I agree. I'm a very happy customer of Tom's, and I just don't see any of this as an issue. He can run his business how he chooses.
Jack all. I know. I still don't see any need to shoot myself in the foot on purpose from the start.
I am certainly planning to stay out of courtrooms to the extent possible. Only the lawyers win there.
Your request to include schematics has been duly noted.
Topic? Ah yes humilating me for slow progress
Well. We can always return to that, yes.
Tom
Yep. The LME49710NA, which is now discontinued by TI, has been replaced by the LME49720NA. The '720 is the dual version of the '710. The unused channel is configured as a buffer with its input grounded. It does not participate in the circuit (aside from increasing the supply current a bit).
I got tired of winding output inductors, so I had a bunch custom made for me. The new inductors are smaller (both in inductance and physical size) so they do not fit in Rev. 2.2 and below. Rev. 2.3 uses the new inductor.
There's also an additional RC in the RFI/EMI filter. It shaves off a little bandwidth (66 kHz vs 85 kHz) in exchange for a bit better RF immunity.
There were no changes to anything that matters within the audio band from Rev. 2.2 to 2.3.
They were at the time you bought them. Unfortunately TI discontinued the LME49710, which prompted me to up-rev the board.
There's nothing wrong with Rev. 2.2. Just make sure you get the LME49710NA on order before stock runs out. I have a handful of them that I can part with to those who have MOD86 Rev. 1.x, 2.0, or 2.2. I do not have any of the LME49710HA (TO-99 package) for Rev. 2.1.
Tom
Yep. The discontinuance notice on Mouser says last time to buy (for Mouser) is Aug. 7th, 2018. TI's distributor inventory tracker (on ti.com) says Mouser sits on all world-wide inventory (except for Compel in Europe which has 158 of the NA and Newark/Asia which has 120ish of the HA). Mouser has 1600 left of the NA. If I recall correctly, Mouser has to order in batches of 2500 from TI and I seem to recall that Mouser wants you to order a substantial quantity (>100) for them to buy more from TI.
If you need the LME49710, I suggest getting it now. I have a few that I can part with, but once they're gone they are gone. I'm not looking to become a True North version of Mouser.
Tom
If you need the LME49710, I suggest getting it now. I have a few that I can part with, but once they're gone they are gone. I'm not looking to become a True North version of Mouser.
Tom
Adapters and some little bit of research
even TI stock these kind of passive parts and below are few copy of examples from their site.Attachments
I recommend that 2.1 owners build and enjoy their amps.
I do not have any control over which ICs Texas Instruments chooses to discontinue. I can only deal with it when it happens and I am doing that to the best of my ability.
The National Semiconductor products are qualified to run for ten years without failure at the worst case operating conditions. In the MOD86, they're running way below their worst case spec., thus I expect them to last much longer than ten years.
Tom
Adapters and some little bit of research
I've used the green one (TI P/N: DIP-ADAPTER-EVM). It's rock solid. It even comes with the pin strips so you can create DIPs from just about any SMD package.
Tom
Unless you get the rare early-life failure, do something bad to a circuit, or abuse it, solid-state electronics will last a very long time. We're not talking about vacuum tubes or phono cartridges. That said, it wouldn't hurt to have a spare or two just in case, if it makes you sleep better.
Ok, finishing up a R2.1 build with the TO-99 can.
I understand that TI deviated from normal practice by marking Pin 8 instead of Pin 1 on the Can.
Did I understand correctly that Pin 1 is marked on the board, therefore when "Looking down from the top", I should rotate the Can "Clockwise" one pin, then drop in and solder in place?
I understand that TI deviated from normal practice by marking Pin 8 instead of Pin 1 on the Can.
Did I understand correctly that Pin 1 is marked on the board, therefore when "Looking down from the top", I should rotate the Can "Clockwise" one pin, then drop in and solder in place?
Attachments
This is why we don't use the LME49710HA anymore. Normal practice on the TO-99 can is to mark PIN 8. TI follows the same convention as everybody else on the TO-99. This convention is to mark PIN 8.
I follow this convention too and have marked PIN 8 with the drawing of a tab on the silk screen outline.
Thus, the TO-99 in the image above (and attached here with text) is off by one pin. You need to rotate it 45º CCW such that the metal tab of the package aligns with the tab drawn on the silk screen outline.
Tom
Normal practice on the TO-99 can is to mark PIN 8. TI follows the same convention as everybody else on the TO-99. This convention is to mark PIN 8.I follow this convention too and have marked PIN 8 with the drawing of a tab on the silk screen outline.
Thus, the TO-99 in the image above (and attached here with text) is off by one pin. You need to rotate it 45º CCW such that the metal tab of the package aligns with the tab drawn on the silk screen outline.
Tom
Attachments
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