A Review of the Bellin Dynamic Systems Inc. Snap-Apart Surface Mount PCB Prototyping Systems

Ryan Shuttleworth, Member Society for Amateur Scientists

Last November I read an article in The Citizen Scientist entitled "The Quest for a 21st Century Prototyping Board " (18 November 2005). This article described an electronics prototyping issue with which I am all-too-familiar, the need for a fast, low cost and convenient way to prototype electronics circuits composed of modern surface mount device (SMD) components.

From the perspective of an electronics designer, I greatly appreciate the SMD revolution, for it has given me the ability to concentrate a great deal of functionality into a very small space. However, from the perspective of a hobbyist and assembler of these small circuits, I have found it increasingly difficult to assemble functional prototypes of designs that incorporate these ever-shrinking packages. I have examined numerous SMD prototyping systems over the years and so far only one system has won my loyalty: The “Snap-Apart” system of Bellin Dynamic Systems Inc.

The “Snap-Apart” system consists of 127 mm x 178 mm (5 in x 7 in) sheets of 32 mil FR4 printed circuit boards (PCBs). Each sheet is scored into numerous small circuits designed to conveniently support the vast majority of commercially available SMD packages. Bellin Dynamic Systems offers numerous assortments of these small circuits, and I encourage the reader to visit the Bellin web site to find a collection which best suits his or her needs.

Figure 1 shows a small section of a larger 127 mm x 178 mm “Snap-Apart” board. As you can see, each of the small PBC sections consists of the SMD footprint and convenient through-holes into which you can insert a standard 0.1 in SIP header. The insertion of the header allows the user to insert the circuit into a typical prototyping breadboard as shown in Fig. 4. SIP headers are included with each purchase of a “Snap-Apart” board.

Figure 1. A small section of one of the many assortments of “Snap-Apart” SMD prototyping systems.

Not all of the available “Snap-Apart” boards consist of a single footprint. Many of the boards are double sided with a different footprint on each side. Other boards include support circuitry footprints that allow the user to add components such as SMD bypass capacitors and regulators. Figure 2 shows a close-up of one such PCB along with a couple of convenient boards for MSOP-8 and SOT-23-6 support.

Figure 2. A close-up of a multi-function PCB and two convenient PCBs that support SOT-23-6 and MSOP-8 packages.

Figure 3 is a close-up of some assembled boards I have used in my prototyping adventures. Clockwise from the top left you can see a precision, low distortion 60 kHz oscillator, a PIC with reset and supply bypass circuitry, a mounted RMS to DC IC and a small 12-bit SMD DAC IC.

Figure 3. An assortment of assembled “Snap-Apart” boards.

Figure 4 shows an assembled breadboard prototype consisting of two half-H-bridge ICs, an SOT-23-3 MOSFET and support connections. You can see that the “Snap-Apart” PCBs are well suited to this style of prototyping.

Figure 4. “Snap-Apart” PCBs installed on a breadboard.

As I mentioned above, the “Snap-Apart” prototyping system is by far the best I have ever used. It has saved me an enormous amount of time, money and frustration, and I strongly encourage electronics professionals and hobbyists to examine the system for themselves. “Snap-Apart” boards are available directly from Bellin or from their distributor Mouser. Kits consisting of large assortments of boards are also available at bulk-discounted prices.