MAX7219C/D datasheet by Maxim Integrated Products

MAX7219C/D Frequently Asked Questions (FAQs)

• What is the maximum clock frequency for the MAX7219C/D?
  The maximum clock frequency for the MAX7219C/D is 10MHz. However, it's recommended to operate at a clock frequency of 4MHz or less to ensure reliable operation.
• How do I initialize the MAX7219C/D?
  To initialize the MAX7219C/D, you need to send a shutdown command (0x0C, 0x01) followed by a display-test command (0x0F, 0x01) and then a scan-limit command (0x0B, 0x07) to set the number of digits to be displayed. Finally, send a shutdown command (0x0C, 0x00) to turn on the display.
• What is the purpose of the No-op command (0x00, 0x00) in the MAX7219C/D?
  The No-op command (0x00, 0x00) is used to synchronize the data transfer between the microcontroller and the MAX7219C/D. It can be used to insert a delay between commands or to ensure that the previous command has been executed before sending a new command.
• How do I adjust the brightness of the display using the MAX7219C/D?
  The brightness of the display can be adjusted by sending a intensity-command (0x0A, 0x00 to 0x0A, 0x0F) to the MAX7219C/D. The intensity value ranges from 0 (minimum brightness) to 15 (maximum brightness).
• Can I use the MAX7219C/D to drive a 7-segment display with a decimal point?
  Yes, the MAX7219C/D can be used to drive a 7-segment display with a decimal point. The decimal point can be controlled by setting the corresponding segment pin (SEG_DP) high or low.