[SOLVED] How to quickly test a 7 segment 4 digit ?

Hi, I got two 7 segment (scored from what looks like a frequency counter circuit ) - 4 digit display like the one in the below link.
https://dlnmh9ip6v2uc.cloudfront.net/images/products/9/4/8/2/09482-04.jpg
It looks like 8.8.8.8 Model No: LTC5723G-01

Is there any quick way to test whether it works or not? I guess that I can do a small circuit to test if needed, but may not be able to do complex circuits as I just started to learn Electronics. Thanks in advance !!

no need to make circuit and all. take a 5v dc supply and give a small resister of 1 k aprox. and connect the ground to last pin ;
or try its opposite. In that display there will be a common pin which is for ground or vcc(5v).
ie: that pin will stay as common. mostly this pin will be down left. try it. do the opposite also.

getavinks can you be more specific you mean the Vcc pin or the Gnd pin

and what will be the response of the displays

In this type of displays (multiplexed) each of the segments and decimal point of every digit are connected together and each digit has a common pin. This common pin could be the anodes or the cathodes of each led.
This is a very short explanation see a sample datasheet to view it more clearly:

You can test as getavinks said or a simpler way is to use a multimeter in the diode check.
In either case you will be able to test only one segment at a time. The multimeter will display a value as if you were testing a diode but with more Vf. And it will lit the segment very dimly but it is enough to see if it works. Repeat for every led in the display. You will be able to identify the connections by comparing with the sample datasheet as you turn each led on.

getavinks@gmail.com said:

no need to make circuit and all. take a 5v dc supply and give a small resister of 1 k aprox. and connect the ground to last pin ;
or try its opposite. In that display there will be a common pin which is for ground or vcc(5v).
ie: that pin will stay as common. mostly this pin will be down left. try it. do the opposite also.

Click to expand...

albert22 said:

In this type of displays (multiplexed) each of the segments and decimal point of every digit are connected together and each digit has a common pin. This common pin could be the anodes or the cathodes of each led.
This is a very short explanation see a sample datasheet to view it more clearly:

You can test as getavinks said or a simpler way is to use a multimeter in the diode check.
In either case you will be able to test only one segment at a time. The multimeter will display a value as if you were testing a diode but with more Vf. And it will lit the segment very dimly but it is enough to see if it works. Repeat for every led in the display. You will be able to identify the connections by comparing with the sample datasheet as you turn each led on.

Click to expand...

Getavinks & Albert22.. Thank You guys!! We can test as getavinks said by referring the pdf sheet given by Albert22. Here is the summary of what they suggested ( will help novice like me :grin: )

There will be 12 pins in a 7 segment * 4 digit display. In which pin 6 controls the 4th digit, pin 8 controls digit 3, pin 9 controls digit 2 and pin 12 controls digit 1.
Each digit is made of 7 LEDs each responsible for one LED. The LED at the top of the digit is A. In clockwise, other LEDs numbered upto G; ie the central horizontal line is G. Heres the pin mapping: pin 1->E, 2->D, 3->dot, 4->C, 5->G, 7->B, 10->F & 11->A
I am unable to test all the LEDs in a digit togather but each LED in a digit can be tested at a time. Lets see how to test Digit 4th G LED. Connect a 5v input with 1k resistor, connect the ground to pin number 6 ( responsible for the 4th digit ) and positive lead to pin 5. If the LED should working fine, you will see the LED G in digit 4 should glow. Likewise you can test all the digits and LEDs.

Anyone please suggest a way ( if it exists ) to make all the LEDs of a digit or all the digits to glow together through a simple test?

To test a complete digit. connect one resistor to each segment (7 resistors) connect all the resistors to +5 and the common cathode of the digit to GND.
The polarity should be reversed if the display is common anode. You can check this with the multimeter before doing this test. Take care of polarity reverse because in the sample datasheet the max reverse voltage is 3V. You may want to use a power supply 3v or or less just to be sure.
In this way you can turn on the segments you choose.
If you connect more than a digit common, the leds gets connected in parallel and probably will lit only one of the paralleled set.
Follow the datasheet and dont be afraid to experiment. The resistors will protect against too much current and the 3v power supply against reverse.

albert22 said:

To test a complete digit. connect one resistor to each segment (7 resistors) connect all the resistors to +5 and the common cathode of the digit to GND.
The polarity should be reversed if the display is common anode. You can check this with the multimeter before doing this test. Take care of polarity reverse because in the sample datasheet the max reverse voltage is 3V. You may want to use a power supply 3v or or less just to be sure.
In this way you can turn on the segments you choose.
If you connect more than a digit common, the leds gets connected in parallel and probably will lit only one of the paralleled set.
Follow the datasheet and dont be afraid to experiment. The resistors will protect against too much current and the 3v power supply against reverse.

Click to expand...

Thank you!