 300' can perform multi-function settings according to voltage Vset_R. Accordingly, in this embodiment, power conversion circuit 300' can automatically determine that the external setting circuit is resistor 500, and perform corresponding soft start and multi-function settings.

[0054] Figure 5 FIG. 1 is a flowchart of a multi-function setting method according to an embodiment of the present invention. Figure 1 as well as Figure 5 The multi-function setting method of this embodiment can be applied to at least Figure 1 The power conversion circuit 100 of the embodiment is configured to enable the power conversion circuit 100 to perform the following steps S610 and S620. In step S610, the determination circuit 110 of the power conversion circuit 100 can provide a setting current to the multi-function pin 140, so that the external setting circuit 200 generates a voltage according to the setting current. In step S620, the power conversion circuit 100 determines the type of the external setting circuit 200 according to the voltage signal, so as to start the first function circuit 120 or the second function circuit 130 accordingly. Therefore, the multi-function setting method of the embodiment can enable the power conversion circuit 100 to automatically perform the corresponding function according to the type of the external setting circuit 200.

[0055] In addition, other implementations, technical details and component features of the multi-function setting method and the power conversion circuit 100 of this embodiment can be obtained by Figures 1 to 4 Sufficient teachings, suggestions and implementation instructions are obtained from the description of the embodiments, so they are not repeated here.

[0056] In summary, the power conversion circuit and the multi-function setting method of the present invention can be applied to the case where the external setting circuit is a capacitor or a resistor. The power conversion circuit and the multi-function setting method of the present invention can provide a setting current to the external setting circuit to effectively determine whether the external setting circuit is a capacitor or a resistor based on the voltage returned by the external setting circuit, and then perform soft start, soft start setting or other multi-function settings. In other words, the power conversion circuit and the multi-function setting method of the present invention can automatically determine and execute the function setting of the corresponding power conversion circuit based on the type of external setting circuit designed by the user.

[0057] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A power conversion circuit having a multi-function pin, wherein the multi-function pin is coupled to an external setting circuit, characterized in that: The power conversion circuit comprises: A first functional circuit coupled to the multi-function pin; A second functional circuit coupled to the multi-function pin; and A judgment circuit is coupled to the multi-function pin, the first function circuit and the second function circuit, and provides a setting current to the multi-function pin so that the external setting circuit generates a voltage according to the setting current. When the judgment circuit determines that the external setting circuit is a capacitor according to the voltage, the judgment circuit starts the first functional circuit. When the judgment circuit determines that the external setting circuit is a resistor according to the voltage, the judgment circuit starts the second functional circuit.

2. The power conversion circuit according to claim 1, characterized in that: During the startup period, the set current lasts for a first time, and the voltage is generated at the multi-function pin at the end of the first time.

3. The power conversion circuit according to claim 1, characterized in that: The first functional circuit comprises: A first current source coupled to the multi-function pin; and A soft start circuit is coupled to the multi-function pin, When the judgment circuit determines that the external setting circuit is a capacitor, the judgment circuit activates the first functional circuit so that the first current source provides a first reference current to the multi-function pin. The external setting circuit generates a soft start voltage according to the first reference current to provide it to the soft start circuit via the multi-function pin. The soft start circuit performs a soft start according to the soft start voltage.

4. The power conversion circuit according to claim 1, characterized in that: The second functional circuit comprises: A first sub-function circuit coupled to the multi-function pin; and The second sub-function circuit is coupled to the multi-function pin, When the judgment circuit determines that the external setting circuit is a resistor, the judgment circuit starts the second functional circuit to enable the first sub-functional circuit to perform a soft start setting, and the second sub-functional circuit provides a second reference current to the multi-function pin, and the external setting circuit generates a setting voltage based on the second reference current, so that the power conversion circuit performs a multi-function setting based on the setting voltage.

5. The power conversion circuit according to claim 1, characterized in that: The judgment circuit comprises: a second current source coupled to the multi-function pin and configured to provide the set current; and a comparator, whose inverting input terminal is coupled to the multi-function pin, whose non-inverting input terminal is coupled to the reference voltage, and whose output terminal is coupled to the first functional circuit and the second functional circuit, The second current source outputs the setting current to the multi-function pin during the determination period, so that the external setting circuit provides the voltage to the multi-function pin according to the setting current, and the comparator compares the voltage with the reference voltage to output a comparison signal.

6. A multi-function setting method for a power conversion circuit, wherein the power conversion circuit has a multi-function pin coupled to an external setting circuit, characterized in that: The multifunctional setting method comprises: Providing a setting current to the multi-function pin so that the external setting circuit generates a voltage according to the setting current; and Determining the type of the external setting circuit according to the voltage to start the first function circuit or the second function circuit accordingly; When it is determined that the external setting circuit is a capacitor, starting the first functional circuit; and When it is determined that the external setting circuit is a resistor, the second functional circuit is started.

7. The multifunctional setting method according to claim 6, characterized in that: In the step of providing the setting current to the multi-function pin, the setting current continues for a first time, and the voltage is compared with a reference voltage at the end of the first time.

8. The multifunctional setting method according to claim 6, characterized in that: The step of determining the type of the external setting circuit according to the voltage to correspondingly activate the first functional circuit or the second functional circuit comprises: When it is determined that the external setting circuit is a capacitor and the first functional circuit is activated, the first functional circuit provides a first reference current to the multi-function pin; and A soft start voltage is generated by the external setting circuit according to the first reference current, so as to perform soft start according to the soft start voltage.

9. The multifunctional setting method according to claim 6, characterized in that: The step of determining the type of the external setting circuit according to the voltage to correspondingly activate the first functional circuit or the second functional circuit comprises: When it is determined that the external setting circuit is a resistor and the second functional circuit is started, the first sub-functional circuit of the second functional circuit is set to soft start, and the second sub-functional circuit of the second functional circuit provides a second reference current to the multi-functional pin; and The external setting circuit generates a setting voltage according to the second reference current, and the power conversion circuit performs multi-function setting according to the setting voltage.

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