Which I2C IC would you recommend to drive a large number e.g. 72 common anode 7-segment LEDs? Example schematic would also be handy.
I'm currently thinking of using common cathode 3-digit 7-segment LEDs in blocks of two. Each pair driven by a single MAX7219, so that'll be 12 MAX7219's connected in series.
Is that a feasible proposition to run using an Arduino? Eventually I'll have a standalone ATmega CPU. Will I be able to successfully run from a 5V supply or would I need more power?
Is that a feasible proposition to run using an Arduino?
Yes.
Will I be able to successfully run from a 5V supply or would I need more power?
I don't understand. If you are using an external power supply anyway then just get one that can supply the required current.
Note this is not an I2C solution like you origional asked for.
Grumpy_Mike:
Yes.
I don't understand. If you are using an external power supply anyway then just get one that can supply the required current.Note this is not an I2C solution like you origional asked for.
Thank you. I'm still quite new to this.
I decided to go with MAX7219's as it's probably easier to control the LED's with those dedicated IC's
OK I would have suggested that solution when you first posted, but it was not an I2C chip.
The MAX6954 will handle 16 digits of 7 segment displays, but you might find that harder to drive, or more than twice the price.