Patent Application
20080002378
Switch mode power supplies are widely used in a variety of applications to convert Alternating Current (AC) mains power to one or more electrically isolated Direct Current (DC) outputs. The technology used for switch mode designs has improved substantially over the past decade allowing for smaller and more efficient designs. As designs footprints have shrunk and as power conversion efficiency has improved many new packaging options have become feasible. As a consequence, power supply customers are demanding an ever increasing array of packaging options.
Typical packaging options include, but are not limited to the following.
In addition to the basic packaging styles described above, there are many other options available. Most of these relate to different ways to remove heat, connect to or from the power supply, or reduce electromagnetic interference.
The unfortunate consequence of a wider array of options is difficulty in maintaining suitable stock in the distribution channels and increased production costs. A key consequence of the variety of packaging options means that there are often multiple versions of the power supply circuit reproduced on different printed circuit boards. The key difference between these boards are related to the mounting of the board in the various packages. While this will tend to optimize the design of each particular power supply and package combination, it greatly adds to the complexity of a broad product line. This adds cost and complexity since each printed circuit board must be designed, tested, and approved by the appropriate safety agencies. It also adds distribution costs since redundant parts must be used to fully stock the distribution channel.
The drawing submitted herewith is a photograph of a power conversion device frame package in accordance with and manifesting aspects of the invention in its currently preferred form.
This invention is for an improved packaging concept allowing standardized printed circuit boards to be re-used in a variety of packaging options. Rather then redesign the printed circuit board with different mounting characteristics for each packaging option, the invention utilizes a standardized printed circuit board and a snap-on plastic frame acting as an adapter to convert, combine and meet the mounting, interconnection, heat removal and electromagnetic characteristics of the overall power supply.
The invention focuses first on power supplies designed for desk top or wall mounted packages. These packages pose a significant design challenge since the plastic walls limit the removal of heat from the power supply. If a power supply can meet the thermal restrictions posed by a plastic case then it will typically perform even better as an open frame, semi-enclosed module or U-channel power supply.
Wall mount and desk top power supplies are typically designed for minimum size. A common mounting technique is to use edge card type connections between the power supply and the AC input connections. This is replicated for both input and output connections. A snap-on frame makes use of the same edge card design. Since other packaging techniques are generally less space constrained, the frame clips to the printed circuit board to provide mounting, interconnection, EMI protection and other features required by the end user of the power supply.
From a supply chain management point of view this increases flexibility of the product. A single printed circuit board can be packaged in many different ways. The printed circuit board can be manufactured in larger volumes, which lowers costs. Likewise, by standardizing the printed circuit board dimensions the frames can be used with several different power supply boards. This flexibility limits the inventory costs in the channel since it modularizes the product into components that can be stocked and easily assembled to meet demands of individual customers.
This patent application claims the benefit, under the applicable provisions of 35 USC 119 and 120, of the priority of U.S. provisional patent application Ser. No. 60/551,915, entitled “Frame Packaging System for Power Conversion Devices, filed 10 Mar. 2004, the disclosure of which is hereby incorporated by reference in its entirety, and is a continuation of U.S. utility application Ser. No. 11/075,539, filed 9 Mar. 2005, the priority of which is also claimed.
| Number | Date | Country | |
|---|---|---|---|
| 60551915 | Mar 2004 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | 11075539 | Mar 2005 | US |
| Child | 11820476 | Jun 2007 | US |
