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LC TDK 699-0153 PSU Reference

SuperSVGA

Well-known member

LC TDK 699-0153 PSU​

Since there doesn't seem to be a lot of information on these LC power supplies, I thought I would share what I've been working on the past few months.

My next goal is figuring out what everything on the board does in order to ease diagnosis, unfortunately I don't know much about SMPS or EE in general, so if anyone has any insights feel free to share. I vaguely understand what's going on but not enough to determine how specific voltages are sourced.
Also if anyone can determine the specs of the two transformers, let me know.

Board Components​

All the components on the board, with whatever specs I could determine. I wasn't able to identify most of the diodes.
Capacitors​
Loc​
Capacitance​
Voltage​
Type​
Temp​
Lead​
Height​
Diameter​
C10.22uF250VX1 Safety23.5mm19.7mm24.9mm
C20.1uF250VX1 Safety22.9mm16mm24.6mm
C33.3nF400VCeramic Safety7.2mm14.7mm13.4mm
C43.3nF400VCeramic Safety7.2mm14.7mm13.4mm
C5180uF385VElectrolytic85°C10.5mm25mm30mm
C60.01uF630VMetal Film12mm
C88.2uF50VElectrolytic105°C5.15mm10.8mm5.25mm
C90.001uFPolyester Film4.5mm
C100.047uF50VPolyester Film6.7mm
C113.3nFPolyester Film4.5mm
C123.3nF400VCeramic Safety7.2mm14.7mm13.4mm
C133.3nF400VCeramic Safety7.2mm14.7mm13.4mm
C140.01uFPolyester Film6mm5mm
C511000uF10VElectrolytic105°C5.25mm21.9mm10mm
C521000uF10VElectrolytic105°C5.25mm21.9mm10mm
C53270uF25VElectrolytic105°C3.8mm19.9mm8mm
C54270uF25VElectrolytic105°C3.8mm19.9mm8mm
C551000uF10VElectrolytic105°C5.25mm21.9mm10mm
C5656uF25VElectrolytic3mm4.8mm
C570.1uF63VMetal Film
C6047uF25VElectrolytic105°C4.7mm
C610.001uF250VPolyester Film
C620.22uF63VMetal Film8.7mm
C64270uF10VElectrolytic
C660.001uF250VPolyester Film
Resistors​
Loc​
Resistance​
Power​
Tolerance​
R11MΩ1/4W (250mW)±5%
R3150KΩ1/2W (500mW)±5%
R4150KΩ1/2W (500mW)±5%
R5120KΩ1/2W (500mW)±5%
R639Ω1/8W (125mW)±5%
R7120KΩ1/8W (125mW)±5%
R813KΩ1/8W (125mW)±1%
R95.6KΩ1/8W (125mW)±1%
R10260Ω1/8W (125mW)±5%
R11120Ω1/8W (125mW)±5%
R120.22Ω1/2W (500mW)±5%
R13120Ω1/8W (125mW)±5%
R14150KΩ1/8W (125mW)±5%
R150.22Ω1/2W (500mW)±5%
R1610KΩ1/8W (125mW)±5%
R5127Ω1/2W (500mW)±5%
R54460Ω1/8W (125mW)±5%
R5710KΩ1/8W (125mW)±5%
R5822Ω1/8W (125mW)±5%
R596.8Ω1/8W (125mW)±5%
R6112KΩ1/8W (125mW)±1%
R622.2KΩ1/8W (125mW)±5%
R63220KΩ1/4W (250mW)±5%
R64100Ω1/4W (250mW)±5%
R662.2KΩ1/8W (125mW)±5%
Diodes​
Loc​
Identifier​
Type​
CR1KBP06M 3N250Bridge Rectifier
CR2
CR32 2G 1DF
CR424BZener
CR562BZener
CR51C82MBarrier Diode
CR52B82MBarrier Diode
CR532 2G 1DF
CR54Zener
CR55Zener
CR56Zener
CR572 2G 1DF
Other Components​
Loc​
Name​
Identifier​
F12A 250V T2A
IC1Power ICM51996P
IC51Voltage RegulatorC78N05
IC53OptocouplerSharp PC111
IC54Shunt RegulatorHA17431P
IC55ThyristorNEC 8P2
L1Power Choke?290A P27
L51Inductor - 2.2uH2R2M
L52Inductor - 4.7uH4R7M
L53Inductor - 2.4uH?
Q1MOSFETK1024
R2Thermistor16D-9
R56Potentiometer202
T1TransformerTDK MT1311 M92411
T51TransformerT29 MX
24AWG Solid Wire
5 Pin LC Power

Unpopulated Board Photos​

Images of the board with all the components removed.
front.pngback-1.png

Populated Board Photo​

A picture of a fully populated board, with replaced secondary capacitors.
IMG_2667.png

Redrawn Board Photos​

The PCB redrawn, mostly accurate.
Gerber files are also attached in the post.
PCB-TestFront.JPGPCB-TestBack.JPG

Board Schematic​

A rough schematic of the board. Hopefully it's somewhat readable.
Schematic_TDK 699-0153.png
 

Attachments

  • TDK-LCv1.zip
    43.4 KB · Views: 65
Thank you so much for this. I recently obtained an LCIII. I recapped the power supply but I'm getting low voltage on the -5V rail. Hopefully this helps me track down the problem!
 

SuperSVGA

Well-known member
Correction to resistor R10, I believe it's actually supposed to be a 27KΩ resistor. I guess the first board I was looking at was discolored a bit.
Also R54 should be 470Ω, not 460Ω
 
Last edited:

devius

Member
This is great! I also recently drew the schematic for a TDK PSU, but it’s part number 614-0003. Seems similar enough to this one though. I can share it as well if there’s interest.
 

dan.dem

Well-known member
Thank you SuperSVGA this is a great step to successful repairs of the LC power supplies! While replacing the PS with a modern one is feasible, keeping the original ones working feels more satisfying to me.

Please, can someone try to explain the function of the circuitry? This may hint about the missing component specs.
My own knowledge is more (i.e. less) than rusty.
Anyway, I would like to start discussing the schematic myself, even if there are more questions marks than useful information. Probably it provokes some, very welcome, corrections.

Starting with the two fuses U1 and U2, I can only guess one is quicker.
Then I see a filter consisting of C1, a double choke L1, and C2.
?? R1 makes sure, there is always a minimal load on the input circuit, and slightly dampens the CLC-filter??
C3 and C4 are actual in series and ?? make the mains voltage symmetrical to the device ground ??
CR1 is KBP06G, a 600V 1.5 A bridge rectifier.

Probably, someone more competent may take over. Thank you!
 

dan.dem

Well-known member
I probably should have made that more clear, there's only one fuse, but the holder is two parts making the symbol two sections.
Oh, sorry, I misread this.
Anyway, my hope is that a better understanding of the circuitry leads to recommended procedures for error tracing and repair.
This PS isn't a too complicated, and doesn't need very expensive equipment to repair - like a logic board does.

My hope is we can build up some competence here necessary for reviving classic Mac's PS.
 

Bit-Worker

New member
Hi Everybody!

I have just gotten an LC II with a dead power supply, none of the voltages are right, they are mostly around 1-2V, nowhere near what they should, and I would like to attempt to repair.
I never had Mac LCs before, but this PSU is so cute and pretty simple, its amazing!

Thanks *SuperSVGA* for posting this info! It's priceless!

And sharing this info, to be able to fix old gear, does more for the planet than charging for grocery plastic bags... :D:):D
 

Mauk

New member
Hello there
I have an old LC (32 years old) and am trying to repair the PSU at the moment.
Hopefully all goes well:)
 

Phipli

Well-known member
Pretty seriously covered here, but since I've already collected the data and also recorded the series and make (series only for the Nichicons), I'll post it and my "map" here.

20230729_175325.jpg1690660055280.png
 

bnilsson

New member
I have a Mac LC from mid 90's, I am trying to revive it.

The TDK PS was dead to start, came to life after a few hours (as old electrolytic capacitors sometimes do).
Then it suddenly died again.
I read this thread with great interest.

Replaced all electrolytic caps, the PC came back to life but died again.
Overvoltage 14V/6V or nothing (tick-tick) dependent on the trimmer pot setting.
Replaced the optocoupler. No good.
Replaced the shunt regulator. No good.

Looking at the PCB, it looked strange and icky.
I rinsed the PCB in isopropanol a few times, the liquid in the bucket became severely yellow.
I wiped it off and let it dry.

Started the PS, now it worked perfectly.

The old capacitors had leaked their electrolyte onto a thick layer on the PCB, shorting out all control circuitry.

Lesson learned.

BN
 
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