# How to Check 7 Segment Display With a Multimeter

#### ByDevilal

Apr 26, 2022

Seven segment displays are the output display device that provides a way to display information in the form of an image or text or decimal numbers. It consists of seven segments of light-emitting diodes (LED s) which are assembled like numerical 8. Since seven segment displays can not form an alphabet like X and Z, so it can not be used for the alphabet and it can be used only for displaying decimal numerical magnitudes. However, seven-segment displays can form alphabets A, B, C, D, E, and F, so they can also use for representing hexadecimal digits. The Working of Seven Segment Displays is explained below.

## Checking 7-Segment Display with Multimeter

### Testing individual segments of a 7 Segment display:

seven-segment displays will have a CC mark for the common cathode and a CA mark for the common anode.

The above figure shows both the variants of 7 segment displays i.e the common anode and common cathode.

### Steps involved in testing:

• Hold the display in your hand and identify pin 1.
• Now take the multimeter (assuming a red lead for positive and a black lead for negative) and Keep the multimeter in diode mode shown in the below picture.
• Put your multimeter red lead on pin 3 or 8 as shown in the figure.
• Now put your meter’s black lead on any other pin such as 1,2,3,4 or 5 as shown in the figure.
• If any of the display’s segments glow then the display is a common anode.
• Connect your meter’s black lead to pin 3 or pin 8.
• Now put the red lead of the multimeter on another remaining pin as shown in the figure.  If any of the segments glow then the display is a common cathode, as in a common cathode the negative pin is common and the rest are connected to a positive supply.
•  Check all segments of both common cathode and anode to ensure the display is working properly.
•   If no segment glows, this 7 segment is faulty.