I've been looking around on the web for a datasheet on an old 4 digit 7 segment display that has all 22 of its pins on one side (LTC-614A1P is the series number on the back of it) and I cannot find a single one! Does anyone have a place on the internet with it or have a pdf or something? This would really help me out a lot!
A lot of 7 segment displays are special modules and were never released for general sale. The good news however is that with a power supply and a 1K resistor it is easy to map out any pinout it may have.
Four digits of seven segments suggests 28 pins plus a common. Otherwise I would expect four commons to select the digit and seven segments, total of 11 pins.
Neither of these work with 22 pins.
As Grumpy has said, you can workout the pins with a power supply and R.
Firstly use a multimeter to check for any pins that are connected together. Then systematically put a gnd on one pin and move the R across all other pins and note any segments that light. Record the pins and polarity. Move the gnd and repeat.
Weedpharma
Hi
LTC, stand for Lite-On manufacturer
Try a search over google by "LTC lite one 7 segment 4 digit" as picture, you could get luck the find a similar one.
I use to test unknown models with my multimeter in diode mode. Getting a common pin, it start to light the segments one by one.
Hi,
Don't forget that not all pins may be used.
The multimeter on diode test and a pen and paper, will quickly sort out your pins.
Tom.... 
Thank you all for the help! I used my arduino to supply power and I tested all of the pins. I noticed that the LEDs looked really dim with a resistor, so I took it out. thankfully the display was very cheap so I didnt really care if a LED blew. Turns out there are internal resistors which is a very nice feature. I figured out all of the pins and the reason for the extra pins was because there are extra dots on the display. it's a common anode display, so you have to switch between digits fast enough for it to not be noticed. I also might make my own datasheet and put it on a website somewhere so people with my problem can use that.
TheProdigy22:
I noticed that the LEDs looked really dim with a resistor, so I took it out. thankfully the display was very cheap so I didnt really care if a LED blew. Turns out there are internal resistors which is a very nice feature.
Exactly, how did you come to that conclusion? I've never ever seen a display like that with integrated resistors, so i'm a bit interested to heat about yours.
// Per.
Hi,
Good you got it sorted, may I suggest if you are going to continue experimenting with electronics/arduino you get yourself a DMM.
Just a cheap one will do, just needs to measure volts/ohms/current (just to 10A is norma) /diode check.
Tom...
TomGeorge:
Hi,
Good you got it sorted, may I suggest if you are going to continue experimenting with electronics/arduino you get yourself a DMM.
Just a cheap one will do, just needs to measure volts/ohms/current (just to 10A is norma) /diode check.Tom...
Unfortunately the diode check functions on a lot of meters limits the test voltage to less than the forward voltage of many LEDs. I had a really good one that would display the value of the voltage (up to about 5V). The LED would simultaneously light dimly. But now that I'm using cheaper ones, I am finding that they are only good for 0.7V diode testing.
I recently found a LTC-614 display. This is a Lite-On 3.5 digit display, and looks like this: 1888:
This is similar to a clock display without the ":" in the middle and with an extra two dots on the right. I determined the following pinouts - looking at the front, starting with pin 1 on the left side. Segment A is on the top, the rest follow clockwise.
Pin - Segment
1 - not connected
2 - not connected
3 - not connected
4 - 2A, 3A, 4A
5 - 1B, 2B, 3B, 4B
6 - Common anode for first digit
7 - Common anode for second digit
8 - 1C, 2C, 3C, 4C
9 - 2D, 3D, 4D
10 - Common anode for third digit
11 - not connected
12 - not connected
13 - not connected
14 - not connected
15 - not connected
16 - Common anode for fourth (last) digit
17 - 2E, 3E, 4E
18 - 2G, 3G, 4G
19 - 2F, 3F, 4F
20 - upper dot (like a degrees symbol)
21 - lower dot (like a decimal point)
22 - Common anode for dots
- Happy Circuiting!