Is automatic gain feature present in these higher power TPA chips? I know some of the low power stuff has it (TPA2016 as an example). As I play with the SMAKN boards I posted, I have noticed that when a song ends, there is no hiss at all, but after a few seconds of quiet on the input I will hear a small amount of hiss appear.
I really need to dig into the datasheets, but you guys are just too helpful
I really need to dig into the datasheets, but you guys are just too helpful
I believe in TI datasheet they say 5% resistors are needed for gainsetting, but they might just mean not to pick more expensive ones
I guess it can't hurt to try. Maybe two 30k in parallel is 15k might be closer match to 20k. I will try tonight. Psyche myself up for some micro soldering. I need a 0.015in tip on my iron.
26dB gain works
I found the proper 20k and 100k resistors to implement 26dB gain. The values were amazingly spot on for such tiny resistors (measured 19.97k and 99.88k). Desoldering and soldering SMT's is a pain...
Anyhow, it works now at the lower 26dB gain.
I found the proper 20k and 100k resistors to implement 26dB gain. The values were amazingly spot on for such tiny resistors (measured 19.97k and 99.88k). Desoldering and soldering SMT's is a pain...
Anyhow, it works now at the lower 26dB gain.
Attachments
I feel like the sound has more dynamic range - it sounds better even. I did not have a problem with on off thump before and I think it became even less noticeable than before with lower gain. Overall, a good upgrade mod to go down to 26dB. I did not listen extensively, just a few CD's as this amp is getting packaged to be sent to a friend in DK.
I have just one poor photo of the (more or less) finished amp, before putting it in the enclosure.
I simply forgot to take detailed photos before delivering the finished mono blocks
Denis
Attachments
10k to mutepin connected from 75k gainsetting resistor on Sanwu when mute is connected during startup, so externally, on Sanwu pcb, gainsetting could be affected if only taking place during startup
After seeing how much "fun" I had desoldering a few SMT parts and swapping them out, I am realizing that I am lacking the tools for the job. Should I invest in an SMT desoldering/solder rework station like this one? Any recommendations from the experts on SMT builds (Dr Mord)?
Or do I need the two prong tweezer type de-soldering iron?
220V/110V 700W YOUYUE 8586 2 in 1 SMD Rework Station Hot Air Gun 700w + soldering iron Better than Atten At8586 + 3 Nozzles-in Electric Soldering Irons from Industry & Business on Aliexpress.com | Alibaba Group
or
http://www.amazon.com/Soldering-Rework-Station-Stand-Nozzle/dp/B01AMC0L2M/
If I want to build more custom SMT based amps, I am going to need more than my trusty 20 year old Weller iron.
Or do I need the two prong tweezer type de-soldering iron?
220V/110V 700W YOUYUE 8586 2 in 1 SMD Rework Station Hot Air Gun 700w + soldering iron Better than Atten At8586 + 3 Nozzles-in Electric Soldering Irons from Industry & Business on Aliexpress.com | Alibaba Group
or
http://www.amazon.com/Soldering-Rework-Station-Stand-Nozzle/dp/B01AMC0L2M/
If I want to build more custom SMT based amps, I am going to need more than my trusty 20 year old Weller iron.
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Actually soldering, desoldering smd is siple with ordinary iron and tweezers. Maybe small package chips are more tricky.
Here is good tutorials, I learn from:
Tangent Tutorials
Here is good tutorials, I learn from:
Tangent Tutorials
I also agree that soldering/desoldering SMD with a normal iron is quite easy down to 0402, but then I do it almost every day.
That yuiha station from Amazon looks like a half decent one. The tips look to be Hakko style, and it will benefit tremendously from purchasing a few genuine Hakko tips, but the stock ones will get you started for sure.
You can also get a hot tweezer hand piece for that station, which is quite handy for SMD resistors, caps, etc. 2 pad devices. You will need to use the hot air gun for the ICs still, I just find the air to be a bit of a PITA because there are usually multiple components near each other, and if you have the air set too high or are using the wrong nozzle, you can reflow and disturb stuff nearby.
I doubt the temperature is accurate, but that really doesn't matter, you just use the numbers as a relative reference.
That yuiha station from Amazon looks like a half decent one. The tips look to be Hakko style, and it will benefit tremendously from purchasing a few genuine Hakko tips, but the stock ones will get you started for sure.
You can also get a hot tweezer hand piece for that station, which is quite handy for SMD resistors, caps, etc. 2 pad devices. You will need to use the hot air gun for the ICs still, I just find the air to be a bit of a PITA because there are usually multiple components near each other, and if you have the air set too high or are using the wrong nozzle, you can reflow and disturb stuff nearby.
I doubt the temperature is accurate, but that really doesn't matter, you just use the numbers as a relative reference.
To be honest I rarely work with lead free, I prefer my electronics to be loaded with toxic heavy metals. I have heard that lead free will cause more rapid wear to tips, but I have personally not used enough of it to have witnessed it myself.
EDIT: Figured I should mention, despite having a nice workstation, I tend to solder a lot of things "in-situ", and so my "go to" iron has actually been a cheap ATTEN SS-50 I got awhile back when sparkfun sold them. Didn't find it on sparkfun anymore, but I did find one on ebay if anyone is interested.
http://www.ebay.com/itm/like/222014026655?ul_noapp=true&chn=ps&lpid=82
or even cheaper
http://www.sainsmart.com/new-roigin...QohG20R-4j5kK3YAI81UFePtU_0Q07OlQEaAgp-8P8HAQ
EDIT: Figured I should mention, despite having a nice workstation, I tend to solder a lot of things "in-situ", and so my "go to" iron has actually been a cheap ATTEN SS-50 I got awhile back when sparkfun sold them. Didn't find it on sparkfun anymore, but I did find one on ebay if anyone is interested.
http://www.ebay.com/itm/like/222014026655?ul_noapp=true&chn=ps&lpid=82
or even cheaper
http://www.sainsmart.com/new-roigin...QohG20R-4j5kK3YAI81UFePtU_0Q07OlQEaAgp-8P8HAQ
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The whole Pb free craze which mandated Pb free electronics has cost billions of dollars lost due to satellite electronics failures. Satellites cost $300M to $1B depending on complexity. What problems? Tin whiskers can grow in lead free solder and the whiskers don't have to grow far to short out tight IC's and other parts. The solution is to not use lead free. But it took 10 years before stuff started failing before people knew this was the cause.
After seeing how much "fun" I had desoldering a few SMT parts and swapping them out, I am realizing that I am lacking the tools for the job. Should I invest in an SMT desoldering/solder rework station like this one? Any recommendations from the experts on SMT builds (Dr Mord)?
Or do I need the two prong tweezer type de-soldering iron?
220V/110V 700W YOUYUE 8586 2 in 1 SMD Rework Station Hot Air Gun 700w + soldering iron Better than Atten At8586 + 3 Nozzles-in Electric Soldering Irons from Industry & Business on Aliexpress.com | Alibaba Group
or
2 in 1 SMD Soldering Hot Air Rework Station + Stand 3 Nozzle 5 Tips 852d+ Iron Yihua - - Amazon.com
If I want to build more custom SMT based amps, I am going to need more than my trusty 20 year old Weller iron.
Yeah, I have been thinking of getting something like this:
https://www.circuitspecialists.com/Tweezer-Style-Soldering-Iron-For-SMD.html.
It should come in handy for desoldering SMT components (caps and resistors). For whatever reasons, these are hard to find. Unfortunately, since I am in Canada, the shipping charge costs way more than the item
I have that ATTEN iron, definitely a highly decent workhorse for the slightly heavier stuff. Only small gripe is the cable's a bit on the stiff side. Can't think why it needs to be so thick for such a low power appliance.
Check this out - I want one!
110v version (it says 220v but power cord is 110v?):
2 in 1 Soldering Welding Iron with Antistatic Desoldering Solder Pump Vacuum Sucker Removal Tool Free Shipping-in Electric Soldering Irons from Industry & Business on Aliexpress.com | Alibaba Group
220v EU version:
EU 2in1 30W 220V Soldering Iron PCB Solder Sucker Desoldering Pump Welding Tool High Quality-in Electric Soldering Irons from Industry & Business on Aliexpress.com | Alibaba Group
110v version (it says 220v but power cord is 110v?):
2 in 1 Soldering Welding Iron with Antistatic Desoldering Solder Pump Vacuum Sucker Removal Tool Free Shipping-in Electric Soldering Irons from Industry & Business on Aliexpress.com | Alibaba Group
220v EU version:
EU 2in1 30W 220V Soldering Iron PCB Solder Sucker Desoldering Pump Welding Tool High Quality-in Electric Soldering Irons from Industry & Business on Aliexpress.com | Alibaba Group