AVT934 A

To connect a multiplexed, 8-digit LED display to a microprocessor system, you need 16 control lines. This forces the use of uPs with a large number of I / O lines. An alternative method is to use an I / O expander.
The set is an 8-digit LED display controlled via the SPI interface. As a result, only three control lines are sufficient to connect it to the microcontroller. The described module can be combined into larger blocks by connecting them in series or in parallel.
The "heart" of the device is the MAX7219 chip. It contains a 16-bit shift register as well as control systems for LED displays with common cathode.

The device is particularly useful for users of microprocessor systems using LED displays

Selected parameters:

• number of displays (digits) LED - 8
• displays with common cathode
• module control via the SPI interface
• the possibility of cascading connection
• display control - multiplex
• option to adjust the brightness of light
• the possibility of switching into the shutdown mode
• display testing function
• power supply - 5 Vdc
• printed circuit board and documentation included
  A detailed description in EP 6/06