7 Segment LED Display Single Digit

There seem to be different approaches on forums etc. as to how many resistors are needed for a 7 Segment LED Display Single Digit. Those who suggest 8 resistors for a 1 digit 7 segment display do so because the "brightness" of each LED is constant regardless of the number of LEDs displaying the digit.
Others suggest that one resistor connected to the common cathode (or common anode as appropriate) is sufficient to ensure that the current does not exceed 40 mA.

With a 220 ohm resistor connected to the common cathode, the product of the current and voltage across the LEDs with 1 to 7 LEDs HIGH on a 1 digit 7 segment display is measured to estimate the power used by the LEDs. As expected, the current drops from 12mA to 2mA as the number of HIGH LEDs increases, and the power is estimated to be relatively constant at 22 to 25mW.

We can customize products according to customer's requirements on the special matrix height, dot size, and internal circuit and outline dimension.

Size, and internal circuit and outline dimension.

Hot Tags: 7 segment led display single digit, China 7 segment led display single digit manufacturers, factory, Lead Frame Dfn, Lead Frame, One Digit 7 Segment Display, 16 Segment Alphanumeric LED Display, Steel Speaker Grille, Copper Mesh Filter