What LED 7 segment displays to buy

[kennydow241]

Hi,
I am looking for some common anode LED seven segment displays.

Ideally they should be between 1" and 2". I don't care what colour they are but they do have to be bright.

I already have the driver for them which is a Maxim ICM 7225 with a built in 9mA current limiter.

I have found that most of the displays that size need more than 9mA.





Thanks for any help

Kenny

 

[bonxer]

The brightness of an LED depends on the amount of current going through it, and the angle you are viewing it at (which doesnt much matter for 7-segs). By limiting your current to 9mA, you are limiting the brightness that the LEDs are capable of reaching.

Go to https://www.jameco.com and search for item 97199. It's a 2.24" 7-segment that has 12 to 21 mcd illumination. Perhaps someone else knows of a brighter one in this small size?

 

[kennydow241]

Thanks for the help.

If only there was a chip out there that could do all the things of the Maxim ICM 7225 but with a slightly higher limit for the current available to the LEDs.

On my travels I did find the SA15-11SRWA from Knightbright on RS components (rswww.com). It is super bright red. On the Data sheet most of the light level values are given with a current of 10mA. Hopefully these will be bright enough for me.

Thanks again

Kenny

 

[captainkirksdog]

Why not just use some pass-transistors? If your Maxim chip has the output MUXed, all you need is 7-8 small-signal types like the 2N3094 or 2N3906 (depending on your particular arrangement), a current-limit resistor for each display, and power for the LED's (can be same). Done.