# Looking for spec sheet National NSM4507

#### bbiandov

Joined Nov 24, 2007
31
Hi

Looking for spec sheet National NSM 4507 smart 2-digit 7 segment LED board. It just has too many pins for power data and clock?

The PDF that is floating around the Internet is only a summary sheet and does NOT show PINs etc

If anyone has the other pages please let me know

Thanks

#### Dave

Joined Nov 17, 2003
6,960
I've not come across a datasheet for the NSM 4507 at the usual sources. Might I suggest you contact National directly (contact details on National's website) to request the datasheet. They should have a copy, even if it is in the archives, which they could (e-)mail to you.

Dave

#### RiJoRI

Joined Aug 15, 2007
536
Looking for spec sheet National NSM 4507 smart 2-digit 7 segment LED board. It just has too many pins for power data and clock?
You are right about two many pins for serial communication. I'll bet the seven pins at the top of the picture are for telling the board which LEDs are to be lit. Usually a-f are used, going clockwise with a as the topmost LED, d as the bottommost, and f as the middle bar. There will also be a Common pin (or maybe two) for connection to either ground or V+, and I'd again bet that there is some type of address pin to select which 7-segment group you are addressing.

'Speriment time!

--Rich

#### bbiandov

Joined Nov 24, 2007
31
well yes and no. Those are made to be cascated so I know exactly how to get 7 pins but I just dont know which is which. Those boards use simple bit shifting and are made to cascade to almost any lenght of digits. They use shift register internally and NO refresh as today's design. That is why those old LED instruments never show the typical blanking when you film them with cam corder... No refresh, they are solid ON direct drive.

1 and 2 = power and GND
3 and 4 = data and clock IN
5 and 6 = data and clock OUT
7 = PWM blank-out used as intensity control of the LED

So here I have 7 but I do need to know which is which???

#### bbiandov

Joined Nov 24, 2007
31
National support is being an *ss. Their links and info all point to public domain PDFs. I could have found that stuff myself (which I did) why contact them if public domain was providing sufficient info... LOL

#### grsham

Joined Feb 25, 2009
2
Is it worth $8 to get the data - assuming no one has the book and will the pages for you? Search amazon dot com for "new data update 5 national semiconductor" That book is supposed to have the NSM4507 data. As of the time of this posting it is available for as low as$8 delivered.

I have access to the 1979 Optoelectronics Data Book which contains the NSM4000A specifications but that one is a 4 digit device with 9 pins.

The 1981 Optoelectronics Data Book should have the detailed specs also.

#### poli512

Joined Mar 8, 2009
1
Hi "grsham"! Do u still have the spec sheet for the nsm4000a because i searched a lot but i didn't find them anywhere ? Thanx!!

#### bbiandov

Joined Nov 24, 2007
31
I would gladly pay the \$8 bucks but how do I know that what Amazon is advertising as the data book is actually the data book? I mean it is extremely unlikely that they would find it feasible to sell anything like that these days so my guess is that the description is just in error.

Any way you can post your 4000 series, it might help derive some info for the other parts?

#### grsham

Joined Feb 25, 2009
2
Amazon does not directly sell all books, but is a marketplace for used book sellers to do so. At least one of the sellers I saw at the time of my original posting claimed to have update 5 and update 6. I believe the correct one is update 5. Of course the 1981 Optoelectronics Data Book would be the preferred source but I've not found that one.

I've attached a 4-page pdf of the NSM4000A specifications. I don't have a lot of confidence that it is sufficiently similar to the NSM4507, but I hope it helps and you will post followup experience.

Second try to upload the pdf. First attempt appeared to fail.

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#### AlbertHall

Joined Jun 4, 2014
8,187
Looking for spec sheet National NSM 4507 smart 2-digit 7 segment LED board.
I have three of these displays. Did you manage to work out the connections?