Question For The Electronics Buffs

[Wendelspanswick]

I have a badminton scoreboard that I made using an Arduino Uno, an Adafruit wireless transmitter/receiver and an Adafruit HT16K33 7 segment led driver.
This currently uses a multiplexed 1.2" 4 digit 7 segment display but I've bought some larger 2.3" 7 segment displays as replacements but the HT16K33 will only handle up to 5.5V whereas the new display needs 7.5V.
Can I just stick some 7407 non inverting hex buffers on the output to increase the driver voltage and is there a dual version of the 7407 that does more than 6 outputs as I need 11 outputs in total (7 segments + 4 commons).
The outputs on the HT16K33 are current limited to protect the LEDs, I guess I will have to add current limiting resistors to the 7407 chips.

 

[galooph]

You could always use a couple of ULN2803 darlington drivers, especially if your displays are common anode.

 

[Wendelspanswick]

You could always use a couple of ULN2803 darlington drivers, especially if your displays are common anode.

Common cathodes for the displays but thanks for the heads up on the chip as I do have some smaller common anode displays.

 

[john_nz]

If anyone is still interested in knowing how to drive the large led displays with a HT16K33, I have just completed a clock with those displays and the HT16K33.
I am happy to draw up the interface, just let me know.

 

[Wendelspanswick]

If anyone is still interested in knowing how to drive the large led displays with a HT16K33, I have just completed a clock with those displays and the HT16K33.
I am happy to draw up the interface, just let me know.

Hi John, thanks for posting.
The badminton scoreboard has been pushed to the back at the moment as we are having a summer for once in the UK.
But I would be interested in seeing how you have interfaced the large digit LED's to the HT16K33 to give me some pointers for when I get round to sorting out mine.
Cheers.

 

[john_nz]

Hi, Here is the schematic for the display driver, let me know if you have any questions.
(Small typo in schematic, I meant to say 2.3" displays not 5.2" )