- Chip failure and air corrossion products - 2 Updates
- Will RF output (transmitter) be the same wattage as audio output? - 1 Update
- Need *legible* datasheet - 2 Updates
| "pfjw@aol.com" <pfjw@aol.com>: Mar 04 04:40AM -0800 On Saturday, March 4, 2017 at 12:25:50 AM UTC-5, Phil Allison wrote: > ** That should be "Silver Sulphide" = Ag2S > .... Phil True for sterling (.925) silver. Fine silver - what is deposited by electroplating - does not form compounds with sulphur at anything near normal room temperatures. Peter Wieck Melrose Park, PA |
| Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net>: Mar 04 11:10AM -0500 On 03/03/2017 05:11 PM, N_Cook wrote: > seems to trap moisture underneath as though hygroscopic/delequescent or > whatever its called , an oily/ jelly type composition beneath, complete > with green copper carbonate corrossion product Parylene is about the most impervious common coating, but any plastic has orders of magnitude higher gas diffusion rates than any metal. In a humid environment, water will penetrate until the net flux is zero, so if you have nasty hygroscopic corrosive crud underneath, your board is still doomed. Cheers Phil Hobbs -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC Optics, Electro-optics, Photonics, Analog Electronics 160 North State Road #203 Briarcliff Manor NY 10510 hobbs at electrooptical dot net http://electrooptical.net |
| Phil Allison <pallison49@gmail.com>: Mar 04 05:01AM -0800 > Power = V x I " > I had that down before I had pubic hair. The way you worded it was > the subject of my comment. ** You did not READ what I wrote at all - you bullshitting, over-snipping fuckhead. > >"** Its about 2.5kV for a 6L6GC. " > According to http://www.radiostation.ru/tubes/6L6GC-GE.pdf ** Fraid that ref does not mention the spec. You bullshitting fucking idiot. > Plate dissipation doesn't mean shit, ** No, YOU don't mean shit . Cos you are a piece of it. > I am in the "WTF was I thinking" mode now. ** Good, stay there for the rest of your miserable ife. Wot a PITA fucking moron ...... .... Phil |
| jeanyves <jeanyves@nowhere.com>: Mar 04 12:22PM +0100 > 6. What's the project's estimated annual usage? > 7. When is the estimated time-frame of mass production of this project? > I have to go.. I think I heard Ed McMahon at my front door.... answer to their email. you're not asking for samples, you're asking for a readable datasheet. you have a contact there, go on with it until they clearly refuse to answer you. -- Jean-Yves. |
| ohger1s@gmail.com: Mar 04 03:57AM -0800 On Saturday, March 4, 2017 at 6:22:17 AM UTC-5, jeanyves wrote: > answer you. > -- > Jean-Yves. I no longer need the datasheet as I was forced to draw one up from what I could determine on the board. The long story is that this is a 6 channel controller IC used in a Toshiba 58" LCD TV, one that (like most LED back lit LCD TVs), has a propensity to kill LEDs in 2 to 4 thousand hours. I do a lot of LED replacements but don't want them coming back in a few months for the same problem, particularly since the chances of something (like a bonded ribbon failure) going wrong increases every time the screen is taken apart, no matter how carefully. Setting the customer's menu control to a reasonable level doesn't work as any playing around in the menu almost invariably resets the back light level to 100%. The best thing to do is to remove the ability of the end user to set his back light to "retina burn", so I modify the circuit to reduce the back light wattage by about 30%, which still gives a respectable picture but should extend the life exponentially. Since I've been doing this about three years, none have returned. So I sat down and drew out the six channel pin outputs, the six channel current sense inputs, the Vcc, the ground, the PWM input, the enable input, the dc boost gate output, the boost current sense input, etc. until I was left with a few pins that weren't so obvious. On most circuits I raise the value of the source resistors of the LED output mosfets to trick the controller to lower the output, but this version would shut down the back lights if the drive was reduced by 10%, so I had to play with the input side. Most controller ICs are designed with both an analogue (dc) and a PWM input to control LED brightness, and the analogue is often not used (or used as a baseline output) but is terminated with a resistor to ground, or fed in a selected dc from a res/div network. This toshiba used a PWM input for active back light control, and that can only be modified by changing the firmware in the TV, so I turned to the analogue input. In this case, it was terminated to ground through a resistor and capacitor. Changing the value of that resistor got me to 30% reduction of output with no shutdown during the boot sequence. As for O2 Micro, I did return the email and told them that we were an OEM but were no longer interested in their product as we didn't feel comfortable with them if the courtesy of an emailed datasheet was a strain on their "limited resources". |
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