EP-4184568-B1 - HIGH-FREQUENCY PACKAGE

Inventors

• TANOBE, HIROMASA

Dates

Publication Date

20260513

Application Date

20200720

Claims (3)

1. A high frequency package comprising: a package main body (101) including a substrate (101a) made of an insulator; a differential coplanar line (102) formed on the substrate (101a); a first signal lead pin (106) arranged on a mounting surface of the package main body (101) and bent such that a first end of the first signal lead pin (106) is connected to a first signal line (103) of the differential coplanar line (102), and a second end of the first signal lead pin (106) is apart from the mounting surface; a second signal lead pin (107) arranged on the mounting surface of the package main body (101), bent such that a first end of the second signal lead pin (107) is connected to a second signal line (104) of the differential coplanar line (102), and a second end of the second signal lead pin (107) is apart from the mounting surface, and extending in the same direction as the first signal lead pin (106); and a ground lead pin (108) arranged on the mounting surface of the package main body (101), bent such that a first end of the ground lead pin (108) is connected to a ground line (105) of the differential coplanar line (102), and a second end of the ground lead pin (108) is apart from the mounting surface, and extending in the same direction as the first signal lead pin (106), characterized in that : a distance between the second end of the first signal lead pin (106) and the second end of the second signal lead pin (107) is different from a distance between the first end of the first signal lead pin (106) and the first end of the second signal lead pin (107), at the first end of the ground lead pin (108), a first embedded portion (118) is partially embedded in the substrate (101a) in a thickness direction, and in that : a portion of the first end of the ground lead pin (108) including the first embedded portion (118) is formed thicker than in other regions, or the portion of the first end of the ground lead pin (108) including the first embedded portion (118) is formed wider than in other regions, or at the first end of the first signal lead pin (106), a second embedded portion (116) is partially embedded in the substrate (101a) in the thickness direction.
2. The high frequency package according to claim 1, wherein a distal end of the second end of the ground lead pin (108), a distal end of the second end of the first signal lead pin (106), and a distal end of the second end of the second signal lead pin (107) are arranged on the same line, and the ground lead pin (108) is longer than the first signal lead pin (106) and the second signal lead pin (107).
3. The high frequency package according to any one of claims 1 or 2, wherein each of the first ends of the first signal lead pin (106) and the second signal lead pin (107) comprises a narrow portion (116a, 117) formed narrower than in other regions, and a distance to the ground lead pin (108) adjacent to the narrow portions of the first signal lead pin (106) and the second signal lead pin (107) is wider than in other regions.

Description

Technical Field The present invention relates to a high frequency package including a differential coplanar line. Background Art In a device configured to process a high-speed differential signal, including digital coherent optical transmission, a high frequency signal device package including a differential coplanar line in which two ground lines are arranged across two signal lines adjacent to each other is used. In the differential coplanar line, it is important to make an appropriate high frequency design for impedance matching and the like between the ground line and the signal line or between the two adjacent signal lines from a printed board to a semiconductor chip. In this high frequency design, a distance between wirings, a distance between lead pins connected to the wirings and used for mounting, and the shapes of the lead pins are very important parameters. Related Art Literature Patent Literature US 5,196,725 relates to high pin count and multi-layer wiring lead frames with the stated goal of having a short pitch, high density lead pattern and enhanced transmission characteristics for high-frequency signals.US 2019/0148316 A1 relates to high-frequency ceramic boards and high-frequency semiconductor element packages.Patent Literature 1: Japanese Patent No. 4934733 Non-Patent Literature Non-Patent Literature 1: Implementation Agreement for Integrated Dual Polarization Intradyne Coherent Receivers, IA # OIF-DPC-RX-01.2, November 14, 2013.Non-Patent Literature 2: Chang Fei Yee, "Key high-speed connector layout techniques", [searched July 10, 2020], (https://www.edn.com/key-high-speed-connector-layout-techniques/). Disclosure of Invention Problem to be Solved by the Invention However, standardization bodies such as "Optical Internetworking Forum" have decided the sizes and positions of lead pins to be solder-mounted, which should be satisfied by a high frequency signal device package holding a semiconductor chip and mounted on a printed board. It is therefore impossible to freely decide the distances and shapes of lead pins. As described in non-patent literature 1, the shapes of high frequency lead pins are defined (see Fig. 9), and a change of pitches between signal (+)/(-) leads necessary for improving the high frequency characteristic is not permitted. As described above, since the degree of freedom of the high frequency design in high-speed signal transmission is low, it is impossible to appropriately set electromagnetic coupling serving as a differential transmission path between two signal lines. For example, non-patent literature 1 shows an optical reception module 400 which includes a DC terminal 403 and an output terminal 404 and on which an optical circuit 401 configured to perform optical signal processing for optical signals input from two input ports 402a and 402b is mounted, as shown in Fig. 10. In this technique, details of the structure of a high frequency lead pin that affects the high frequency characteristic in the optical reception module including a plurality of high frequency lead pins are not disclosed. Also, in non-patent literature 2, the three-dimensional shape of lead pins is shown (see Fig. 11). It is assumed that all the pitch intervals between metal pads on a printed board and a distance between the lead pins are equal from the contact surface. Since the impedance becomes high in portions exposed to air, two signal lead pins are preferably brought as close as possible even from halfway. However, such a structure is not shown in detail and is not mentioned at all. The present invention has been made to solve the above-described problems, and has as its object to appropriately set electromagnetic coupling serving as a differential transmission path between two signal lines in a high frequency package including a differential coplanar line. Means of Solution to the Problem The invention is set out in the appended set of claims. Effect of the Invention As described above, according to the present invention, it is possible to appropriately set electromagnetic coupling serving as a differential transmission path between two signal lines because each lead pin is bent such that each lead pin, whose one end is arranged on the mounting surface of the package main body, has the other end apart from the mounting surface. Brief Description of Drawings It should be noted in the following that Figures 1-3 are not embodiments of the present invention, but are useful for its understanding. Only the embodiments of Figures 4-7 represent embodiments of the present invention. Fig. 1A is a plan view showing the configuration of a high frequency package according to the first embodiment;Fig. 1B is a perspective view showing the configuration of a part of the high frequency package according to the first embodiment;Fig. 1C is a perspective view showing the configuration of a part of the high frequency package according to the first embodiment;Fig. 2 is a plan view showing the configuration of a