I have a circuit running at 5V logic throughout the board, and I decided to use this 7 segment display:
http://www.kingbrightusa.com/images/catalog/SPEC/sc10-11ewa.pdf
with this decoder
http://www.nxp.com/documents/data_sheet/HEF4543B.pdf
Good engineering would tell me to put a resistor at the input of each segment, but I am using 15 of these displays, and since I'm not going to use the decimal point, that would come out to 105 resistors!
I've considered multiplexing the displays, but 15 displays might cause flickering with the slowest micros, and dimming with the fastest.
I noticed the Maximum rating for the LED segment I've linked to is 5V, and the typical rating is 4V, does this mean I can run it without resistors if I'm using a regulated 5V supply?
Are there any other tricks I can use to cut down the amount of resistors I'll need (eg a BCD-7Segment decoder with built in current limiting)?
http://www.kingbrightusa.com/images/catalog/SPEC/sc10-11ewa.pdf
with this decoder
http://www.nxp.com/documents/data_sheet/HEF4543B.pdf
Good engineering would tell me to put a resistor at the input of each segment, but I am using 15 of these displays, and since I'm not going to use the decimal point, that would come out to 105 resistors!
I've considered multiplexing the displays, but 15 displays might cause flickering with the slowest micros, and dimming with the fastest.
I noticed the Maximum rating for the LED segment I've linked to is 5V, and the typical rating is 4V, does this mean I can run it without resistors if I'm using a regulated 5V supply?
Are there any other tricks I can use to cut down the amount of resistors I'll need (eg a BCD-7Segment decoder with built in current limiting)?
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