K8035 with Kingbright sa18-11ewa

Kits Timers and Clocks
1

Hello, I’ve just finished making the K8035 timer, it works perfectly but I want use some spare display I got, they are the kingbright sa18-11ewa, a 45mm 7 segment display with common anode.

I’ve already plugged in these displays but the brightness is very low, maybe because the k8035 pic works at 5v DC? Testing separately with 12V DC, the displays are very bright.

Is there a way to use and connect these displays with the k8035 timer? If positive, how should I do?

Thank you for answers and sorry for my bad english :slight_smile:

2

It is normal that the displays are very dim. The original displays feature 1 led per segment, while the ones you connect feature 3 leds in series.
3x 1.6 = 4.8V, which is very close to the 5V, so the current will be very low. Replacing R1…R7(150 ohm) by a 10 ohm resistor can help, however, keep in mind that connecting such a display to a 5V source is not an example of good engineering.