Help identifying this smd component
- Thread starter mckenzie
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Could be a capacitor. I am not aware of any color significance .
JR
JR
Looks no taller than a resistor would be, and i've yet to encounter any ceramic caps that are SO low-profile. And the smallest ones i've seen any markings on were 1206-sized, and very much the exception rather than the rule.
I'm still voting for (possibly fusible) resistors, in series with the +/- supplies to those apparently quad VCA's.
Are you having any problems with the device containing these? Or is this just idle curiosity?
Thanks yes I should have said the package size is 0805. Yes the green colour makes me think perhaps something fusible.
They're not connected directly to those VCA's, they connect through via's to the other side but I've yet to trace where.
It's my Elektron analog rytm drum machine, last pic is part of the compressor section which is working fine.
A cap exploded its electrolyte all over the Low Tom section which is where another one of these mystery components is, see attached pic. I've already replaced the offending electrolytic caps + the 4 IC's & 2 tantalums to the right of the VCA's after cleaning up the area. Most of the LT section is now working again but not 100%, I need to replace those VCA's & this green component next. Obviously no schematic available.
They're not connected directly to those VCA's, they connect through via's to the other side but I've yet to trace where.
It's my Elektron analog rytm drum machine, last pic is part of the compressor section which is working fine.
A cap exploded its electrolyte all over the Low Tom section which is where another one of these mystery components is, see attached pic. I've already replaced the offending electrolytic caps + the 4 IC's & 2 tantalums to the right of the VCA's after cleaning up the area. Most of the LT section is now working again but not 100%, I need to replace those VCA's & this green component next. Obviously no schematic available.
Attachments
Well, you COULD also measure some voltages and see if anything odd is happening on that side, before shotgunning all the chips there...
https://mediadl.musictribe.com/download/documents/coolaudio/docs/Datasheet_CA_V2164D-M.pdf
You can find the pinout in the datasheet linked above. It would make most sense if those resistors were, as i mentioned, in series with the power supply rails of those chips (in groups, though).
If you say electrolyte corrosion is the most likely suspect, why necessarily even consider the VCA's themselves are busted? It might just be some PCB tracks that are no-longer-great? If anything, pulling the chips might just damage those further - the soldering on that green resistor in this second photo, looks not-quite-factory, and i think i can spot some corrosion at least on the copper leaving its left terminal.
https://mediadl.musictribe.com/download/documents/coolaudio/docs/Datasheet_CA_V2164D-M.pdf
You can find the pinout in the datasheet linked above. It would make most sense if those resistors were, as i mentioned, in series with the power supply rails of those chips (in groups, though).
If you say electrolyte corrosion is the most likely suspect, why necessarily even consider the VCA's themselves are busted? It might just be some PCB tracks that are no-longer-great? If anything, pulling the chips might just damage those further - the soldering on that green resistor in this second photo, looks not-quite-factory, and i think i can spot some corrosion at least on the copper leaving its left terminal.
Yup possibly a flame proof resistor, if so it would probably measure 33 ohms.
Did you try asking the manufacturer?
JR
Did you try asking the manufacturer?
JR
Could be, in the first photo for example, 33nF additional filter caps between pins 8-9 (Gnd - V-) and 8-16 (Gnd - V+) of the V2164’s power rails - easy to check with a meter to see if they’re directly connected to and across those pins of the IC’s (or to any other pins) and also test them for capacitance or see if they’re in series with any supply lines.
The colour may be a voltage code of capacitors or wattage if resistors. The green one in the second picture seems to have shards of metal around it and the soldering doesn’t look factory as Khron mentioned.
The colour may be a voltage code of capacitors or wattage if resistors. The green one in the second picture seems to have shards of metal around it and the soldering doesn’t look factory as Khron mentioned.
more like this,
https://nl.mouser.com/datasheet/2/447/KEM_T2009_T495-3316993.pdf
Tantalum Surface Mount Capacitors – Low ESR
https://nl.mouser.com/datasheet/2/447/KEM_T2009_T495-3316993.pdf
Tantalum Surface Mount Capacitors – Low ESR
There's no continuity on them with any surrounding components on the top layer of the board including the IC's & no they all read 1.6k across them.
Yes could test VCA voltages but they do need to come off as the electrolyte is still caked underneath them which you cant really see in the pics. Still waiting to hear back from Elektron.
Yes could test VCA voltages but they do need to come off as the electrolyte is still caked underneath them which you cant really see in the pics. Still waiting to hear back from Elektron.
Is the circuit misbehaving or is this a curiosity pursuit (nothing wrong with curiosity)?
JR
JR
Cqwet Dbdfte
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The "33" sure looks like PTC resistors.
They come in quite a few different shapes.
They come in quite a few different shapes.
As above I've replaced some of the components already & the LT has come back life but not 100% as the attack & decay aren't present properly. Hopefully more cleaning & replacement of the VCA's will fix it. I just wanted to be prepared in case the green component is damaged too.
Thanks this might be a thing as it does have an auto calibration procedure that takes temperatures into account
You could put DC volts meter across them and see if the voltage across (if any) drops as the unit warms up - if they’re PTC the resistance (and voltage) will go up as your temperature rises, if NTC it will go down - although some PTC switching thermistors go down a little initially and then increase rapidly in resistance once crossing over the transition temperature. The measure of 1K6 at room temp indicates it likely falls to 33 Ω at operating temperature.
If a thermistor likely it’s an NTC inrush surge protector in line with supply rails.
PTC’s can be used as inline protection in the event the temperature crosses the threshold - low resistance while operating, high in event of excess current.
If a thermistor likely it’s an NTC inrush surge protector in line with supply rails.
PTC’s can be used as inline protection in the event the temperature crosses the threshold - low resistance while operating, high in event of excess current.
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TE and Littlefuse do thermistors that color
ERJ-T06 maybe - page 11 Panasonic line catalog:
https://datasheet.octopart.com/ERA-6YEB102V-Panasonic---ECG-datasheet-14434274.pdf
https://datasheet.octopart.com/ERA-6YEB102V-Panasonic---ECG-datasheet-14434274.pdf
Or one of the ERAS on page 12 - the 33 not listed but if discontinued may have been one of those. Used for temperature compensation. Depends on location in the circuit as to what functions they have and what type they may be.
