Carrier PCBs for breadboards - an introduction
Figure 1 – Generic carrier board with a 78HC08 SOC-14 device
I make a fair few PCBs (Printed Circuit Boards) in the workshop and purchase my PCB laminate in standard sizes and cut it down to size as needed. Unfortunately the off-cuts are often too small to be of any real use in most projects but they do have at least one use, as breadboard carrier boards. Most connectors, switches, some IC’s (and all SMDs), etc were never designed to fit the standard 0.1” pitch matrix of a plug in breadboard, so carrier boards are usually required if you want to use these components.
The concept is simple in its basic form. You make a PCB to accommodate the part or connector and extend its pins to fit a standard 0.1” matrix.
The carrier PCB holds the component in question, and the components pins are extended to protruding pins that plug into the breadboard.If you’re going to make these there’s a possible pitfall to be wary of; square pegs don’t fit in round holes!
The concept is simple in its basic form. You make a PCB to accommodate the part or connector and extend its pins to fit a standard 0.1” matrix.
The carrier PCB holds the component in question, and the components pins are extended to protruding pins that plug into the breadboard.If you’re going to make these there’s a possible pitfall to be wary of; square pegs don’t fit in round holes!
Figure 2 - Common types of bread-board and interconnect pins
The top part of the above picture shows two types of common bread-board. The board top left has round holes, the one top right has square holes. The lower part of the picture shows two of the more common types of pin connector are available.
The square pins are supplied in various length strips, are often gold plated, very strong and give good surface area contact when plugged into the breadboard. They are also fairly cheap (£ 0.18 / 36 pins) but they tend to be a snug fit and when used on carriers with a reasonable number of pins, and can be difficult to plug into the breadboard; they can be even harder to get out again.
The round pins are more expensive (£ 1.59 / 32 pins), don’t give as large a contact surface area as the square pins but are simpler to insert into, and remove from the breadboard. They aren’t as robust as the square ones either, and are easy to bend or snap if you’re not careful.
I’ve found more and more suppliers are selling the breadboards with the round holes which is annoying, as the square, cheaper pins won’t fit unless you force them in. The round pins will fit either board.
I should say that there are several types of breadboards with round holes. I've recently bought some of the slightly more expensive ones and these do seem to accept the square pins, though they are a little tight. It looks like the problem is a bigger issue with some of the cheaper breadboards. A sensible rule would be to try a board before you invest is several of them if your not sure, and always remember that your supplier may have changed their supplier so you should check before re-ordering boards.
Now some of these parts, especially the surface mount IC’s are quite expensive and tricky to solder. Once you’ve managed to create the carrier board and attach the part then build and debug your prototype you may not be all that excited about the prospect of having to remove the part from the carrier board, and then re-solder it into the completed gizmo.
Well, you may not have too. As long as you’ve got room in the finished item, you can just unplug the carrier from the breadboard and then plug it into its final resting place as there are socket strips that fit both of the above pins. Needless to say, the sockets for the square pins are cheaper and more robust than the turned-pin sockets but you can't interchange the types, so be warned.
Figure 1 shows a simple carrier board that has a single surface mount IC soldered, and is really nothing too clever. However, you can expand on the carrier board concept and use it for more complicated applications.
The square pins are supplied in various length strips, are often gold plated, very strong and give good surface area contact when plugged into the breadboard. They are also fairly cheap (£ 0.18 / 36 pins) but they tend to be a snug fit and when used on carriers with a reasonable number of pins, and can be difficult to plug into the breadboard; they can be even harder to get out again.
The round pins are more expensive (£ 1.59 / 32 pins), don’t give as large a contact surface area as the square pins but are simpler to insert into, and remove from the breadboard. They aren’t as robust as the square ones either, and are easy to bend or snap if you’re not careful.
I’ve found more and more suppliers are selling the breadboards with the round holes which is annoying, as the square, cheaper pins won’t fit unless you force them in. The round pins will fit either board.
I should say that there are several types of breadboards with round holes. I've recently bought some of the slightly more expensive ones and these do seem to accept the square pins, though they are a little tight. It looks like the problem is a bigger issue with some of the cheaper breadboards. A sensible rule would be to try a board before you invest is several of them if your not sure, and always remember that your supplier may have changed their supplier so you should check before re-ordering boards.
Now some of these parts, especially the surface mount IC’s are quite expensive and tricky to solder. Once you’ve managed to create the carrier board and attach the part then build and debug your prototype you may not be all that excited about the prospect of having to remove the part from the carrier board, and then re-solder it into the completed gizmo.
Well, you may not have too. As long as you’ve got room in the finished item, you can just unplug the carrier from the breadboard and then plug it into its final resting place as there are socket strips that fit both of the above pins. Needless to say, the sockets for the square pins are cheaper and more robust than the turned-pin sockets but you can't interchange the types, so be warned.
Figure 1 shows a simple carrier board that has a single surface mount IC soldered, and is really nothing too clever. However, you can expand on the carrier board concept and use it for more complicated applications.
A complete circuit on a board.
Figure 3 - 16F876 with ICSP, crystal and support components on one PCB
One thing that I found myself doing time and again was mounting a PIC, adding crystal and associated capacitors, power, decoupling caps and ICSP connector at the start of a new breadboard project, so I decided to construct a set of carrier boards to hold the bare minimum required to make a PIC run. What this means is that it takes only a few moments to plug in the carrier, hook up the power and the ICSP cable your off.
RS232 interface on a board
You can of course adopt this process to entire circuit building blocks.
Another offen used sub-module is a standard RS232 interface so once again, I created a simple plug-in carrier board with all the required support electronics.
Over the years I've created a large assortment of plug-in modules that carry switches, LEDs, connectors and small circuits and any other components that cannot be simply plugged-in on a standard bread-board.
Another offen used sub-module is a standard RS232 interface so once again, I created a simple plug-in carrier board with all the required support electronics.
Over the years I've created a large assortment of plug-in modules that carry switches, LEDs, connectors and small circuits and any other components that cannot be simply plugged-in on a standard bread-board.
Available Carrier Board Designs
As time allows I will provide construction details for the carrier boards I use. Check back often.
PIC Carrier Board
This board is suitable for the PIC18F26K20/22, PIC18F876 and any other 28-pin PIC that has a similar pin-out
I've recently updated the design so it's compatable with the standard PICKIT ICSP connection.
I've recently updated the design so it's compatable with the standard PICKIT ICSP connection.
