No, I am not talking about jumping into the wilderness, visiting an old European city or using Google Maps to get to your destination. Actually, the correct analogy would be more like going to a giant mall and having a map showing where the different shops, staircases and lifts interconnect the different floors. What I am referring to is a very powerful and simple tool which is normally overlooked by more analytical and less visual people, I am talking about our device map or more commonly known as a circuit block diagram.
A block diagram is an essential and required work product to have through the whole development cycle of the device. At the initial development stage serves as a foundation to visualize how the components interconnect each other and aid you in the design of the circuit. It is a bit like writing a book, first you write down the topics and subtopics so you can after-wards focus on researching and writing each topic. With a block diagram you can have a similar approach; by dividing the circuit into sections, one can research separate parts of the circuits without losing track of where they are positioned in the rest of the system. Take the Mini Electronic Congas block diagram as an example:
Simple enough, but it serves its purpose. You can see how all the circuit interacts and you can easily associate symbols to work on the circuit. One afternoon you look how to do the buffer amplifier circuit for the piezoelectric sensor interface and the next morning you are looking for a battery charger IC. It is also very useful when you have to explain your circuit to someone else and the person needs to be brought into context, simplifying other tasks such as the Worst Case Analysis by having a general overview of the system.
After the circuit diagram design phase, the block diagram can also be useful to design the PCB, as you can initially draft your PCB idea using the same blocks from the block diagram:
There are many different types of block diagrams to represent a device:
- System block diagram: shows how the device interacts with other external devices, environment and users
- Wiring block diagram: focuses on the wire labels, positions and connector pinout between one PCB and the other. This is very useful for system engineers, wire designers and factory assembly people
- Circuit block diagram: pseudo circuit that shows the main electronics of the board and how they interconnect
- Input/Output block diagram: functional diagram that shows the functions going in and out of the circuit without entering into the circuit detail
Depending on the situation, you will need to choose one or what is more common, a mix of 2. Here is an example of a mix of a system with an input/out diagram for a wind energy battery charge controller:
So, how do I draft a block diagram of my product idea?
Obviously, this is not an exact science as calculating the current through a resistor with a given voltage, so it depends much on the designer. However, I find the following method very useful:
In this article, I have explained the importance of a block diagram during the development stages and also have given some tips on how to draft your own. Hopefully, you realize the importance of the circuit block diagram and how having a “map” can actually help you to develop your product.
Have you made a block diagram before? Do you have a different method? Share your thoughts in the comments section below.
Do you want to learn how to quickly design your circuit block diagram? Enroll on the Draft your Circuit Block Diagram Micro Course!