CN218274586U - Three-chip synchronous rectification package structure with built-in capacitor support - Google Patents

Abstract

The utility model discloses a three-chip synchronous rectification package structure with built-in capacitor support, which includes a lead frame, and the lead frame includes: a first base island, which is installed on one side of the frame body through a first pin; a second base island, It is installed on the other side of the frame body through the second pin; the third base island is installed on the other side of the frame body through the third pin; there is a built-in capacitor between the second base island and the third base island. The utility model adds a third pin, the end of the third pin is provided with a third base island, and there is a certain distance between the first base island, the second base island and the third base island, and the second base island The island is flush with the upper wall of the third base island. By adopting the form of three base islands, the overall size can be reduced, the production efficiency can be improved, and the built-in capacitor can be effectively supported to ensure the stability of the built-in capacitor support.

Description

Three-chip synchronous rectification package structure with built-in capacitor support

technical field

The utility model relates to the technical field of integrated circuit packaging, in particular to a three-chip synchronous rectification packaging structure with built-in capacitor support.

Background technique

The synchronous rectification method is composed of control IC, power MOSFET and its auxiliary circuits, so as to realize the new technology of low loss rectification.

Chinese patent CN208336221U discloses a two-piece synchronous rectifier diode with an open gap. There are two external pins through the second frame. The second frame is provided with an open gap. The control IC chip is fixed on the second frame. The external terminal of the capacitor is connected to the second frame, and the internal terminal is located at the open gap; the first frame has an external pin, and the MOSFET chip is fixed on the first frame; in simple terms, by using a two-piece package Form, customize two frames with base islands, install the control IC chip and power MOSFET chip respectively, and then realize the connection of the circuit by bonding;

However, using the above-mentioned bonding method, since two frames need to be customized, the cost is high, and the overall size will be too large, and the two are on different frames, and different frames need to be fixed, and then installed separately , bonding, plastic sealing, sheet cutting and electrical inspection and other processes, and then complete the overall production process;

In addition, in the form of two frames, it is generally necessary to open a gap on one frame to accommodate the internal terminal of the built-in capacitor, so as to prevent the internal terminal of the built-in capacitor and the external terminal of the built-in capacitor from being electrically connected to the same frame, causing short circuit.

Utility model content

The purpose of this utility model is to solve the problem in the prior art that two frames need to be customized, the cost is high, and the overall size is too large, and a three-chip synchronous rectification package structure with built-in capacitor support is proposed.

Three-chip synchronous rectification package structure with built-in capacitor support, including lead frame, lead frame includes:

The first base island is installed on one side of the frame body through the first pin;

A second base island, mounted on the other side of the frame body via a second pin;

The third base island, installed on the other side of the frame body through the third pin;

A built-in capacitor is arranged between the second base island and the third base island.

As a further solution of the present invention: the second base island and the third base island are on the same level.

As a further solution of the present invention: the first base island and the second base island are not on the same level.

As a further solution of the present invention: the height of the top surface of the first base island is lower than the heights of the top surfaces of the second base island and the third base island.

As a further solution of the present invention: gaps are provided between the first base island, the second base island and the third base island.

As a further solution of the present invention: a first gap is set between the first base island and the second base island, and a second gap is set between the second base island and the third base island.

As a further solution of the present invention: multiple first pins and second pins are provided at equal intervals, and one third pin is provided.

As a further solution of the present invention: a MOSFET chip is arranged on the first base island, an IC chip is arranged on the second base island, and the MOSFET chip, the IC chip, and the built-in capacitor are connected by bonding wires.

As a further solution of the utility model: the external terminal of the built-in capacitor is installed on the second base island, and the internal terminal of the built-in capacitor is installed on the upper part of the third base island.

The beneficial effects of the utility model:

The utility model adds a third pin, the end of the third pin is provided with a third base island, and there is a certain distance between the first base island, the second base island and the third base island, and the second The base island and the upper wall of the third base island are flush. By adopting the form of three base islands, the overall size can be reduced, the production efficiency can be improved, and the built-in capacitor can be effectively supported to ensure the stability of the support of the built-in capacitor.

Description of drawings

Below in conjunction with accompanying drawing, the utility model is further described.

Fig. 1 is the structural representation of the utility model;

Fig. 2 is the structural representation of the utility model plastic package;

Fig. 3 is the control schematic diagram of the utility model;

Fig. 4 is the forward rectification circuit diagram of the utility model;

Fig. 5 is a reverse rectification circuit diagram of the utility model.

In the figure: 1. Frame main body; 2. First pin; 3. Second pin; 4. First base island; 5. Second base island; 6. Gap; 7. MOSFET chip; 8. Built-in capacitor; 9. IC chip; 10. plastic package; 11. third pin; 12. third base island; 13. second gap.

detailed description

The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. example. Based on the embodiments of the present utility model, all other embodiments obtained by persons of ordinary skill in the art without creative efforts belong to the scope of protection of the present utility model.

Example 1

Please refer to Figure 1-2, the utility model is a three-chip synchronous rectification package structure with built-in capacitor support, including a lead frame, which includes a frame body 1, a first pin 2, a second pin 3, The first base island 4, the second base island 5, the third pin 11, and the third base island 12;

The inner wall of the frame main body 1 is provided with first pins 2, second pins 3 and third pins 11, the first pins 2 and the second pins 3 are provided with a plurality of equidistant respectively, and the plurality of first pins The end of the foot 2 away from the frame body 1 is connected to the first base island 4, and the end of the plurality of second pins 3 away from the frame body 1 is connected to the second base island 4, and one third pin 11 is provided, and the third pin 11 The end away from the frame body 1 is connected to the third base island 12;

Wherein, the second base island 5 and the third base island 12 are on the same horizontal plane, and the second base island 5 and the third base island 12 are provided with a second gap 13;

The first base island 4 is not on the same level as the second base island 5 and the third base island 12, and has a height difference, and the projection of the first base island 4 on the horizontal plane and the projection of the second base island 5 on the horizontal plane are provided with first gap 6;

The height of the horizontal plane of the first base island 4 is lower than the height of the horizontal planes of the second base island 5 and the third base island 12; the lead frame is integrally formed and made of copper material.

Example 2

Based on the above-mentioned embodiment 1, the three-chip synchronous rectification package structure with built-in capacitor support is manufactured using the above-mentioned lead frame, and the steps are as follows:

Fix the MOSFET chip 7 on the top of the first base island 4; install the IC chip 9 on the top of the second base island 5, and install the two ends of the built-in capacitor 8 on the second base island 5 and the third base island 12 respectively The upper part, and the external terminal of the built-in capacitor 8 is installed on the second base island 5, and the internal terminal of the built-in capacitor 8 is installed on the top of the third base island 12;

Since the two ends of the built-in content 8 are supported by the second base island 5 and the third base island 12, the installation of the built-in capacitor 8 is more convenient and the installation is more firm;

The MOSFET chip 7, the IC chip 9, and the built-in capacitor 8 are connected through bonding wires, and the bonding wires are copper wires, gold wires, rake gold wires, etc.;

After the bonding is completed, plastic sealing is carried out, and the above-mentioned components are sewn inside the molding compound. The parts of the first pin 4 and the second pin 5 are not sealed in the molding compound, and the plastic sealing body 10 is formed after the molding compound is cooled;

Singling: After cleaning and tinning, cut off from the first pin 4 and the second pin 5 to form a single plastic package 10, which is a three-chip synchronous rectifier with built-in capacitor support package structure;

Then after visual inspection and electrical testing, it can be packaged and put into storage.

Example 3

Based on the above-mentioned embodiment 2, please refer to Fig. 3, the first pin 2 is the cathode of the synchronous rectification, and the second pin 3 is the anode of the synchronous rectification. When the cathode voltage is applied to the anode, the built-in capacitor 8 charges the IC chip 9 power supply; when the IC chip 9 detects that the component terminal voltage is greater than the turn-on voltage Von, the MOSFET chip 7 is turned on, and when it is detected that the component terminal voltage tends to zero, the MOSFET chip is turned off.

In specific applications, synchronous rectification is used in forward rectification and reverse rectification applications as shown in Figure 4 and Figure 5; in forward rectification applications, the AC input is first passed through a bridge rectifier circuit, and then filtered, pulse width modulated, by The transformer transforms the voltage, and the high-voltage end of the transformer is connected to the anode of the two-piece synchronous rectification diode with a closed gap, and then connected to the load through voltage stabilization. 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.

The working principle of the utility model: the utility model is provided with the third base island 12 by adding the third pin 11, the end of the third pin 11, the first base island 4, the second base island 5 and the third base island 12 There is a certain distance between the two base islands, and the upper walls of the second base island 5 and the third base island 12 are in a flush state. By adopting the form of three base islands, the overall size can be reduced, the production efficiency can be improved, and Realize effective support for the built-in capacitor 8, and ensure the stability of the support of the built-in capacitor 8.

An embodiment of the present utility model has been described in detail above, but the content described is only a preferred embodiment of the present utility model, and cannot be considered as limiting the implementation scope of the present utility model. All equal changes and improvements made according to the application scope of the utility model should still belong to the scope covered by the patent of the utility model.

Claims (9)

1. A three-chip synchronous rectification package structure with built-in capacitor support, including a lead frame, is characterized in that the lead frame includes: The first base island (4) is installed on one side of the frame body (1) through the first pin (2); The second base island (5) is installed on the other side of the frame body (1) through the second pin (3); The third base island (12) is installed on the other side of the frame main body (1) through the third pin (11); The second base island (5) and the third base island (12) are carriers of the built-in capacitor (8). 2. The three-chip synchronous rectification package structure with built-in capacitor support according to claim 1, characterized in that the second base island (5) and the third base island (12) are on the same level. 3. The three-chip synchronous rectification package structure with built-in capacitor support according to claim 2, characterized in that the first base island (4) and the second base island (5) are not on the same level. 4. The three-chip synchronous rectification package structure with built-in capacitor support according to claim 1, characterized in that the height of the top surface of the first base island (4) is lower than the top surface of the second base island (5) and The height of the top surface of the third base island (12). 5. The three-chip synchronous rectification package structure with built-in capacitor support according to claim 1, characterized in that the first base island (4), the second base island (5) and the third base island (12) There is a gap between the two. 6. The three-chip synchronous rectification package structure with built-in capacitor support according to claim 5, characterized in that a first gap ( 6), a second gap (13) is set between the second base island (5) and the third base island (12). 7. The three-chip synchronous rectification package structure with built-in capacitor support according to claim 6, characterized in that there are multiple first pins (2) and second pins (3) at equal intervals, the first Three pins (11) are provided with one. 8. The three-chip synchronous rectification package structure with built-in capacitor support according to claim 1, characterized in that, the first base island (4) is provided with a MOSFET chip (7), and the second base island (5) An IC chip (9) is arranged on the top, and the MOSFET chip (7), the IC chip (9) and the built-in capacitor (8) are connected through bonding wires. 9. The three-chip synchronous rectification package structure with built-in capacitor support according to claim 8, characterized in that, the external terminal of the built-in capacitor (8) is installed on the second base island (5), and the built-in capacitor ( 8) The inner terminal is installed on the upper part of the third base island (12).

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