I'm setting something up where I'm using 7 segment LEDs for data output. I've tested some smaller red 7 segment and have worked out the Arduino code, the wiring between the Arduino, MAX7219 & the 7 segment, and it has worked fine.
For the final product, I want to use larger 2.25" tall 7 segment, but I've run into trouble. I'm 98% certain that the wiring is correct, as is the code, but the 7 segment is not illuminating at all. Here is the link to the larger LED (Jameco #97201): http://www.jameco.com/webapp/wcs/stores/servlet/ProductDisplay?langId=-1&storeId=10001&catalogId=10001&pa=97201&productId=97201&keyCode=PDF and the one I used for the testing (Jameco #17187): http://www.jameco.com/webapp/wcs/stores/servlet/ProductDisplay?search_type=jamecoall&catalogId=10001&freeText=17187&langId=-1&productId=17187&storeId=10001&ddkey=http:StoreCatalogDrillDownView
They are both Common Cathode, and seem to have very similar power needs. I have a 10k resistor on the MAX7219 ISET pin, and two capacitors, (100n & 10pF) , between the ground and power, which are both supplied by the Arduino.
Does anyone more able and aware than me happen to see something obvious I'm missing?