Power converter with switch assembly having different safe operating areas

Abstract

A power converter with a switch assembly having different safe operating areas is disclosed. A first end of a first upper bridge switch is coupled to a shared voltage. A first end of a first lower bridge switch is connected to a second end of the first upper bridge switch. A second end of the first lower bridge switch is connected to ground. A first end of a second lower bridge switch is connected to a node between the second end of the first upper bridge switch and the first end of the first lower bridge switch. A second end of the second lower bridge switch is connected to ground. The safe operating area of the second lower bridge switch is greater than the safe operating area of the first lower bridge switch. The second lower bridge switch is turned off after the first lower bridge switch is turned off. The second lower bridge switch is turned on before the first lower bridge switch is turned on.

Description

Technical Field

[0001] This invention relates to power converters, and more particularly to a power converter with a switching assembly having different safe operating areas. Background Technology

[0002] Power converters are widely used in various electronic products to convert electrical energy for use in these devices. When a switching power converter is used as a charger, it requires multiple transistors as components of the drive circuit, and the power conversion is achieved through the switching action of the transistors.

[0003] When the lower-bridge transistor of a traditional power converter switches from the on state to the off state, it undergoes the following process: Figure 7 and Figure 8 The Miller flat region is shown in box A. When the lower-bridge transistor of a conventional power converter switches from the off state to the on state, it undergoes the following process: Figure 8 The box B shown represents the Miller flat region. During the Miller flat region, the lower-bridge transistor's voltage rating is at its weakest, making it susceptible to damage from excessive current.

[0004] Similarly, when the bridge transistor switches from the on state to the off state or from the off state to the on state, it will experience a period of time as follows: Figure 9 The Miller flat region enclosed by boxes A and B is where the upper-bridge transistor has the weakest voltage withstand capability. However, due to the energy dissipation of inductor L, the voltage at the second node LX2 will rise to 0.7V, resulting in a large voltage difference between the drain and source of the upper-bridge transistor, which can lead to its failure.

[0005] To prevent damage from excessive current, the transistors in the drive circuit of the power converter need to have a large layout area and a large on-resistance (Ron). This requires the transistors to have high voltage withstand capability and the ability to withstand large currents. However, this results in greater power loss during the operation of the power converter. Summary of the Invention

[0006] The technical problem to be solved by this invention is to provide a power converter with switching components having different safe operating areas, addressing the shortcomings of existing technologies. The converter includes a first upper bridge switch, a first lower bridge switch, a second lower bridge switch, an upper bridge drive circuit, and a lower bridge drive circuit. A first terminal of the first upper bridge switch is coupled to a shared voltage. A first terminal of the first lower bridge switch is connected to a second terminal of the first upper bridge switch. The second terminal of the first lower bridge switch is grounded. A first terminal of the second lower bridge switch is connected to a first node between the second terminal of the first upper bridge switch and the first terminal of the first lower bridge switch. The second terminal of the second lower bridge switch is grounded. The first node is grounded through a series circuit of an inductor and a capacitor. The upper bridge drive circuit is connected to the control terminal of the first upper bridge switch. The upper bridge drive circuit is configured to drive the first upper bridge switch to open or close. The lower bridge drive circuit is connected to the control terminal of the first lower bridge switch. The lower bridge drive circuit is configured to drive the first lower bridge switch to open or close. The safe operating area of ​​the second lower bridge switch is larger than that of the first lower bridge switch. The first upper bridge switch and the first lower bridge switch switch complement each other. After the lower bridge drive circuit closes the first lower bridge switch, the lower bridge drive circuit closes the second lower bridge switch. Before the lower bridge drive circuit turns on the first lower bridge switch, the lower bridge drive circuit turns on the second lower bridge switch.

[0007] In one embodiment, the power converter with switching assemblies having different safe operating areas further includes a resistor connected in parallel with a capacitor. The output node between the capacitor and the inductor is the output terminal of the power converter.

[0008] In one embodiment, the lower bridge drive circuit includes a first NOR gate, a second NOR gate, a first NOT gate, a second NOT gate, a first AND gate, and a second AND gate. The first input of the first NOR gate is connected to the control terminal of the first upper bridge switch. The second input of the first NOR gate is connected to the output terminal of the pulse signal generator. The two inputs of the first AND gate are respectively connected to the output terminal of the first NOR gate and the control terminal of the second lower bridge switch. The output terminal of the first AND gate is connected to the control terminal of the first lower bridge switch. The two inputs of the second NOR gate are respectively connected to the output terminal of the first NOR gate and the control terminal of the first lower bridge switch. The output terminal of the second NOR gate is connected to the input terminal of the second NOT gate. The output terminal of the second NOT gate is connected to the control terminal of the second lower bridge switch. The input of the first NOT gate is connected to the control terminal of the second lower bridge switch. The two inputs of the second AND gate are respectively connected to the output terminals of the second NOR gate and the first NOT gate. The input terminal of the upper bridge drive circuit is connected to the output terminal of the second AND gate and the output terminal of the pulse signal generator.

[0009] In one embodiment, the power converter with the switching assemblies having different safe operating areas further includes a first buffer. The first buffer is connected between the output of the first AND gate and the control terminal of the first downbridge switch.

[0010] In one embodiment, the power converter with the switching assemblies having different safe operating areas further includes a second buffer. The second buffer is connected between the output of the second NOT gate and the control terminal of the second lower bridge switch.

[0011] In one embodiment, the power converter of the switching assemblies with different safe operating areas further includes a second upper bridge switch. A first terminal of the second upper bridge switch is coupled to a shared voltage. A control terminal of the second upper bridge switch is connected to the output of the upper bridge drive circuit. A second terminal of the second upper bridge switch is connected to a first terminal of a second lower bridge switch. A second node between the second terminal of the second upper bridge switch and the first terminal of the second lower bridge switch is grounded through a series circuit. The safe operating area of ​​the second upper bridge switch is larger than that of the first upper bridge switch.

[0012] In one embodiment, the upper bridge drive circuit includes a third AND gate, a fourth AND gate, a third NOR gate, a third NOT gate, a fourth NOT gate, and a first NAND gate. The first input of the third AND gate is connected to the output of a pulse signal generator. The second input of the third AND gate is connected to the output of a second AND gate. The first and second inputs of the fourth AND gate are respectively connected to the output of the third AND gate and the control terminal of the second upper bridge switch. The output of the second AND gate is connected to the control terminal of the first upper bridge switch. The two inputs of the third NOR gate are respectively connected to the output of the third AND gate and the control terminal of the first upper bridge switch. The output of the third NOR gate is connected to the input of the third NOT gate. The output of the third NOT gate is connected to the control terminal of the second upper bridge switch. The input of the fourth NOT gate is connected to the control terminal of the second lower bridge switch. The two inputs of the first NAND gate are respectively connected to the output of the third NOR gate and the output of the fourth NOT gate. The output of the first NAND gate is connected to the first input of the first NOR gate.

[0013] In one embodiment, the power converter with switching components having different safe operating areas further includes a delay circuit. The delay circuit is connected between the output of the first NAND gate and the first input of the first NOR gate.

[0014] In one embodiment, the power converter of the switching assemblies with different safe operating areas further includes a potential conversion circuit. The potential conversion circuit is connected between the output of the delay circuit and the first input of the fourth AND gate.

[0015] In one embodiment, the power converter of the switching assemblies with different safe operating areas further includes a second upper-bridge switch. A first terminal of the second upper-bridge switch is coupled to a shared voltage, and a control terminal of the second upper-bridge switch is connected to the output of the upper-bridge drive circuit. A second terminal of the second upper-bridge switch is connected to a first terminal of a second lower-bridge switch. A second node between the second terminal of the second upper-bridge switch and the first terminal of the second lower-bridge switch is grounded through a series circuit. The safe operating area of ​​the second upper-bridge switch is larger than the safe operating area of ​​the first upper-bridge switch.

[0016] In one embodiment, after the upper bridge drive circuit closes the first upper bridge switch, the upper bridge drive circuit closes the second upper bridge switch. Before the upper bridge drive circuit opens the first upper bridge switch, the upper bridge drive circuit opens the second upper bridge switch.

[0017] In one embodiment, the upper bridge drive circuit includes a first AND gate, a second AND gate, a first NOR gate, a first NOT gate, a second NOT gate, and a first NAND gate. The first input of the first AND gate is connected to the output of a pulse signal generator. The second input of the first AND gate is connected to the output of the lower bridge drive circuit. The first input of the second AND gate is connected to the output of the first AND gate. The second input of the second AND gate is connected to the control terminal of the second upper bridge switch. The output of the second AND gate is connected to the input of the upper bridge drive circuit. The output of the second AND gate is connected to the control terminal of the first upper bridge switch. The first and second inputs of the first NOR gate are respectively connected to the output of the first AND gate and the control terminal of the first upper bridge switch. The output of the first NOR gate is connected to the input of the first NOT gate. The output of the first NOT gate is connected to the control terminal of the second upper bridge switch. The input of the second NOT gate is connected to the control terminal of the second lower bridge switch. The two inputs of the first NAND gate are respectively connected to the input of the lower bridge drive circuit.

[0018] In one embodiment, the power converter of the switching assemblies with different safe operating areas further includes a potential conversion circuit. This potential conversion circuit is connected between the output of the first AND gate and the first input of the second AND gate.

[0019] In one embodiment, the power converter of the switching assemblies with different safe operating areas further includes a first buffer. This first buffer is connected between the output of the second AND gate and the control terminal of the first upper bridge switch.

[0020] As described above, the present invention provides a power converter with switching components having different safe operating areas. It uses two upper bridge switching components or two lower bridge switching components with different safe operating area sizes to achieve the same on-resistance value with a smaller layout area. This reduces the overall size of the power converter chip while still preventing the switching components with poor voltage withstand capability from being damaged due to their inability to withstand excessive current or voltage.

[0021] To further understand the features and technical content of this invention, please refer to the following detailed description and drawings of this invention. However, the drawings provided are for reference and illustration only and are not intended to limit this invention. Attached Figure Description

[0022] Figure 1 This is a circuit layout diagram of a power converter with switching components having different safe operating areas, according to a first embodiment of the present invention.

[0023] Figure 2 This is a circuit layout diagram of a power converter with switching components having different safe operating areas, according to a second embodiment of the present invention.

[0024] Figure 3 This is a circuit layout diagram of a power converter with switching components having different safe operating areas, according to a third embodiment of the present invention.

[0025] Figure 4 This is a circuit layout diagram of a power converter with switching components having different safe operating areas, according to a fourth embodiment of the present invention.

[0026] Figure 5 This is a circuit layout diagram of a power converter with switching components having different safe operating areas, according to a fifth embodiment of the present invention.

[0027] Figure 6 The above are signal waveform diagrams of power converters with switching components having different safe operating areas according to various embodiments of the present invention.

[0028] Figure 7 This is a waveform diagram of a traditional power converter.

[0029] Figure 8 This is a waveform diagram of a traditional power converter.

[0030] Figure 9 This is a waveform diagram of a traditional power converter. Detailed Implementation

[0031] The following specific embodiments illustrate the implementation of the present invention. Those skilled in the art can understand the advantages and effects of the present invention from the content disclosed in this specification. The present invention can be implemented or applied through other different specific embodiments, and various details in this specification can also be modified and changed based on different viewpoints and applications without departing from the concept of the present invention. Furthermore, the accompanying drawings of the present invention are for simple illustrative purposes only and are not depictions of actual dimensions, as stated in advance. The following embodiments will further describe the relevant technical content of the present invention in detail, but the disclosed content is not intended to limit the scope of protection of the present invention. In addition, the term "or" as used herein may, depending on the actual situation, include any combination of any one or more of the associated listed items.

[0032] [First Embodiment]

[0033] Please see Figure 1 and Figure 6 ,in Figure 1 This is a circuit layout diagram of a power converter with switching components having different safe operating areas according to a first embodiment of the present invention. Figure 6The above are signal waveform diagrams of power converters with switching components having different safe operating areas according to various embodiments of the present invention.

[0034] The power converter described herein may be, for example, a buck converter, but this is only for illustrative purposes and is not intended to limit the invention.

[0035] It is worth noting that, such as Figure 1 As shown, the power converter in this embodiment of the invention includes a first upper bridge switch M3 and a first lower bridge switch M1, as well as a second lower bridge switch M2. The safe operating area (SOA) of the second lower bridge switch M2 is larger than that of the first lower bridge switch M1, and is used to protect the first lower bridge switch M1.

[0036] The first terminal of the first upper bridge switch M3 is coupled to the shared voltage VIN. The first terminal of the first lower bridge switch M1 is connected to the second terminal of the first upper bridge switch M3. The second terminal of the first lower bridge switch M1 is grounded.

[0037] The first node LX1 between the second terminal of the first upper bridge switch M3 and the first terminal of the first lower bridge switch M1 is grounded through a series circuit of inductor L and capacitor C. Specifically, the first node LX1 is connected to the first terminal of inductor L. The second terminal of inductor L is connected to the first terminal of capacitor C. The second terminal of capacitor C is grounded. The output node between inductor L and capacitor C is the output terminal of the power converter, with an output voltage Vout. Capacitor C can be connected in parallel with a resistor R.

[0038] The first terminal of the second lower bridge switch M2 is connected to the first node LX1 between the second terminal of the first upper bridge switch M3 and the first terminal of the first lower bridge switch M1, as well as the first terminal of the inductor L1. The second terminal of the second lower bridge switch M2 is grounded.

[0039] Additionally, the power converter in this embodiment may further include an upper bridge drive circuit 100 and a lower bridge drive circuit 200. The upper bridge drive circuit 100 may be connected to the control terminal of the first upper bridge switch M3. The lower bridge drive circuit 200 may be connected to the control terminal of the first lower bridge switch M1.

[0040] If necessary, the power converter in this embodiment of the invention may include a first buffer 301 for the first upper bridge switch M3, connected between the upper bridge drive circuit 100 and the control terminal of the first upper bridge switch M3, and may serve as a delay or relay component for the first upper bridge drive signal UG1 output by the upper bridge drive circuit 100 to the first upper bridge switch M3.

[0041] The input terminals of the upper bridge drive circuit 100 and the lower bridge drive circuit 200 can be connected to an external pulse signal generator (not shown) to receive a pulse width modulation (PWM) signal from the pulse signal generator. The upper bridge drive circuit 100 can output a first upper bridge drive signal UG1 with a high or low potential according to the PWM signal to drive the first upper bridge switch M3 to turn on or off.

[0042] The lower bridge drive circuit 200 can output a first lower bridge drive signal LG1 and a second lower bridge drive signal LG2 with high or low potentials according to the pulse width modulation signal PWM, so as to drive the first lower bridge switch M1 and the second lower bridge switch M2 to turn on or off respectively.

[0043] For example, when the pulse width modulation signal PWM is high, the lower bridge drive circuit 200 outputs a low-level first lower bridge drive signal LG1 to the first lower bridge switch M1 to turn off the first lower bridge switch M1. Then, the lower bridge drive circuit 200 outputs a low-level second lower bridge drive signal LG2 to the second lower bridge switch M2 to turn off the second lower bridge switch M2.

[0044] Conversely, when the pulse width modulation signal PWM is low, the lower bridge drive circuit 200 outputs a high-level second lower bridge drive signal LG2 to the second lower bridge switch M2 to turn on the second lower bridge switch M2. Then, the lower bridge drive circuit 200 outputs a high-level first lower bridge drive signal LG1 to the first lower bridge switch M1 to turn on the first lower bridge switch M1.

[0045] In other words, after the lower bridge drive circuit 200 closes the first lower bridge switch M1, which has a larger safe operating area, the lower bridge drive circuit 200 begins to close the second lower bridge switch M2, which has a smaller safe operating area. Before the lower bridge drive circuit 200 opens the first lower bridge switch M1, which has a smaller safe operating area, the lower bridge drive circuit 200 first opens the second lower bridge switch M2, which has a larger safe operating area.

[0046] Additionally, the power converter in this embodiment of the invention may include a first buffer 401 for a first downbridge switch M1 and a second buffer 402 for a second downbridge switch M2. The first buffer 401 is connected between the output terminal of the downbridge drive circuit 200 and the control terminal of the first downbridge switch M1. The second buffer 402 is connected between the output terminal of the downbridge drive circuit 200 and the control terminal of the second downbridge switch M2. The first buffer 401 and the second buffer 402 may respectively serve as delay or relay components for the first downbridge drive signal LG1 output by the downbridge drive circuit 200 to the first downbridge switch M1 and the second downbridge drive signal LG2 output by the downbridge drive circuit 200 to the second downbridge switch M2.

[0047] The first upper bridge switch M3 and the first lower bridge switch M1 switch complement each other. Therefore, when the upper bridge drive circuit 100 wants to drive the first upper bridge switch M3 to switch from the closed state to the open state, such as... Figure 6 The first lower bridge drive signal LG1 shown drops from a high potential to a low potential, indicating that the lower bridge drive circuit 200 drives the first lower bridge switch M1 to switch from the on state to the off state.

[0048] After the first lower bridge switch M1, which has a smaller safe operating area, is closed for a period of time, the lower bridge drive circuit 200 begins to close the second lower bridge switch M2, which has a larger safe operating area. The second lower bridge switch M2, with its larger safe operating area, bears the energy caused by the inductor L, resulting in... Figure 6 The voltage rise of the voltage signal LXS of the first node LX1 is shown.

[0049] When the upper bridge drive circuit 100 drives the first upper bridge switch M3 to switch from the on state to the off state, such as Figure 6 The lower bridge drive signal LG1 rises from a low level to a high level, indicating that the lower bridge drive circuit 200 first drives the second lower bridge switch M2 to turn on. Thus, the second lower bridge switch M2, with its larger safe operating area, can... Figure 6 The voltage signal LXS of the first node LX shown is pulled down to a low voltage from the high voltage and the voltage signal UXS of the second terminal of the first upper bridge switch M3. When the voltage of the first node LX reaches a low voltage, the lower bridge drive circuit 200 drives the first lower bridge switch M1 to open, to prevent the first lower bridge switch M1, which has a small safe operating area and low withstand voltage, from being damaged due to the excessive voltage of the first node LX.

[0050] If necessary, the power converter in this embodiment of the invention may further include a potential conversion circuit 602 and a delay circuit 500. The input terminal of the potential conversion circuit 602 may be connected to the control terminal of the first upper bridge switch M3. The output terminal of the potential conversion circuit 602 may be connected to the input terminal of the delay circuit 500. The output terminal of the delay circuit 500 may be connected to the input terminal of the lower bridge drive circuit 200.

[0051] When the first upper bridge switch M3 changes from the open state to the closed state, and the first lower bridge switch M1 changes from the closed state to the open state, the potential conversion circuit 602 can convert the first upper bridge drive signal UG1 of the first upper bridge switch M3 from a high potential to a low potential to prevent excessive voltage from being injected into the first lower bridge switch M1. The delay circuit 500 can delay the phase of the converted first upper bridge drive signal UG1.

[0052] The lower bridge drive circuit 200 can output a lower bridge turn-on signal LGD to the upper bridge drive circuit 100 based on the first upper bridge drive signal UG1 received from the delay circuit 500. The upper bridge drive circuit 100 can output a first upper bridge drive signal UG1 based on the lower bridge turn-on signal LGD and the pulse width modulation signal PWM to control the operation of the upper bridge drive circuit 100.

[0053] [Second Embodiment]

[0054] Please see Figure 2 This is a circuit layout diagram of a power converter with switching components having different safe operating areas according to the second embodiment of the present invention. The similarities to the first embodiment will not be repeated here.

[0055] In this embodiment, the aforementioned lower bridge drive circuit 200 may include a first NOR gate 11, a first AND gate 12, a second NOR gate 13, a second NOT gate 14, a first NOT gate 15, and a second AND gate 16.

[0056] The first input terminal of the first NOR gate 11 is connected to the control terminal of the first upper bridge switch M3. If necessary, a potential conversion circuit 602 and a delay circuit 500 can be provided between the control terminal of the first upper bridge switch M3 and the first input terminal of the first NOR gate 11.

[0057] The first input terminal of the first AND gate 12 is connected to the output terminal of the first NOR gate 11. The second input terminal of the first AND gate 12 is connected to the control terminal of the second lower bridge switch M2. The second input terminal of the first AND gate 12 can receive the second lower bridge drive signal LG2 of the second lower bridge switch M2. The output terminal of the first AND gate 12 can be connected to the control terminal of the first lower bridge switch M1. If necessary, a first buffer 401 can be provided between the output terminal of the first AND gate 12 and the control terminal of the first lower bridge switch M1.

[0058] The first input of the second NOR gate 13 is connected to the output of the first NOR gate 11. The second input of the second NOR gate 13 is connected to the control terminal of the first lower bridge switch M1. The second input of the second NOR gate 13 can receive the first lower bridge drive signal LG1 of the first lower bridge switch M1.

[0059] The output of the second NOR gate 13 can be connected to the input of the second NOT gate 14, and the output of the second NOT gate 14 can be connected to the control terminal of the second lower bridge switch M2. If necessary, a second buffer 402 can be provided between the output of the second NOT gate 14 and the control terminal of the second lower bridge switch M2.

[0060] The input of the first NOT gate 15 is connected to the control terminal of the second lower bridge switch M2. The input of the first NOT gate 15 can receive the second lower bridge drive signal LG2 of the second lower bridge switch M2. The first input of the second AND gate 16 is connected to the output of the second NOR gate 13. The second input of the second AND gate 16 is connected to the output of the first NOT gate 15. The output of the second AND gate 16 is connected to the input of the upper bridge drive circuit 100. The second AND gate 16 can output the lower bridge on signal LGD.

[0061] If necessary, the power converter may also include a delay circuit 700 connected between the output of the second AND gate 16 and the input of the upper bridge drive circuit 100. The delay circuit 700 may be configured to delay the phase of the lower bridge turn-on signal LGD to be output to the upper bridge drive circuit 100.

[0062] [Third Embodiment]

[0063] Please see Figure 3 This is a circuit layout diagram of a power converter with switching components having different safe operating areas according to a third embodiment of the present invention. The similarities to the previous embodiments are not repeated here.

[0064] It is worth noting that, in addition to the first bridge switch M3, the power converter circuit of this embodiment also includes a second bridge switch M4. The safe operating area of ​​the second bridge switch M4 is larger than that of the first bridge switch M3.

[0065] The first terminal of the second bridge switch M4 is coupled to the shared voltage VIN. The control terminal of the second bridge switch M4 is connected to the output terminal of the bridge drive circuit 100. If necessary, a second buffer 302 can be provided between the control terminal of the second bridge switch M4 and the output terminal of the bridge drive circuit 100.

[0066] The second terminal of the second upper bridge switch M4 is connected to the first terminal of the second lower bridge switch M2. The second node LX2 between the second terminal of the second upper bridge switch M4 and the first terminal of the second lower bridge switch M2 is connected to the first node LX1 and the first terminal of the inductor L. The second terminal of the inductor L is connected to the first terminal of the capacitor C, and the second terminal of the capacitor C is grounded. The capacitor C can be connected in parallel with a resistor R.

[0067] It is worth noting that when the lower bridge drive circuit 200 wants to drive the first lower bridge switch M1 to switch from the open state to the closed state, the upper bridge drive circuit 100 first drives the second upper bridge switch M4 with the larger safe operating area to open, and then drives the first upper bridge switch M3 with the smaller safe operating area to open. Conversely, when the lower bridge drive circuit 200 drives the first lower bridge switch M1 to switch from the closed state to the open state, the upper bridge drive circuit 100 first drives the first upper bridge switch M3 with the smaller safe operating area to close, and then drives the second upper bridge switch M4 with the larger safe operating area to close.

[0068] [Fourth Embodiment]

[0069] Please see Figure 4 This is a circuit layout diagram of a power converter with switching components having different safe operating areas according to the fourth embodiment of the present invention. The similarities to the previous embodiments are not repeated here.

[0070] In this embodiment, the aforementioned upper bridge drive circuit 100 may include a first AND gate 31, a second AND gate 32, a first NOR gate 33, a first NOT gate 34, a second NOT gate 35, and a first NAND gate 36.

[0071] The input terminal of the lower bridge drive circuit 200 and the first input terminal of the first AND gate 31 can be connected to the output terminal of an external pulse signal generator (not shown), and receive the pulse width modulation signal PWM from this pulse signal generator. The second input terminal of the first AND gate 31 is connected to the output terminal of the lower bridge drive circuit 200 to receive the lower bridge turn-on signal LGD output by the lower bridge drive circuit 200.

[0072] The first input terminal of the second AND gate 32 is connected to the output terminal of the first AND gate 31. The second input terminal of the second AND gate 32 can be connected to the control terminal of the second upper bridge switch M4 and receive the second upper bridge drive signal UG2 of the second upper bridge switch M4. If necessary, a potential conversion circuit 601 can be set between the output terminal of the first AND gate 31 and the first input terminal of the second AND gate 32.

[0073] The output of the second AND gate 32 can be connected to the control terminal of the first upper bridge switch M3. If necessary, a first buffer 301 can be provided between the output of the second AND gate 32 and the control terminal of the first upper bridge switch M3.

[0074] The first input terminal of the first NOR gate 33 is connected to the output terminal of the first AND gate 31, while the second input terminal of the first NOR gate 33 is connected to the control terminal of the first upper bridge switch M3. The output terminal of the first NOR gate 33 is connected to the input terminal of the first NOT gate 34, while the output terminal of the first NOT gate 34 is connected to the control terminal of the second upper bridge switch M4.

[0075] The input terminal of the second NOT gate 35 is connected to the control terminal of the second lower bridge switch M2. The first input terminal of the first NAND gate 36 is connected to the output terminal of the first NOR gate 33, while the second input terminal of the first NAND gate 36 is connected to the output terminal of the second NOT gate 35.

[0076] The output of the first NAND gate 36 can be connected to the input of the lower bridge driver circuit 200. If necessary, a delay circuit 500 and a potential conversion circuit 602 can be provided between the output of the first NAND gate 36 and the input of the lower bridge driver circuit 200.

[0077] [Fifth Embodiment]

[0078] Please see Figure 5 This is a circuit layout diagram of a power converter with switching components having different safe operating areas according to the fifth embodiment of the present invention.

[0079] In this embodiment, the aforementioned upper bridge switch circuit 100 includes a third AND gate 17, a fourth AND gate 18, a third NOR gate 19, a third NOT gate 20, a fourth NOT gate 21, and a first NAND gate 22, which are the same as the aforementioned first AND gate 31, second AND gate 32, first NOR gate 33, first NOT gate 34, second NOT gate 35, and first NAND gate 36. Therefore, the same content is described above and will not be repeated here.

[0080] In this embodiment, the lower bridge switch circuit 200 includes the aforementioned first NOR gate 11, second NOR gate 13, first NOT gate 15, second NOT gate 14, first AND gate 12, and second AND gate 16. The same content is described above and will not be repeated here.

[0081] In summary, the present invention provides a power converter with switching components having different safe operating areas. It uses two upper bridge switching components or two lower bridge switching components with different safe operating area sizes to achieve the same on-resistance value with a smaller layout area. This reduces the overall size of the power converter chip while still preventing the switching components with poor voltage withstand capability from being damaged due to their inability to withstand excessive current or voltage.

[0082] The above-disclosed content is only a preferred embodiment of the present invention and is not intended to limit the claims of the present invention. Therefore, all equivalent technical changes made based on the description and drawings of the present invention are included in the claims of the present invention.

Claims

1. A power converter with switching components having different safe operating areas, characterized in that, The power converter with switching components having different safe operating areas includes: A first bridge switch, the first terminal of the first bridge switch being coupled to a shared voltage; The first lower bridge switch has its first terminal connected to the second terminal of the first upper bridge switch, and the second terminal of the first lower bridge switch is grounded. The second lower bridge switch has its first terminal connected to a first node between the second terminal of the first upper bridge switch and the first terminal of the first lower bridge switch. The second terminal of the second lower bridge switch is grounded. The first node is connected to the first terminal of an inductor. The second terminal of the inductor is connected to the first terminal of a capacitor. The second terminal of the capacitor is grounded. An upper bridge drive circuit, wherein the output terminal of the upper bridge drive circuit is connected to the control terminal of the first upper bridge switch through a first buffer, and is configured to drive the first upper bridge switch to open or close. as well as A lower bridge drive circuit is connected to the control terminal of the first lower bridge switch and configured to drive the first lower bridge switch to open or close. The safe operating area of ​​the second lower bridge switch is larger than the safe operating area of ​​the first lower bridge switch. Wherein, the first upper bridge switch and the first lower bridge switch are complementary in switching; Wherein, after the lower bridge drive circuit closes the first lower bridge switch, the lower bridge drive circuit closes the second lower bridge switch; Specifically, before the lower bridge drive circuit turns on the first lower bridge switch, the lower bridge drive circuit turns on the second lower bridge switch. The lower bridge drive circuit includes a first NOR gate, a second NOR gate, a second NOT gate, and a first AND gate. The first input of the first NOR gate is connected to the output of a delay circuit. The input of the delay circuit is connected to the output of a potential conversion circuit. The input of the potential conversion circuit is connected to the control terminal of the first upper bridge switch. The second input of the first NOR gate is connected to the output of a pulse signal generator. The two inputs of the first AND gate are respectively connected to the output of the first NOR gate and the control terminal of the second lower bridge switch. The output of the first AND gate is connected to the control terminal of the first lower bridge switch through another first buffer. The two inputs of the second NOR gate are respectively connected to the output of the first NOR gate and the control terminal of the first lower bridge switch. The output of the second NOR gate is connected to the input of the second NOT gate. The output of the second NOT gate is connected to the control terminal of the second lower bridge switch through a second buffer.

2. The power converter with switching components having different safe operating areas according to claim 1, characterized in that, The power converter with switching components having different safe operating areas further includes a resistor, a first end of which is connected to a first end of the capacitor and a second end of the inductor, the second end of which is grounded, and the output node between the first end of the capacitor and the second end of the inductor is the output terminal of the power converter.

3. The power converter with switching components having different safe operating areas according to claim 1, characterized in that, The lower bridge drive circuit includes a first NOT gate and a second AND gate. The input terminal of the first NOT gate is connected to the control terminal of the second lower bridge switch. The two input terminals of the second AND gate are respectively connected to the output terminal of the second NOR gate and the output terminal of the first NOT gate. The input terminal of the upper bridge drive circuit is connected to the output terminal of the second AND gate through another delay circuit, and the input terminal of the upper bridge drive circuit is connected to the output terminal of the pulse signal generator.

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