Primary side integrated circuit module of power supply

Abstract

The present invention relates to a primary-side integrated circuit module of a power supply, comprising a control unit, a rectifier unit, and a first switch element arranged in a package body; two power input terminals, a positive power output terminal, and a negative power output terminal of the rectifier unit are respectively electrically connected to two AC power pins and a DC power pin and a ground pin on the package body; a first end and a second end of the first switch element are respectively connected to the switch element pins of the package body, a first control output terminal of the control unit is electrically connected to the control terminal of the first switch element, and a current detection input terminal of the control unit is connected to one of the switch element pins on the package body. The primary-side main transistors and circuits of the power supply are integrated through packaging technology, thereby reducing the number of components of the overall circuit, simplifying the design, and improving the reliability of the overall circuit.

Description

Technical Field

[0001] The invention relates to a circuit module, in particular to a primary side integrated circuit module of a power supply. Background Art

[0002] A power converter is a basic circuit that most electronic devices must be equipped with. The power converter converts the voltage provided by a fixed external power source into the rated input voltage of the load circuit of the electronic device for use by the electronic device. Fig. 9 The figure shows a common power converter, which generally includes a primary circuit 41, a secondary circuit 42, and a transformer 43. The primary circuit 41 includes an AC input terminal ACinput, a rectifier 411, a control unit 412, a switch element 413, and a buffer circuit 414. The DC output terminal DCoutput of the secondary circuit 42 supplies power to a load circuit. In a voltage converter with high voltage and high frequency switching, high-frequency noise generated by the parasitic and stray elements of the circuit itself and each circuit element is inevitable. The high-frequency noise may make the output unstable or cause damage to the electronic components. Therefore, how to reduce the generation of high-frequency noise by optimizing the component placement and wiring on the circuit board is a necessary consideration in circuit design. Furthermore, when the number of components in the circuit is large or the electrical connection is complex, and the area size of the circuit board is limited by the overall device specifications, it is often difficult to achieve an excellent wiring design to reduce the interference of high-frequency noise, and the difficulty of technicians in welding components will also increase, resulting in a decrease in the yield of the circuit product. Therefore, the power converter assembly in the prior art needs to be further improved. Summary of the invention

[0003] Therefore, the main purpose of the present invention is to provide a primary-side integrated circuit module of a power supply, which integrates the main semiconductor components of the primary side of the power supply into one body to reduce the number of components and pins, thereby improving the reliability of the circuit module and reducing the welding cost.

[0004] The main technical means adopted to achieve the above-mentioned purpose is to make the primary side integrated circuit module of the above-mentioned power supply include:

[0005] A package body is provided with two AC power pins, a DC power pin, and two switch element pins;

[0006] A rectifier unit is disposed in the package body, the rectifier unit has two power input terminals, a positive power output terminal and a negative power output terminal, the two power input terminals are electrically connected to the two AC power pins on the package body respectively; the positive power output terminal is electrically connected to the DC power pin of the package body;

[0007] A first switch element, disposed in the package, the first switch element having a first end, a second end and a control end; wherein the first end and the second end are electrically connected to two switch element pins of the package respectively;

[0008] A control unit is arranged in the package body, and the control unit has a first control output terminal and a current detection terminal; the first control output terminal is electrically connected to the control terminal of the first switch element, and the current detection terminal is connected to one of the switch element pins on the package body.

[0009] The integrated circuit module is provided as a primary side main circuit connection of a power supply converter. The rectifier unit receives an AC power supply through the two AC power pins and outputs it from the positive power output terminal after rectification. The positive power output terminal is connected to one end of the primary winding of a transformer, and the negative power output terminal is electrically connected to a ground terminal through the ground pin. One of the two switch element pins is connected to the other end of the primary winding of the transformer, and the other switch element pin is electrically connected to the ground terminal through a resistor. The current detection terminal of the control unit receives a detection signal by being electrically connected to the switch element pin, and generates a first control signal accordingly, and outputs the first control signal from the first control output terminal. The first switch element receives the first control signal through the control terminal and adjusts a conduction period, so that the secondary winding of the transformer provides a stable output voltage at an output terminal.

[0010] The integrated circuit module of the present invention integrates the main circuit elements of the primary side of a power supply, including a rectifier unit, a control unit and a switch element. By modularizing the main transistor elements and integrating them through packaging technology, the circuit stability is high compared to the power circuit formed by electrically connecting each circuit element separately. The integrated circuit module is small in size and low in cost. For the overall power supply circuit, the number of external circuit elements is greatly reduced, so that the arrangement of other circuit elements of the voltage conversion circuit is more spacious, with better circuit design flexibility, and reduces the circuit welding cost, and also reduces the probability of poor component connection, thereby improving the stability and yield of the overall voltage conversion circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 FIG. 4 is a block diagram of a primary-side integrated circuit module of a power supply of the present invention.

[0012] Figure 2 It is a schematic diagram of an application circuit of a primary-side integrated circuit module of a power supply of the present invention.

[0013] Figure 3FIG. 4 is a block diagram of a first preferred embodiment of a primary-side integrated circuit module of a power supply of the present invention.

[0014] Figure 4 FIG. 4 is a block diagram of a second preferred embodiment of a primary-side integrated circuit module of a power supply of the present invention.

[0015] Figure 5 FIG. 4 is a block diagram of a third preferred embodiment of a primary-side integrated circuit module of a power supply of the present invention.

[0016] Figure 6 FIG. 4 is a block diagram of a second preferred embodiment of a primary-side integrated circuit module of a power supply of the present invention.

[0017] Figure 7 Schematic diagram of the fourth and fifth preferred embodiments of the primary-side integrated circuit module of the power supply of the present invention.

[0018] Figure 8 It is a schematic diagram of an application circuit of a primary-side integrated circuit module of a power supply of the present invention.

[0019] Fig. 9 FIG. 1 is a circuit diagram of a conventional power supply. DETAILED DESCRIPTION

[0020] The following is a detailed description of the technical means used by the present invention to achieve the intended purpose of the invention with reference to the drawings and preferred embodiments of the present invention.

[0021] The present invention provides a primary-side integrated circuit module of a power supply, comprising a package 10, a rectifier unit 21, a first switch element 22 and a control unit 23. The rectifier unit 21, the first switch element 22 and the control unit 23 are all arranged in the package 10. The package 10 is provided with two AC power pins 11, 12, a DC power pin 13, a ground pin 14, and two switch element pins 15, 16. The rectifier unit 21 has two power input terminals, a positive power output terminal and a negative power output terminal, and the two power input terminals are respectively electrically connected to the two AC power pins 11, 12 on the package 10; the positive power output terminal is electrically connected to the DC power pin 13 of the package 10, and the negative power output terminal is electrically connected to the ground pin 14. The first switch element 22 has a first end, a second end and a control end, wherein the first end and the second end are respectively electrically connected to the two switch element pins of the package 10. The control unit 23 has a first control output terminal and a current detection terminal, wherein the first control output terminal is electrically connected to the control terminal of the first switch element 22, and the current detection terminal is electrically connected to one of the switch element pins 16 on the package body 10. Preferably, the rectifier unit 21 is a full-bridge rectifier. Preferably, the first switch element 22 is a metal oxide semi-conductor field effect transistor (MOSFET), wherein the first terminal and the second terminal are respectively the drain and the source of the metal oxide semi-conductor field effect transistor, and the control terminal is the gate of the metal oxide semi-conductor field effect transistor.

[0022] See also Figure 1 and Figure 2 As shown, the integrated circuit module is provided as a primary side main circuit connection of a power supply converter. The rectifier unit 21 receives an AC power source AC1, AC2 from the two AC power pins 11, 12 and outputs it from the positive power output terminal after rectification. The positive power output terminal is connected to one end of the primary winding of a transformer 30, and the negative power output terminal is electrically connected to a ground terminal via the ground pin 14. One of the two switch element pins 15, 16 is connected to the other end of the primary winding N1 of the transformer 30, and the other switch element pin 16 is electrically connected to the ground terminal via a resistor. The current detection terminal of the control unit 23 is electrically connected to the switch element pin 16 to receive a detection signal, thereby generating a first control signal. A first control signal is output from the first control output terminal, and the first switch element 22 receives the first control signal through the control terminal and generates a conduction cycle, so that the secondary winding N2 of the transformer 30 provides an output terminal Vo with a stable output voltage.

[0023] The primary side integrated circuit module of the power supply of the present invention integrates the main circuit elements of a power supply, including a rectifier unit 21, a control unit 23 and a first switch element 22. By modularizing the main transistor elements and integrating them through packaging technology, the circuit stability is high compared to the power circuit formed by electrically connecting each circuit element separately. The integrated circuit module is small in size and low in cost. For the overall power supply circuit, the number of external circuit elements is greatly reduced, so that the arrangement of other circuit elements of the voltage conversion circuit is more spacious, with better circuit design flexibility, and reduces the circuit welding cost, and also reduces the probability of poor component connection, thereby improving the stability and yield of the overall voltage conversion circuit.

[0024] See also Figure 3 As shown, in a first preferred embodiment of the present invention, a buffer circuit 24 is further provided in the package body 10, and the buffer circuit 24 has a first node and a second node, and the first node and the second node are electrically connected to the first end and the second end of the first switch element 22 respectively.

[0025] In the preferred embodiment, a buffer circuit 24 connected in parallel with the first switch element 22 is further included to limit the voltage rise surge of the first switch element 22 when the first switch element 22 is switched to a cut-off state, and provide an alternative path for the current of the primary winding.

[0026] See also Figure 4 As shown, in a second preferred embodiment of the present invention, the package body 10 further includes a buffer circuit pin 16A, and the first node of the buffer circuit 24 is electrically connected to the first end of the first switch element 22, and the second node of the buffer circuit 24 is electrically connected to the buffer circuit pin 16A.

[0027] The buffer circuit pin 16A provides the power supply circuit with further circuit design flexibility. When the buffer circuit 24 pin is electrically connected to the power input end of the primary winding, that is, electrically connected to the DC power pin 13 of the package 10, the buffer circuit 24 is connected in parallel with the primary winding, providing a current path for the primary winding when the first switch element 22 is turned off, thereby avoiding voltage surges on the primary winding due to sudden current cutoff. In other words, the circuit designer only needs to short-circuit the buffer circuit pin 16A and the switch element pin 16, so that the buffer circuit 24 inside the package 10 can be connected in parallel with the first switch element 22, that is, forming an equivalent circuit of the buffer circuit in the first preferred embodiment of the present invention.

[0028] See also Figure 5 and Figure 6As shown, in the first and second preferred embodiments, preferably, the buffer circuit 24 is provided with a diode D1, a resistor R1 and a capacitor C connected in series in sequence between the first node and the second node. When the first switch element 22 is turned off, the leakage current of the primary side flows through the buffer circuit 24, so that the voltage stress of the first switch element 22 can be reduced.

[0029] See also Figure 7 As shown, preferably, the package 10 is further provided with a control unit power pin 17, and the package 10 is further provided with a second switch element 25, the second switch element 25 has a first end, a second end and a control end, the first end of the second switch element 25 is connected to the positive power output end of the rectifier unit 21 through a resistor R1; the control unit 23 has a second control output end and a power input end, the second control output end is electrically connected to the control end of the second switch element 25, and the power input end is electrically connected to the second end of the second switch element 25 and the control unit power pin 17 of the package 10. Please refer to Figure 8 As shown, the second switch element 25 is a normally on semiconductor element. Before an alternating current is input to the two AC power pins 11 and 12, the second switch element 25 remains turned on. After the alternating current is input, current flows through the resistor R2 and the second switch element 25 to charge the capacitor Cv. When the voltage on the capacitor Cv is established, the control unit 23 outputs a signal to turn off the second switch element 25.

[0030] Please see again Figure 7 As shown, in a third preferred embodiment of the present invention, a first auxiliary power pin 18 is further provided on the package body 10, and a diode D2 is further provided in the package body 10, and the two ends of the diode D2 are electrically connected to the first auxiliary power pin 18 of the package body 10 and the control unit power pin 17 respectively.

[0031] As shown in FIG8 , the first auxiliary power pin 18 supplies power to a first auxiliary winding N1 ′ of the power supply circuit. The first auxiliary winding N1 ′ is coupled to the primary winding N1 of the power supply circuit.

[0032] Please see again Figure 7 As shown, in a fourth preferred embodiment of the present invention, the package 10 has a second auxiliary power pin 19, and a low voltage dropout regulator 26 is further provided in the package 10. An input end of the low voltage dropout regulator 26 is electrically connected to the second auxiliary power pin 19, and an output end of the low voltage dropout regulator 26 is electrically connected to the power input end of the control unit 23.

[0033] See also Figure 8 As shown, the second auxiliary power pin 19 supplies power to a second auxiliary winding N1″ of the power supply circuit. Preferably, the first auxiliary winding N1′ is a center-tapped output terminal of the second auxiliary winding N1″. That is, the voltage of the first auxiliary power pin 18 is lower than the voltage of the second auxiliary power pin 19 at a fixed ratio.

[0034] For example, when the rated input voltage of the power input terminal of the control unit 23 is 12V, and the winding ratio of the first auxiliary winding N1' to the second auxiliary winding N1" is 1:6. When the voltage of the second auxiliary winding N1" is about 12V, since the voltages of the input terminal and the output terminal of the low-voltage dropout regulator 26 are similar, the low-voltage dropout regulator 26 is activated and turned on, performs voltage regulation and outputs a stable 12V from the output terminal to the power input terminal of the control unit 23. At this time, the voltage of the first auxiliary winding N1' is much lower than the 12V according to the winding ratio, and the diode D2 is reverse biased and does not conduct.

[0035] When the voltage of the second auxiliary winding N1' rises to a value much higher than 12V, for example, 72V, due to the large voltage difference between the input and output ends of the low voltage dropout regulator 26, the low voltage dropout regulator 26 does not operate and forms an open circuit. At this time, the voltage of the first auxiliary winding N1' is about 12V according to the winding ratio, and the diode D2 is forward biased. The diode D2 is turned on and outputs the 12V first winding output voltage to the power input end of the control unit 23. Accordingly, even if the voltage variation range of the output end Vo is large, the input voltage received by the control unit 23 can still stably maintain a smaller variation range, which can improve the problem of excessive power consumption of the auxiliary power supply under a wide output range.

[0036] Please continue reading Figure 7 and Figure 8 As shown, in a fifth preferred embodiment of the present invention, the package body 10 has a feedback voltage pin 20, and the control unit 23 further includes a feedback voltage input terminal, and the feedback voltage input terminal is electrically connected to the feedback voltage pin 20. The feedback voltage pin 20 is used to receive a divided voltage of the second auxiliary winding N1", and the control unit 23 receives the divided voltage of the second auxiliary winding N1" via the feedback voltage input terminal as a primary-side feedback reference voltage, and the control unit 23 generates the first control signal according to the feedback reference voltage.

[0037] The above is only a preferred embodiment of the present invention, and does not limit the present invention in any form. Although the present invention has been disclosed as a preferred embodiment as above, it is not used to limit the present invention. Any technician familiar with this profession can make some changes or modifications to equivalent embodiments of equivalent changes using the technical contents disclosed above without departing from the scope of the technical solution of the present invention. However, any simple modification, equivalent change and modification made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. A primary-side integrated circuit module of a power supply, characterized in that: include: A package body is provided with two AC power pins, a DC power pin, a ground pin and two switch element pins; a rectifier unit, disposed in the package, the rectifier unit having two power input terminals, a positive power output terminal and a negative power output terminal, the two power input terminals are electrically connected to two AC power pins on the package respectively, the positive power output terminal is electrically connected to the DC power pin of the package; the negative power output terminal is electrically connected to the ground pin of the package; A first switch element, disposed in the package, the first switch element having a first end, a second end and a control end; wherein the first end and the second end are electrically connected to two switch element pins of the package respectively; a control unit, disposed in the package, the control unit having a first control output terminal and a current detection terminal; the first control output terminal is electrically connected to the control terminal of the first switch element, and the current detection terminal is connected to one of the switch element pins on the package; A buffer circuit is further provided in the package, the buffer circuit having a first node and a second node, the first node and the second node being electrically connected to the first end and the second end of the first switch element respectively; The buffer circuit has a diode, a resistor and a capacitor connected in series in sequence between a first node and a second node.

2. The primary-side integrated circuit module of the power supply as claimed in claim 1, wherein: The package further includes a buffer circuit pin, a first node of the buffer circuit is electrically connected to the first end of the first switch element, and a second node of the buffer circuit is electrically connected to the buffer circuit pin.

3. The primary-side integrated circuit module of the power supply as claimed in claim 1, wherein: A control unit power pin is provided on the package body, and a second switch element is further provided in the package body, the second switch element has a first end, a second end and a control end, and the first end of the second switch element is connected to the positive power output end of the rectifier unit through a resistor; The control unit has a second control output terminal and a power input terminal. The second control output terminal is electrically connected to the control terminal of the second switch element. The power input terminal is electrically connected to the second terminal of the second switch element and the power pin of the control unit.

4. The primary-side integrated circuit module of the power supply as claimed in claim 3, wherein: The package body is provided with a first auxiliary power pin, and the package body is further provided with a diode, and two ends of the diode are electrically connected to the first auxiliary power pin and the power pin of the package body respectively.

5. The primary-side integrated circuit module of the power supply as claimed in claim 4, wherein: The package body is provided with a second auxiliary power pin, and the package body is further provided with a low voltage dropout regulator; wherein, An input end of the low voltage dropout regulator is electrically connected to the second auxiliary power pin, and an output end of the low voltage dropout regulator is electrically connected to the power input end of the control unit.

6. The primary-side integrated circuit module of the power supply as claimed in claim 1, wherein: The package body is provided with a feedback voltage pin; The control unit further includes a feedback voltage input terminal, and the feedback voltage input terminal is electrically connected to the feedback voltage pin.

7. The primary-side integrated circuit module of the power supply as claimed in claim 1, wherein: The first switch element is a metal oxide semi-conductor field effect transistor, the first end and the second end are respectively a drain and a source of the metal oxide semi-conductor field effect transistor, and the control end is a gate of the metal oxide semi-conductor field effect transistor.

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