CN207966978U - Two-piece type synchronous rectification diode with closed notch - Google Patents

Abstract

The utility model discloses the two-piece type synchronous rectification diodes with closed notch, including the first frame, MOSFET chips, control IC chip, the second frame, built-in capacitance, there are two external pins for second frame, second frame is equipped with closed notch, control IC chip is fixed on the second frame, the external terminal of built-in capacitance connects on the second frame, and inscribed line end is located at closed indentation, there；First frame is set there are one external pin, and MOSFET chips are fixed on the first frame；It is connected by bonding line between the MOSFET chips, control IC chip, built-in capacitance.Two-piece type synchronous rectification diode with closed notch optimizes structure, and area can be utilized by integrating PAD, eliminated and easily caused undesirable fault of construction.

Description

Two-piece synchronous rectifier diode with enclosed gap

technical field

The utility model relates to the field of chip production, in particular to a two-piece synchronous rectification diode with a closed gap.

Background technique

The structural principle of the Schottky rectifier is very different from that of the PN junction rectifier. Usually, the PN junction rectifier is called a junction rectifier, and the metal-semiconductor rectifier is called a Schottky rectifier. The existing rectification element Schottky diode has the problem of large rectification loss and low conversion efficiency.

Synchronous rectification diode is composed of control IC, power MOSFET and its auxiliary circuit, so as to realize the new technology of low loss rectification. The existing synchronous rectification structural components are clumsy and inconvenient, large in size, difficult to dissipate heat, and thin and repetitive pins, which cause certain troubles for installation and use.

Utility model content

In order to solve the deficiencies of the prior art, the utility model proposes a two-piece synchronous rectification diode with a closed gap, which optimizes the structure, integrates the available area of the PAD, and eliminates structural defects that are likely to cause defects.

The utility model adopts the following technical solutions:

A two-piece synchronous rectification diode with a closed gap, including a first frame, a MOSFET chip, a control IC chip, a second frame, and a built-in capacitor. The second frame has two external pins, and the second frame is provided with The closed gap, the control IC chip is fixed on the second frame, the external terminal of the built-in capacitor is connected to the second frame, and the internal terminal is located at the closed gap; the first frame has an external pin, and the MOSFET chip is fixed on the second frame. On a frame; the MOSFET chip, the control IC chip, and the built-in capacitor are connected through bonding wires.

Further, the built-in capacitor is an MLCC capacitor.

Further, the first frame and the second frame are copper alloy frames.

Further, the first frame, the MOSFET chip, the control IC chip, the second frame, and the built-in capacitor are welded and molded by bonding wires, and then packaged in a plastic package to form an integral synchronous rectification diode.

Furthermore, the external pin of the first frame is the cathode of the synchronous rectification diode, and the external pin of the second frame is the anode of the synchronous rectification diode.

The beneficial technical effect obtained by adopting the above technical scheme is:

Complying with the development trend of thinner, smaller and surface-mounted semiconductor rectifier devices, the compact synchronous rectification structure and its manufacturing method developed by this utility model eliminate structural defects that are likely to cause defects through component integration and optimization of the structure. The purpose of reducing the size of components, simplifying the installation process, and improving heat dissipation is achieved, so the synchronous rectification structure has great advantages.

The two-piece synchronous rectifier diode with a closed gap optimizes the structure and integrates the available area of the PAD (the pad placement area in the PCB or printed circuit board), eliminating structural defects that may cause defects.

Punch out a closed gap on the second frame by punching to accommodate the MLCC capacitor. This method ensures the integrity of the frame and improves the bonding force between the plastic package and the frame, avoiding the impact of the colloid on the frame during the plastic sealing process, and Integrating the second frame can make use of the PAD area, providing space for bonding wires and expansion in the later stage.

Description of drawings

Figure 1 is a schematic diagram of the structure of a two-piece synchronous rectification diode with a closed gap.

Fig. 2 is a schematic diagram of the manufacturing process of a two-piece synchronous rectification diode with a closed gap.

Figure 3 shows the package dimensions of a two-piece synchronous rectifier diode product with a closed gap.

Figure 4 is a schematic diagram of the internal control of a two-piece synchronous rectifier diode product with a closed gap.

Fig. 5 is the application circuit diagram of the forward rectification of the utility model.

Fig. 6 is a circuit diagram of a reverse rectification application of the utility model.

In the figure, 1. first frame; 2. MOSFET chip; 3. control IC chip; 4. second frame; 5. built-in capacitor.

Detailed ways

The specific embodiment of the utility model is further described in conjunction with accompanying drawing 1 to 6:

Example 1:

As shown in Figure 1, the two-piece synchronous rectification diode with a closed gap includes a first frame 1, a MOSFET chip 2, a control IC chip 3, a second frame 4, and a built-in capacitor 5, and the second frame has two External pins, the second frame is provided with a closed gap, the control IC chip is fixed on the second frame, the external terminal of the built-in capacitor is connected to the second frame, and the internal terminal is located at the closed gap; the first frame has An external pin, the MOSFET chip is fixed on the first frame; the MOSFET chip, the control IC chip, and the built-in capacitor are connected through bonding wires.

The built-in capacitors are MLCC capacitors. The first frame and the second frame are copper alloy frames. The first frame 1, the MOSFET chip 2, the control IC chip 3, the second frame 4, and the built-in capacitor 5 are welded and formed by bonding wires, and then packaged in a plastic package to form an integral synchronous rectification diode.

Use the punching method to punch out the closed gap on the second frame to accommodate the MLCC capacitor. This method ensures the integrity of the frame, improves the bonding force between the plastic package and the frame, and avoids the glue on the frame during the plastic sealing process. The impact effect, and the integration of the second frame can use the PAD area, which provides space for later bonding wires and expansion.

Example 2:

Two-piece synchronous rectifier diodes with closed gaps are fabricated using the following procedure:

(1) Raw material preparation: Customize the copper alloy frame of the first frame and the second frame (closed gap type), prepare MOSFET chips, control IC chips, and built-in capacitors, and inspect the appearance and electrical defects before device installation.

(2) Chip mounting and welding: through the automatic welding process, the MOSFET chip is combined with the first frame, the control IC chip and the built-in capacitor are bonded to the second frame, and welded and formed.

(3) Wire bonding: each device is bonded by an automatic wire bonding machine to form a circuit.

(4) Plastic sealing and molding: plastic sealing and molding of the bonded devices through a compression molding process.

(5) Electroplating and dicing: Remove residual glue, tin-plate pins (if the frame is treated with nickel-palladium-gold or nickel-gold surface, tin-plating is not required), baking, and dicing.

(6) Printing test: After the diced components are tested by the testing machine, they are printed and packed into boxes.

(7) Visual inspection: observe under a microscope, and remove bad appearance.

(8) Packaging and storage.

A two-piece synchronous rectifier diode with a closed gap as shown in FIG. 3 is manufactured by the above process.

Example 3:

As described in Embodiment 1, for a two-piece synchronous rectification diode with a closed gap, the external pin of the first frame is the cathode of the synchronous rectification diode, and the external pin of the second frame is the anode of the synchronous rectification diode. The lead-out end of the capacitor located at the open gap is the capacitor terminal. As shown in Figure 4, when the cathode voltage is greater than the anode, the built-in capacitor is charged to supply power to the control IC chip; when the control IC chip detects that the component terminal voltage is greater than the turn-on voltage Von, the MOSFET chip is turned on, and when the component terminal voltage is detected to be zero , turn off the MOSFET chip.

Example 4:

The two-piece synchronous rectification diode with a closed gap is shown in Figure 5 and Figure 6 in forward rectification and reverse rectification applications. In forward rectification applications, the AC input first passes through a bridge rectifier circuit, then filtered, pulse width modulated, and then transformed by a transformer. Regulated load. In the application of reverse rectification, the AC input first passes through the bridge rectifier circuit, then filtered, pulse width modulated, and then transformed by the transformer. Regulated load.

Of course, the above descriptions are only preferred embodiments of the present invention, and the present invention is not limited to the above-mentioned embodiments. It should be noted that any person skilled in the art can make all the Equivalent substitutions and obvious deformation forms all fall within the essential scope of this specification and should be protected by the utility model.

Claims (5)

1. The two-piece synchronous rectification diode with closed gap is characterized in that it comprises a first frame (1), a MOSFET chip (2), a control IC chip (3), a second frame (4), a built-in capacitor (5 ), the second frame (4) has two external pins, the second frame (4) is provided with a closed gap, the control IC chip (3) is fixed on the second frame (4), and the built-in capacitor (5 ) is connected to the second frame (4), and the internal terminal is located at the closed gap; The first frame (1) is provided with an external pin, and the MOSFET chip (2) is fixed on the first frame (1); The MOSFET chip (2), the control IC chip (3), and the built-in capacitor (5) are connected through bonding wires. 2. The two-piece synchronous rectification diode with closed gap according to claim 1, characterized in that, the built-in capacitor (5) is an MLCC capacitor. 3. The two-piece synchronous rectifier diode with a closed gap according to claim 1, characterized in that, the first frame (1) and the second frame (4) are copper alloy frames. 4. The two-piece synchronous rectifier diode with closed gap according to claim 1, characterized in that, the first frame (1), MOSFET chip (2), control IC chip (3), and the second frame (4) The built-in capacitor (5) is welded and molded by bonding wires and packaged in a plastic package to form an integral synchronous rectification diode. 5. The two-piece synchronous rectifier diode with closed gap according to claim 1, characterized in that, the external pin of the first frame (1) is the cathode of the synchronous rectifier diode, and the second frame (4 ) The external pin is the anode of the synchronous rectification diode.