Serial 7-segment LED display module (4 digits)
This serial LED display module allows you to interface a 4-digit 7-segment LED display with only three I/O pins of a microcontroller, and gives you full control of all digits and decimal points.
- based on MAX7219 display driver
- SPI interface (3 pins)
- operates at +5V supply
- individual control of all digits and decimal points
- display brightness control through software
- dimensions 1.95″ x 1.4″ (50mm x 36mm)
- 0.56″ LED display
Here’s an example that shows how to interface this display module with PIC microcontrollers.
Assembling the board
- printed circuit board (1)
- MAX7219 (1)
- 0.56″ four-digit seven segment LED display (1)
- 1N4148 diode (1)
- 18K resistor (1)
- 100nF capacitor (1)
- 5-pin straight male header
The following pictures describes the assembling procedure.
Revision 1 (12/15/2012)
The PCB has slightly been revised recently. Everything remains the same except there are two header connectors available now. One for interfacing the display with a microcontroller and other for cascading multiple displays. New PCB is shown below.
Revision 2 (2/20/2013)
This has been revised second time and the new board will have following features:
- High quality 0.40″ display (LTC-4727JS) with bright yellow light emitting diodes
- Four digits, decimal and colon segments
- Round PCB corners
Price: $11.50 for kit, and $14.50 for assembled board. The payment will be through Paypal. If you want the kit or the assembled board, email me first at admin (at) embedded-lab.com, and I will send you my Paypal information. Or you can also buy it directly on Tindie.