A DIY SN74HC595 Dot-Matrix Display

 A dot matrix display is very popular among novice electronics students or hobbyists. They are widely available today with a very low cost. Using a dot matrix module with an Arduino is very common since they are very low cost and rich of resources.

Finished PCB Testing with an Arduino Uno

When I was a student a dot matrix module were expensive and it's difficult to find locally. So I bought some dot matrix displays, SN74HC595 and transistor driver to interface to a micro-controller. 

Finished Hand-made PCBA

Finished Hand-made PCBA

Making this dot matrix display by hands is very busy. I had to etch, clean, drill holes and assembly all parts on the PCB. It took a whole day to complete. 

For more details about this PCB please see this post. 

A DIY SN74HC595 8-digit and 10-digit Serial 7-Segment Display

The SN74HC595 is a popular standard logic shift registers chip. I has been used for driving dot matrix display, LEDs, relays etc. Driving a multi-digit serial seven-segment display is very convenience since the multiplexing method could not drive any display that's exceed 10 digits. However using a shift registers chip to drive the display yields a high brightness. 

Arduino Testing

 

 

Finished PCB Assembly

 

If we have any individual-digit seven-segment display (any common anode or common cathode) we can put them together to make a serial display module manually. I have a dozen of the SN74HC595, common cathode seven-segment display, singled-sided copper clad board, passive components etc. So I want to make my own DIY display module. I have a Canon Laser printer with a good quality ink that can cover the circuit pattern well from acid penetration during etching. A toner-transfer method is suitable for this DIY single-sided PCB since the overall circuit is not complex. 

Copper Pattern Transferring to Copper Clad Board

I use the traditional Ferric Chloride acid etching yielded an acceptable quality with low cost. 

Finished PCB Etching and Drilling

Using a stand-drill with a machine-tool drill bit can easily drill all component pin holds of this FR-4 fiber glass PCB.

Digits Testing Using an Arduino Uno

We can control this serial display easily via an Arduino or a PIC microcontroller using their SPI interface. For more detail about this display see this post.