|Digital Source Digital Players and Recorders: CD , SACD , Tape, Memory Card, etc.|
Please consider donating to help us continue to serve you.
Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
|29th July 2014, 01:54 AM||#1|
Join Date: Jan 2012
NSM4202A LED Display Module Replacement for Philips / Sony CDM Transports
I have an old Krell MD-2 CD turntable, and (among other issues) several segments have gone out on the LED display. After looking around online, I found one person in France that had built a replacement, but details were kind of scarce, so tried to reverse engineer my display module based upon the tidbits of information that I was able to uncover.
After hooking it up to a scope, it appeared to use SPI (keep in mind that I'm not very smart), but I just got rubbish when I created a small Arduino program to read the data, so I traipsed through the available LED drivers on DigiKey, and came across the MM5450 as one of the very few chips that didn't require I2C. Upon reviewing the data stream again, it appeared to fit with what was required to drive this chip. Anyway, I did the best that I could to guess the pinout of my existing display board (it uses an unmarked glob to hold down the IC die), and was able to reconcile it with the MM5450 pinout, so I made up a board, bought some parts, and tried it out. It appears to be fully functional, so I thought that I would share it here so that others can create a replacement for themselves as necessary. I'm kind of hoping that since this hardware is over 25 years old (and apparently out of production for quite some time) that Philips won't mind too much the publishing of plans for a replacement...
Anyway, here goes with the information:
Feel free to use this information however you wish, so long as you don't make anyone pay for it. I don't care if you charge someone to assemble a board for them or something (it's none of my business), but the information should be kept in the open. I abhor GPL-like licensing, but I do expect you to not be a turd.
I am just a hobbyist (and a really unintelligent one at that), so I do not make any representation that information is accurate, safe, or suitable for any purpose, even a purpose that may be implied by the information. In other words, I did the best that I could, it worked for me, but it's not on me if you hurt yourself or start a fire or something.
I have the board shared at OSH Park (https://oshpark.com/shared_projects/P3nC9ISV) for convenience. I make nothing from this link or design (AFIAK), and I don't care from where you order your board.
Front of PCB:
Back of PCB:
Gerbers for PCB:
DipTrace Schematic and Board Files:
NSM4202A DipTrace Files.zip
|14th February 2017, 07:38 PM||#2|
Join Date: Aug 2014
I have created an NSM4002 / NSM4202 replacement
Regards Bram Jacobse
U1 - Micrel MM5450 (PLCC-44) LED Display Driver
DS1-DS4 - Kingbright ACSA03-41SGWA-F01 7-Segment Common-Anode LED Display (Green, other colors probably available)
R1 - 10kOhm (or higher) 1206 SMD Resistor (controls brightness)
C1 - 1000pF 1206 SMD Capacitor
C2 - 100nF 1206 SMD Capacitor
J1 - 0.1" header system of your choice
|13th August 2019, 04:48 PM||#3|
Join Date: Oct 2010
Location: West Germany near Münster
I've several old Philips gear in use. My "Daily Player", a CD-460, also had the common problem with missing digits on the 4202(A). Not a big issue, as long as something could be seen. But during the last year most of the segments were lost.
I've found this thread, but as my eyes for some circumstances cannot deal with SMD, I asked Bram if he'll be willing to put a complete display together for me . And he did!
Installation was easy, and now my old buddy not only plays music like a young fellow, it even looks like one . Exact this player was the first CDP my father owned back in the 80's, and little Ingo liked watching the rotating CD through the window.
Thanks a lot, Bram, for sharing your work on Diyaudio and again a big thank you for the kind service!
(BTW: Complete reworked with NOS-conversion, but even better in combination with the Parasound D/A converter 1100HD.)
Last edited by Shoemaker; 13th August 2019 at 04:50 PM.
|13th August 2019, 05:22 PM||#4|
That is fantastic, really nice work those original display modules were a problem from the very beginning.
Installing and using LTspice IV. From beginner to advanced.
|Thread||Thread Starter||Forum||Replies||Last Post|
|anyone know a source for a NSM4202A LED board||gto127||Parts||6||4th October 2014 11:35 AM|
|Where can I get a replacement laser (CDM-0) for a Philips CD100||drjarmin||Digital Source||5||12th August 2013 12:56 AM|
|Philips CD950 display replacement||Superhill||Digital Source||2||1st July 2013 05:40 PM|
|WANTED: Replacement CD-PRO2 VFD Display Module||Rarkov||Parts||0||23rd August 2003 08:26 PM|
|New To Site?||Need Help?|