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    #21
    Re: Chimei DAC-19M009 Power Supply problems

    Can't find any 'GE series' on Panasonic site.

    Did find a discontinued 'NHE' series that has a GE 'series code' in the part number.
    Also, a search on '76P4' yields a pdf about transition from NHE to NHG series.

    Guess I'll give the Nichicon a try...

    Comment


      #22
      Re: Chimei DAC-19M009 Power Supply problems

      Originally posted by plugh
      Another Chimei DAC-19M009 here...

      not mine, a friends; he said display went black.

      Told him to try switching dvi vs vga; no change.
      Told him to use flashlight; can see ghost image.
      Told him to adjust bright/contrast;
      ... with control turned down display sometimes lights on powerup up.

      He opened unit up, pulled PS board, brought it over.
      (It is the same board and rev as in preceding post)
      Inspection reveals board discoloration around P605 inverter ICs,
      and 3 * CapXon 220uF 25V 105C 'KF' caps with bowed tops.
      (one by glass fuse, one between horiz cap and vert resistor,
      one between large green cap and regulator in above pic)

      Diode checked the P605's - they seem OK.
      (thanks for the datasheet pointer above)

      Another thread here gave pointer to CapXon
      http://www.capxongroup.com/en/prod_all_cat_full.aspx
      The 'KF' datasheet says 220uF 25V is low impedance, 8x11.5

      A local warehouse outlet (MCM Electronics) listed two 220uF 25V radial caps
      31-7090 - Capacitor 25V 220uf 105c HI Temp,radial (8D X 11.5l MM) $1.09
      31-5550 - Capacitor 25V 220uf Low ESR Hitemp, Hifreq. Rad. 8dx15l MM $1.89
      unfortunately the 5550's were on backorder (21 days out), but 35V wasn't
      31-5685 - Capacitor 35V 220uf Low ESR Hitemp, Hifreq. Rad. 8dx20l MM $2.19
      (these are a LOT taller than the CapXon's but will still fit ok)

      web-ordered and picked-up 3* 7090 and 3* 5685

      Upon inspection, 5685's are Nichicon 'PL' series.

      Markings on 7090's are 220uF 25V 105C GE with 76P4 stamped on side and
      'M in a box' symbol (M looks more like a capital Sigma rotated 90 degrees)

      Anyone know who / what this cap is? Specs / datasheet?

      Or should I just go with the Nichicons? Note spec diffs:
      CapXon KF 25V
      ---ripple 550mA rms at 105C 100KHz
      ---impedance 0.15 ohm at 20C 100KHz
      Nichicon PL 35V
      ---ripple 795mA rms at 105C 10KHz~200KHz
      ---impedance 0.085 ohm at 20C 100KHz

      Thanks!
      The usual recommendation is to order from a reputable distributor.

      For example, Digikey sells Panasonic FM 220uF 25Volt low ESR caps P12383-ND EEU-FM1E221 for $.33 each. Shipping will cost about $2.00. The monetary savings are marginal for three caps, but Capxon are commonly referred to a 'Crapxon' for their high failure rate. Those with experience usually replace ALL of them they find. Typically, this will run under $10 (including shipping) from Digikey, and you don't have to spend time trying to figure out what you actually received. (For best delivery time, specify USPS First Class Mail. Parts ordered today will be delivered Friday.)

      PlainBill
      For a number of reasons, both health and personal, I will no longer be active on this board. Any PMs asking for assistance will be ignored.

      Never be afraid to try something new. Remember, amateurs built the ark. Professionals built the Titanic.

      Comment


        #23
        Re: Chimei DAC-19M009 Power Supply problems

        Replaced the three 220uF's with the Nichicon's, reassembled, powered up - Works again!

        Many thanks; this forum is a great resource!

        The usual recommendation is to order from a reputable distributor.
        Go to their site, click on About Us. MCM is one of the member companies in a large multi-national corporation.

        No I don't work for them. I simply prefer to deal with a local Brick & Mortar (rare is this market). Having said that, I WAS quite disappointed when I went there this time (been a couple years since last visit). They have closed their show-room and are now purely a warehousing / distribution operation.

        Last time around, I went in the show room and talked with the sales reps. They would pull parts from the warehouse while you were there, you could inspect them, check alternatives, actually "shop"... Now it is ONLY web or phone orders, with a three hour turnaround for will-call orders. Still nice having them up the road, but they've lost some of their appeal to me. Oh well...

        (I've bought from Digi-key before, but the finger twiddling shipping wait drives me nuts when I'm in the middle of something.)

        First eye checks out 20/20! Surgery on other eye Jun 23rd.
        Had both my eyes done a few years ago. Most amazing thing to me after the op wasn't the improved vision but the COLORs. I'd gotten so used to seeing a washed out hazy version of the world, seeing bright vivid colors was an unexpected thrill!
        Last edited by plugh; 06-16-2010, 04:15 PM.

        Comment


          #24
          Re: Chimei DAC-19M009 Power Supply problems

          Originally posted by plugh
          Had both my eyes done a few years ago. Most amazing thing to me after the op wasn't the improved vision but the COLORs. I'd gotten so used to seeing a washed out hazy version of the world, seeing bright vivid colors was an unexpected thrill!
          I had the same reaction!!! A few hours after the surgery we took the shield off to put in eye drops. Suddenly colors were more vivid with my left eye.

          I have a clear plastic computer case on my desk. The fans have UV LEDS in them. With my right eye I can barely see them; with the left eye they are quite bright. I understand a rainbow will even have an extra band (if we ever get rain here).

          PlainBill
          For a number of reasons, both health and personal, I will no longer be active on this board. Any PMs asking for assistance will be ignored.

          Never be afraid to try something new. Remember, amateurs built the ark. Professionals built the Titanic.

          Comment


            #25
            Re: Chimei DAC-19M009 Power Supply problems

            Firstly, what a great site.
            I have managed to rescue one Viewsonic from landfill, with the help of this site, and now have a second that I'm hoping someone can help with.

            I have a VX2235WM that has a DAC 19M009 supply as pictured in some of the earlier posts.
            I have taken the opportunity to replace all the caps, (although none were showing any signs of distress), and gone over any suspect solder joints.

            I can measure 320vDC across the capacitor (yes NZ is 230VAC), but there is nothing on the connectors, or any of the components on the low voltage side of the inverter.

            The switching FET that drives the transformer seemed okay, but to be sure I replaced this, and still nothing.

            Looking underneath all the components around the inverter IC, seem to be at least what they should be, and there seems to be nothing that the smoke has escaped from.

            I was hoping that someone might have a circuit (or some other ideas to chase), as I'm determined to not let it beat me.

            Cheers
            Mark
            Last edited by mcb1; 07-02-2010, 11:13 PM.

            Comment


              #26
              Re: Chimei DAC-19M009 Power Supply problems

              Hello! I suggest that you post pictures (top and bottom) of your power supply/inverter board per the the suggested forum guidelines:

              https://www.badcaps.net/forum/showthread.php?t=1868


              At least this way, some of the more experienced folks (like PlainBill) can mark off some points for you to test. If anything, seeing a photo might jar someone's memory into suggesting specific components to test. Also, it would help to tell us if you hear any sounds or see, say, a quick flash of the power led, etc.

              Without the above info, I would at least try checking for fuses underneath the power board. They would be surface mount and would be labeled FXXX (where XXX is a 3-digit number). Good luck!

              Comment


                #27
                Re: Chimei DAC-19M009 Power Supply problems

                Originally posted by mcb1
                Firstly, what a great site.
                I have managed to rescue one Viewsonic from landfill, with the help of this site, and now have a second that I'm hoping someone can help with.

                I have a VX2235WM that has a DAC 19M009 supply as pictured in some of the earlier posts.
                I have taken the opportunity to replace all the caps, (although none were showing any signs of distress), and gone over any suspect solder joints.

                I can measure 320vDC across the capacitor (yes NZ is 230VAC), but there is nothing on the connectors, or any of the components on the low voltage side of the inverter.

                The switching FET that drives the transformer seemed okay, but to be sure I replaced this, and still nothing.

                Looking underneath all the components around the inverter IC, seem to be at least what they should be, and there seems to be nothing that the smoke has escaped from.

                I was hoping that someone might have a circuit (or some other ideas to chase), as I'm determined to not let it beat me.

                Cheers
                Mark
                Since you are willing to try this on your own, I suggest looking up the datasheet for the SMPS controller. It is an 8 pin IC, usually on the bottom side of the board close to the transformer. Looking at the voltages on the IC and comparing them with the datasheet will help determine if the SMPS is getting appropriate voltages.

                PlainBill
                For a number of reasons, both health and personal, I will no longer be active on this board. Any PMs asking for assistance will be ignored.

                Never be afraid to try something new. Remember, amateurs built the ark. Professionals built the Titanic.

                Comment


                  #28
                  Re: Chimei DAC-19M009 Power Supply problems

                  jetadm123
                  The picture is the same as in #15 (minus the bulging cap)
                  I forgot to include that the fuses were all intact, but thanks for the suggestions.


                  PlainBill
                  I managed to track down the cicuit diagram thanks to some other posts.
                  http://ftpkuban.com/FTP/Manual/ViewSonic/


                  My initial thoughts about where the inverter driver fitted in was wrong, so I'll do some more digging, and check the zener voltage.


                  Thanks
                  very much

                  Mark
                  Last edited by mcb1; 07-04-2010, 09:17 PM.

                  Comment


                    #29
                    Re: Chimei DAC-19M009 Power Supply problems

                    Originally posted by mcb1
                    jetadm123
                    The picture is the same as in #15 (minus the bulging cap)
                    I forgot to include that the fuses were all intact, but thanks for the suggestions.


                    PlainBill
                    I managed to track down the cicuit diagram thanks to some other posts.
                    http://ftpkuban.com/FTP/Manual/ViewSonic/


                    My initial thoughts about where the inverter driver fitted in was wrong, so I'll do some more digging, and check the zener voltage.


                    Thanks
                    very much

                    Mark
                    The LC7575 is a 'green ' SMPS controller. The keys are pins 8, 6, and the 22uF, 50Volt cap. Pin 8 is supposed to dram 1Ma of current through the 10 K resistor until the SMPS starts up. The IC uses that current to charge the cap up to the start-up voltage. It uses that stored charge to run until the T801 starts to provide run current through D807. I've seen a lot of failures on the 'green' SMPS controllers.

                    PlainBill
                    For a number of reasons, both health and personal, I will no longer be active on this board. Any PMs asking for assistance will be ignored.

                    Never be afraid to try something new. Remember, amateurs built the ark. Professionals built the Titanic.

                    Comment


                      #30
                      Re: Chimei DAC-19M009 Power Supply problems

                      PlainBill
                      Thanks for that

                      I was able to download the datasheet, and what an amazing device.
                      It won't be until next week that I have an opportunity to look at the monitor again, but hopefully it should be more obvious with the circuit.

                      I've been in the electronics game for 30 odd years, but for the last 10 or so, I haven't really used a soldering iron in anger.
                      Monitors are something I haven't really been involved with, so its a bit refreshing.

                      Great site and great advice...please keep it up.
                      There is far too much being thrown away, that deserves a new life.


                      Mark

                      Comment


                        #31
                        Re: Chimei DAC-19M009 Power Supply problems

                        Originally posted by mcb1
                        PlainBill
                        Thanks for that

                        I was able to download the datasheet, and what an amazing device.
                        It won't be until next week that I have an opportunity to look at the monitor again, but hopefully it should be more obvious with the circuit.

                        I've been in the electronics game for 30 odd years, but for the last 10 or so, I haven't really used a soldering iron in anger.
                        Monitors are something I haven't really been involved with, so its a bit refreshing.

                        Great site and great advice...please keep it up.
                        There is far too much being thrown away, that deserves a new life.


                        Mark
                        In many ways LCD monitors are ideal for the older people who wish to re-enter electronics repair (provided they remember which end of the soldering iron to grasp). There is an adequate supply of repairable monitors, they are fairly light weight so there is less chance of back strain, most common components are readily available at reasonable prices, and there is a sufficient knowledge base that at least the rudiments of the operation can be discerned easily.

                        PlainBill
                        For a number of reasons, both health and personal, I will no longer be active on this board. Any PMs asking for assistance will be ignored.

                        Never be afraid to try something new. Remember, amateurs built the ark. Professionals built the Titanic.

                        Comment


                          #32
                          Re: Chimei DAC-19M009 Power Supply problems

                          PlainBill

                          Good thoughts.
                          I wasn't intending to make a career of it, but it is something that would suit an age group that prefers repair to replace.

                          I haven't been actively looking for monitors, so I'm not sure what the supply is like.
                          It is certainly something that my son could undertake to pay his way, and I might suggestion it to him.

                          Thanks for the help so far.
                          Mark

                          Comment


                            #33
                            Re: Chimei DAC-19M009 Power Supply problems

                            Hello, This is my first posting. I have read all the posts I can find on the DAC-19M009 Power Supply problems. I have two Viewsonic VG2230 monitors. The first one failed about two months ago and with the help on this thread I was able to get it up and running by replacing the caps and both of the mosfets. I order enough parts to repair the second one as I was sure it was not a matter of if, but when was the second one going to fail. Sure enough yesterday was when..
                            After replacing all the caps and the mosfets I have the 2 second problem. The monitor comes on for a couple of seconds and then goes out. I checked for cold solder joints and found none with the use of a lighted magnifying lamp. I and down to the SMPS controller. Is it possible to make any decent checks with the power/inverter board plug into power and the logic board only. I don't see any easy way of checking voltages on the bottom side of the board, with the lcd leads connected.

                            Comment


                              #34
                              Re: Chimei DAC-19M009 Power Supply problems

                              Originally posted by ray123 View Post
                              Hello, This is my first posting. I have read all the posts I can find on the DAC-19M009 Power Supply problems. I have two Viewsonic VG2230 monitors. The first one failed about two months ago and with the help on this thread I was able to get it up and running by replacing the caps and both of the mosfets. I order enough parts to repair the second one as I was sure it was not a matter of if, but when was the second one going to fail. Sure enough yesterday was when..
                              After replacing all the caps and the mosfets I have the 2 second problem. The monitor comes on for a couple of seconds and then goes out. I checked for cold solder joints and found none with the use of a lighted magnifying lamp. I and down to the SMPS controller. Is it possible to make any decent checks with the power/inverter board plug into power and the logic board only. I don't see any easy way of checking voltages on the bottom side of the board, with the lcd leads connected.
                              Welcome to the forum! I suggest you start a new thread with the title Viewsonic VG2230, since the make and model is what everyone relies on. Also, in your new thread include top and bottom photos of the power supply and logic board per the link below:

                              https://www.badcaps.net/forum/showthread.php?t=1868

                              Comment


                                #35
                                Re: Chimei DAC-19M009 Power Supply problems

                                Originally posted by ray123 View Post
                                I have two Viewsonic VG2230 monitors.
                                The quickest way to narrow this down is to take the "good" power/inverter board and put it in the "bad" one. If you get 2 seconds to black, you know it is the ccfl that is bad. If you don't get 2 seconds to black, then you know something on the inverter board is bad.

                                Do this test and report the finds.

                                I did this very test for 2 identical Benqs and was able to quickly narrow it down to the ccfl being the bad part.
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                                  #36
                                  Re: Chimei DAC-19M009 Power Supply problems

                                  Thank you for the quick response. Great suggestion, just the kind of thing I tell techs when I am helping them. First mistake, assuming I had the same problem, " never assume anything".
                                  I swapped the power/inverter board from working unit to defective unit, same problem. Install latest repaired power board to working monitor, that unit continued to work. It looks like it is the CCFL. I have disassembled the defective monitor to access the CCFL .I found some on Ebay for about $29.00 plus shipping. If anyone has a part number, I would be happy to check some of my sources. I buy from Mouser, Newark, DigiKey and a few others. Without a mfg part number or some specs. It would be a waste of time. The ones on Ebay at least call out the model number. By the way three of the caps that I replaced just a couple of months ago are showing signs of swelling. Not a good sign, I will get more ordered for the next time. These monitors are left on 24/7 as I don't like the power on power off problems that a lot of electronics have and I am accessing my computers all times of the day and night. They have giving me good service otherwise. I try not to buy CapXon as I have not had good luck with them. I did get low esr 105 degree exact matched value capacitor. I had to source from a couple of distributors. By the way guys, I really appreciate this site. Have not worked on LCD monitors, I come from the old tube days and have been working on other types of electronics for about 40 years, I have worked on older CRT type monitors, and I don't like to let any piece of equipment beat me. Thanks again..

                                  Comment


                                    #37
                                    Re: Chimei DAC-19M009 Power Supply problems

                                    Originally posted by ray123 View Post
                                    It looks like it is the CCFL. I have disassembled the defective monitor to access the CCFL.
                                    It may only be one ccfl that is bad, not all of them.

                                    I found some on Ebay for about $29.00 plus shipping.
                                    $29 seems like a lot. I would suggest finding out which one is actually bad. Single replacements could be a lot cheaper than $29.

                                    The ones on Ebay at least call out the model number.
                                    Try (I have no experience with this vendor)

                                    http://ccflwarehouse.com/meyoccla.html


                                    By the way three of the caps that I replaced just a couple of months ago are showing signs of swelling. Not a good sign, I will get more ordered for the next time.
                                    Odd, what brand did you use for the replacement?

                                    The recommended list of caps is at

                                    https://www.badcaps.net/forum/showthread.php?t=2280

                                    If you use digikey a lot, most here will recommend Panasonic FM or FC series as good quality low ESR caps.
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                                      #38
                                      Re: Chimei DAC-19M009 Power Supply problems

                                      Originally posted by ray123 View Post
                                      These monitors are left on 24/7 as I don't like the power on power off problems that a lot of electronics have and I am accessing my computers all times of the day and night.
                                      I hope you at least use the power save/sleep option on your computer. That way, at least the backlights are turned off. It only takes a 1 or 2 seconds for your computer and monitor to "wake" from sleep mode.

                                      Funny, I always turn off all my stuff using a power bar when not in use. Have been doing it for 20+ years and can never attribute a problem due to power on.

                                      The early PC days had hard drives that didn't park the heads when powered off and cause the heads to go skidding across the platters, but that has long been fixed.
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                                        #39
                                        Re: Chimei DAC-19M009 Power Supply problems

                                        Originally posted by retiredcaps View Post
                                        Try (I have no experience with this vendor)

                                        http://ccflwarehouse.com/meyoccla.html
                                        I have purchased from ccflwarehouse before, and they worked great... I ended up buying from their eBay shop instead of the website though because it worked out a little bit cheaper.

                                        Comment


                                          #40
                                          Re: Chimei DAC-19M009 Power Supply problems

                                          Originally posted by ray123 View Post
                                          I found some on Ebay for about $29.00 plus shipping.
                                          Okay, I found that auction. I didn't realize it was for 4 ccfls. I guess you will have spares for the other monitor as well?

                                          When replacing them, be very careful. They are super fragile.
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