A plastic package patch ideal diode

Abstract

The utility model discloses a kind of ideal diodes of plastic package patch, include frame, the frame has three electrodes, using soft solder sintering connection MOS chip and ceramic copper-clad plate on electrode OUT;First bottom plate electrode on copper-clad ceramic plate and the electrode of back are connected through via, and control chip placement area uses soft solder sintering connection control IC;The VDD of control chip surface and VOUT electrode are connected to first bottom plate electrode through gold wire bonding, and electrode OUT forms electrical connection;The GND electrode of control chip surface is connected to second bottom plate electrode through gold wire bonding, and second bottom plate electrode and electrode GND use aluminium wire bonding;The GATE electrode of control chip surface is connected to third bottom plate electrode through gold wire bonding, and third bottom plate electrode and the gate PAD of MOS chip use aluminium wire bonding;The VIN electrode of control chip surface is connected to fourth bottom plate electrode through gold wire bonding, and fourth bottom plate electrode and electrode IN use aluminium wire bonding.The overall structure of the utility model uses copper frame plus plastic package material, and cost is controllable.

Description

Technical Field

[0001] This utility model relates to hybrid integrated circuit devices, specifically a plastic-encapsulated surface mount ideal diode. Background Technology

[0002] Schottky diodes are widely used in various power systems to provide reverse current protection during input power failures, to increase power capacity in parallel power supplies, or to provide backup power. However, the large forward voltage drop and rapidly increasing reverse leakage current of Schottky diodes lead to significant power losses and reduced system efficiency. MOSFETs (Field-Effect Transistors) offer advantages over traditional Schottky diodes, such as low conduction losses and extremely low reverse leakage current. Therefore, combining a driver chip with a MOSFET can yield an ideal diode product with ultra-low on-state voltage drop and negligible reverse leakage current, significantly reducing power losses in high-current scenarios.

[0003] The existing alternative to Schottky diodes involves an ideal diode controller and a low on-resistance MOSFET connected electrically via a PCB board or other circuitry to achieve the function of an ideal diode. This approach requires a larger area, increases PCB manufacturing costs, and necessitates consideration of the selection of a low on-resistance MOSFET, thus increasing the system design workload. Utility Model Content

[0004] The technical problem to be solved by this invention is to provide a plastic-encapsulated surface mount (TO-263) ideal diode for driving a low on-resistance MOSFET with an ideal diode controller, so as to achieve low conduction loss.

[0005] The technical solution of this utility model is: a plastic-encapsulated surface mount ideal diode, with the following specific structure:

[0006] The frame is a copper frame body, including three electrodes: OUT, IN, and GND. The MOS chip and the copper-clad ceramic substrate are sintered together using solder on electrode OUT. The copper-clad ceramic substrate includes a control chip placement area, a first base plate electrode, a second base plate electrode, a third base plate electrode, and a fourth base plate electrode. The first base plate electrode is connected to the electrode on the back side via a through-hole and is considered as one electrode. The control chip placement area is sintered together with the control IC using solder, providing mechanical support. The VDD and VOUT electrodes on the surface of the control chip are connected to the first base plate electrode via 18µm gold wire bonding, and to electrode OUT... The UT electrode forms an electrical connection; the GND electrode on the surface of the control chip is bonded to the second base plate electrode via an 18µm gold wire, and then the second base plate electrode and the GND electrode are bonded to form an electrical connection via a 100µm aluminum wire; the GATE electrode on the surface of the control chip is bonded to the third base plate electrode via an 18µm gold wire, and then the third base plate electrode and the gate PAD of the MOS chip are bonded to form an electrical connection via a 100µm aluminum wire; the VIN electrode on the surface of the control chip is bonded to the fourth base plate electrode via an 18µm gold wire, and then the fourth base plate electrode and the IN electrode are bonded to form an electrical connection via a 100µm aluminum wire.

[0007] The principle of this invention is as follows: An ideal diode control chip and a low on-resistance power MOSFET are electrically connected via a copper-clad ceramic plate and three different bonding wires to achieve their overall function. The control chip changes the output drive voltage by detecting the voltage difference across the source and drain of the MOSFET to control the MOSFET's turn-on and turn-off. The power consumption of the entire control section is very low; therefore, the control section is connected to the input and output using gold ball bonding and fine aluminum wire wedge bonding. The power section, which is the source and drain of the MOSFET, needs to carry a considerable current; therefore, thick aluminum wire bonding and solder sintering are used to connect them to reduce losses. This package uses a copper frame and molding compound structure, making the cost controllable.

[0008] This invention integrates the functions of an ideal diode through a special design of the copper-clad ceramic plate and bonding wires. It also incorporates the aluminum wire resistance connecting the source and drain sides into the control range of the controller, ultimately realizing an ideal diode with three ports: power input, power output, and common ground. Compared with traditional Schottky diode or ideal diode controller solutions, this invention can reduce conduction losses while further reducing system or PCB area. It also reduces the conduction losses of the device at low currents, achieving higher power density. Due to its plastic packaging structure, this invention has low cost and high cost-effectiveness. Attached Figure Description

[0009] Figure 1 This is the circuit schematic diagram of this utility model;

[0010] Figure 2 This is a schematic diagram of the front and back structures of the copper-clad ceramic plate of this utility model;

[0011] Figure 3 This is a schematic diagram of the internal overall structure of the copper-clad ceramic plate of this utility model;

[0012] Figure 4 This is a view of the overall shape of the present invention after packaging.

[0013] In the diagram: 1-Frame, 2-Control IC, 3-MOS chip, 4-Copper-clad ceramic plate; 5-Control chip placement area, 6-First base plate electrode, 7-Second base plate electrode; 8-Third base plate electrode; 9-Fourth base plate electrode; 10-Through hole; 11-Electrode OUT, 12-Electrode IN, 13-Electrode GND. Detailed Implementation

[0014] A plastic-encapsulated surface mount ideal diode includes a frame, wherein the frame 1 is a copper frame body and includes three electrodes: electrode OUT, electrode IN, and electrode GND.

[0015] The MOS chip 3 and the ceramic copper-clad board 4 are sintered together using soft solder on electrode OUT. The ceramic copper-clad board 4 includes a control chip placement area 1, a first base electrode 6, a second base electrode 7, a third base electrode 8, and a fourth base electrode 9. The first base electrode 6 is connected to the electrode on the back side via a through-hole 10, and is considered as one electrode. The control chip placement area 5 is sintered together with the control IC 2 using soft solder, providing mechanical support. The VDD and VOUT electrodes on the surface of the control chip are connected to the first base electrode 6 via 18µm gold wire bonding, forming an electrical connection with electrode OUT. The surface GND electrode is bonded to the second base plate electrode 7 via an 18µm gold wire, and then the second base plate electrode 7 and the GND electrode are electrically connected using a 100µm aluminum wire. The surface GATE electrode of the control chip is bonded to the third base plate electrode 8 via an 18µm gold wire, and then the third base plate electrode 8 is electrically connected to the gate PAD of the MOS chip 3 using a 100µm aluminum wire. The surface VIN electrode of the control chip is bonded to the fourth base plate electrode 9 via an 18µm gold wire, and then the fourth base plate electrode 9 is electrically connected to the IN electrode using a 100µm aluminum wire.

[0016] The above-mentioned packaging method for a plastic-encapsulated surface mount ideal diode includes the following steps:

[0017] First, a sintering process is performed. The frame 1 is placed on a heating stage. The drain end of the MOS chip 3 and the bottom of the copper-clad ceramic plate 4 are placed on the electrode OUT of the frame 1 using soft solder. Then, the control IC 2 is placed on the control chip placement area 5 on the copper-clad ceramic plate 4 using soft solder. Finally, the sintering process is used to complete the welding of all components.

[0018] Next is the bonding process. Using 18µm gold ball bonding, electrical connections related to the control chip are completed, including the electrical connections between the VDD and VOUT electrodes and the first substrate electrode 6, the GND electrode and the second substrate electrode 7, the GATE electrode and the third substrate electrode 8, and the VIN electrode and the fourth substrate electrode 9. Using 100µm aluminum wire wedge bonding, the electrical connections between the second substrate electrode 7 and the electrode sheet (GND), the third substrate electrode 8 and the gate PAD of the MOS chip 3, and the fourth substrate electrode 9 and the electrode sheet (IN) are completed. Finally, using 380µm aluminum wire wedge bonding, the electrical connections between the source of the MOS chip 3 and the electrode sheet (IN) are completed.

[0019] Finally, molding compound is used to complete the curing and cutting of the reinforcing bars.

[0020] This packaging structure is a plastic surface mount package, which realizes the ideal diode function through encapsulation. It is mainly used in various power supply systems or automatic control systems. Its features include compact product structure, convenient surface mount packaging, fast turn-off response time, wide voltage operating range, extremely short internal electrode connection distance, very small parasitic parameters, high power density, internal bonding wire resistance adjustable by the controller, and lower cost, making it cost-effective.

Claims

1. A plastic encapsulated chip ideal diode, characterized by, The system includes a frame (1), which is a copper frame and includes three electrodes: electrode OUT, electrode IN, and electrode GND. A MOS chip (3) and a copper-clad ceramic plate (4) are sintered together using solder on electrode OUT. The copper-clad ceramic plate (4) includes a control chip placement area (5), a first base plate electrode (6), a second base plate electrode (7), a third base plate electrode (8), and a fourth base plate electrode (9). The first base plate electrode (6) is connected to the electrode on the back side via a through-hole (10) and is considered as one electrode. The control chip placement area is sintered together with a control IC (2) using solder to provide mechanical support. The VDD and VOU on the surface of the control chip are... The T electrode is connected to the first base plate electrode (6) by gold wire bonding, forming an electrical connection with the electrode OUT; the GND electrode on the surface of the control chip is connected to the second base plate electrode (7) by gold wire bonding, and then the second base plate electrode (7) and the electrode GND are electrically connected by aluminum wire bonding; the GATE electrode on the surface of the control chip is connected to the third base plate electrode (8) by gold wire bonding, and then the third base plate electrode (8) is electrically connected to the gate PAD of the MOS chip (3) by aluminum wire bonding; the VIN electrode on the surface of the control chip is connected to the fourth base plate electrode (9) by gold wire bonding, and then the fourth base plate electrode (9) and the electrode IN are electrically connected by aluminum wire bonding.

2. The plastic encapsulated chip ideal diode of claim 1, wherein, The gold wire is 18µm gold wire.

3. The plastic encapsulated chip ideal diode of claim 1, wherein, The aluminum wire is a 100µm aluminum wire.

4. The plastic encapsulated chip ideal diode of claim 1, wherein, The electrical connection between the source of the MOS chip (3) and the electrode plate, i.e., the electrode IN, is made by 380um aluminum wire wedge soldering.

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