What are these round pads on the bottom of a PCB?Can you place vias inside a QFN footprint?Designing footprint for LFCSP CP-8-13 what should be the pad sizeWhat are these exposed copper rectangles for on the mbed NXP LPC1768?Connecting top and bottom SMD component pads using viaIdentifying Feature on VGA PCBHow important is it to track from centre of pad in PCB routing?Copper dimension around the PCB component's hole (pad?)Some pads on a PCB are marked in clusters and I can't understand which one is which

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What are these round pads on the bottom of a PCB?


Can you place vias inside a QFN footprint?Designing footprint for LFCSP CP-8-13 what should be the pad sizeWhat are these exposed copper rectangles for on the mbed NXP LPC1768?Connecting top and bottom SMD component pads using viaIdentifying Feature on VGA PCBHow important is it to track from centre of pad in PCB routing?Copper dimension around the PCB component's hole (pad?)Some pads on a PCB are marked in clusters and I can't understand which one is which






.everyoneloves__top-leaderboard:empty,.everyoneloves__mid-leaderboard:empty,.everyoneloves__bot-mid-leaderboard:empty
margin-bottom:0;









10














$begingroup$


What are these round pads on the bottom of a PCB marked ScX?



I don't think these are test points - this board has some (not in the picture) and they're labelled with TP and the pad size and shape are different.



enter image description here



My best guess is that they're termination pads, but googling it didn't turn up many results so I can't verify that.










share|improve this question











$endgroup$











  • 3




    $begingroup$
    What's a termination pad?
    $endgroup$
    – pipe
    May 8 at 9:35

















10














$begingroup$


What are these round pads on the bottom of a PCB marked ScX?



I don't think these are test points - this board has some (not in the picture) and they're labelled with TP and the pad size and shape are different.



enter image description here



My best guess is that they're termination pads, but googling it didn't turn up many results so I can't verify that.










share|improve this question











$endgroup$











  • 3




    $begingroup$
    What's a termination pad?
    $endgroup$
    – pipe
    May 8 at 9:35













10












10








10


2



$begingroup$


What are these round pads on the bottom of a PCB marked ScX?



I don't think these are test points - this board has some (not in the picture) and they're labelled with TP and the pad size and shape are different.



enter image description here



My best guess is that they're termination pads, but googling it didn't turn up many results so I can't verify that.










share|improve this question











$endgroup$




What are these round pads on the bottom of a PCB marked ScX?



I don't think these are test points - this board has some (not in the picture) and they're labelled with TP and the pad size and shape are different.



enter image description here



My best guess is that they're termination pads, but googling it didn't turn up many results so I can't verify that.







pcb






share|improve this question















share|improve this question













share|improve this question




share|improve this question



share|improve this question








edited May 8 at 11:54









pipe

10.5k4 gold badges27 silver badges59 bronze badges




10.5k4 gold badges27 silver badges59 bronze badges










asked May 7 at 22:51









fandorfandor

1761 silver badge13 bronze badges




1761 silver badge13 bronze badges










  • 3




    $begingroup$
    What's a termination pad?
    $endgroup$
    – pipe
    May 8 at 9:35












  • 3




    $begingroup$
    What's a termination pad?
    $endgroup$
    – pipe
    May 8 at 9:35







3




3




$begingroup$
What's a termination pad?
$endgroup$
– pipe
May 8 at 9:35




$begingroup$
What's a termination pad?
$endgroup$
– pipe
May 8 at 9:35










3 Answers
3






active

oldest

votes


















30
















$begingroup$

As mentioned in some of the comments, these are test pads designed for use with a pogo-pin test fixture, also known as a bed-of-nails test fixture. These fixtures have a specially-shaped array of pogo-pins which press down and make contact with the test pads on the board under test:



enter image description hereenter image description here



These test pads and the test points are probably used in different parts of the manufacturing process. For example, the test points may be used for board-level testing and the test pads may be used for system-level testing. Or, perhaps, the test pads are used for programming and/or debugging firmware, when the device under test is clamped into the bed-of-nails fixture.






share|improve this answer










$endgroup$










  • 1




    $begingroup$
    +1; this answer is much more complete than mine. To the asker: also look at @ThomasWeller's answer, which explains why they might be labelled differently.
    $endgroup$
    – Hearth
    May 8 at 16:09






  • 1




    $begingroup$
    Bed of nails isn’t as popular nowadays. Flying probe, wherein four or so pins attached to a robotic arm connect to the test points, is what is generally used.
    $endgroup$
    – user110971
    May 8 at 18:57






  • 1




    $begingroup$
    @user110971 I don't know about popularity, but I know a LOT of places that still do bed of nails testing
    $endgroup$
    – DerStrom8
    May 8 at 21:50


















20
















$begingroup$

They're called test points. They're places to stick your multimeter probes, or, more commonly, an industrial test jig.






share|improve this answer










$endgroup$














  • $begingroup$
    Hm, I don't think these are test points - this board has some (not in the picture) and they're labelled with TP and the pad size and shape are different.
    $endgroup$
    – fandor
    May 7 at 23:14







  • 11




    $begingroup$
    They may be only for system validation by the manufacturer, whereas the ones labelled TP could be for maintenance purposes? They look exactly like the test points used on a number of boards I've seen and made, so I'd be surprised if they aren't.
    $endgroup$
    – Hearth
    May 7 at 23:17






  • 7




    $begingroup$
    These are the eMMC interface debug points, to connect a custom-made pogo-pin test jig.
    $endgroup$
    – Ale..chenski
    May 8 at 2:59






  • 3




    $begingroup$
    Those are probably there to upload the firmware in the eMMC during production. So it isn't really for testing, but the principle is the same.
    $endgroup$
    – dim
    May 8 at 5:12







  • 2




    $begingroup$
    @fandor That information should have gone into the question. Now you can't accept this answer because it's not correct, while people have outdone themselves and not only written their alternative answers in the comment section, but in the comment section on a different answer! Good luck accepting those!
    $endgroup$
    – pipe
    May 8 at 9:39


















6
















$begingroup$

I think SC could be short for "spring contact" (spring loaded contact), in which case the PCB will be mounted together with some other PCB, similar to a Arduino header, but a different connector type not using male and female pins.



Concept






share|improve this answer










$endgroup$














  • $begingroup$
    Hm, interesting, so the pads would be designed for soldering the SMT spring contacts. It seems the most likely answer considering the size of the pads.
    $endgroup$
    – pipe
    May 9 at 8:23







  • 1




    $begingroup$
    @pipe Not really, the pads look already plated, so they are there to be touched by the "pistons" of spring contacts mounted on a different board (or a bed-of-nails as mentioned in the other answers).
    $endgroup$
    – TooTea
    May 9 at 11:41










  • $begingroup$
    @TooTea The plating looks like the standard ENIG that you can find on the other unsoldered copper on the board. They simply chose not to populate these pins.
    $endgroup$
    – pipe
    May 9 at 11:49












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3 Answers
3






active

oldest

votes








3 Answers
3






active

oldest

votes









active

oldest

votes






active

oldest

votes









30
















$begingroup$

As mentioned in some of the comments, these are test pads designed for use with a pogo-pin test fixture, also known as a bed-of-nails test fixture. These fixtures have a specially-shaped array of pogo-pins which press down and make contact with the test pads on the board under test:



enter image description hereenter image description here



These test pads and the test points are probably used in different parts of the manufacturing process. For example, the test points may be used for board-level testing and the test pads may be used for system-level testing. Or, perhaps, the test pads are used for programming and/or debugging firmware, when the device under test is clamped into the bed-of-nails fixture.






share|improve this answer










$endgroup$










  • 1




    $begingroup$
    +1; this answer is much more complete than mine. To the asker: also look at @ThomasWeller's answer, which explains why they might be labelled differently.
    $endgroup$
    – Hearth
    May 8 at 16:09






  • 1




    $begingroup$
    Bed of nails isn’t as popular nowadays. Flying probe, wherein four or so pins attached to a robotic arm connect to the test points, is what is generally used.
    $endgroup$
    – user110971
    May 8 at 18:57






  • 1




    $begingroup$
    @user110971 I don't know about popularity, but I know a LOT of places that still do bed of nails testing
    $endgroup$
    – DerStrom8
    May 8 at 21:50















30
















$begingroup$

As mentioned in some of the comments, these are test pads designed for use with a pogo-pin test fixture, also known as a bed-of-nails test fixture. These fixtures have a specially-shaped array of pogo-pins which press down and make contact with the test pads on the board under test:



enter image description hereenter image description here



These test pads and the test points are probably used in different parts of the manufacturing process. For example, the test points may be used for board-level testing and the test pads may be used for system-level testing. Or, perhaps, the test pads are used for programming and/or debugging firmware, when the device under test is clamped into the bed-of-nails fixture.






share|improve this answer










$endgroup$










  • 1




    $begingroup$
    +1; this answer is much more complete than mine. To the asker: also look at @ThomasWeller's answer, which explains why they might be labelled differently.
    $endgroup$
    – Hearth
    May 8 at 16:09






  • 1




    $begingroup$
    Bed of nails isn’t as popular nowadays. Flying probe, wherein four or so pins attached to a robotic arm connect to the test points, is what is generally used.
    $endgroup$
    – user110971
    May 8 at 18:57






  • 1




    $begingroup$
    @user110971 I don't know about popularity, but I know a LOT of places that still do bed of nails testing
    $endgroup$
    – DerStrom8
    May 8 at 21:50













30














30










30







$begingroup$

As mentioned in some of the comments, these are test pads designed for use with a pogo-pin test fixture, also known as a bed-of-nails test fixture. These fixtures have a specially-shaped array of pogo-pins which press down and make contact with the test pads on the board under test:



enter image description hereenter image description here



These test pads and the test points are probably used in different parts of the manufacturing process. For example, the test points may be used for board-level testing and the test pads may be used for system-level testing. Or, perhaps, the test pads are used for programming and/or debugging firmware, when the device under test is clamped into the bed-of-nails fixture.






share|improve this answer










$endgroup$



As mentioned in some of the comments, these are test pads designed for use with a pogo-pin test fixture, also known as a bed-of-nails test fixture. These fixtures have a specially-shaped array of pogo-pins which press down and make contact with the test pads on the board under test:



enter image description hereenter image description here



These test pads and the test points are probably used in different parts of the manufacturing process. For example, the test points may be used for board-level testing and the test pads may be used for system-level testing. Or, perhaps, the test pads are used for programming and/or debugging firmware, when the device under test is clamped into the bed-of-nails fixture.







share|improve this answer













share|improve this answer




share|improve this answer



share|improve this answer










answered May 8 at 11:12









DerStrom8DerStrom8

15.3k6 gold badges31 silver badges65 bronze badges




15.3k6 gold badges31 silver badges65 bronze badges










  • 1




    $begingroup$
    +1; this answer is much more complete than mine. To the asker: also look at @ThomasWeller's answer, which explains why they might be labelled differently.
    $endgroup$
    – Hearth
    May 8 at 16:09






  • 1




    $begingroup$
    Bed of nails isn’t as popular nowadays. Flying probe, wherein four or so pins attached to a robotic arm connect to the test points, is what is generally used.
    $endgroup$
    – user110971
    May 8 at 18:57






  • 1




    $begingroup$
    @user110971 I don't know about popularity, but I know a LOT of places that still do bed of nails testing
    $endgroup$
    – DerStrom8
    May 8 at 21:50












  • 1




    $begingroup$
    +1; this answer is much more complete than mine. To the asker: also look at @ThomasWeller's answer, which explains why they might be labelled differently.
    $endgroup$
    – Hearth
    May 8 at 16:09






  • 1




    $begingroup$
    Bed of nails isn’t as popular nowadays. Flying probe, wherein four or so pins attached to a robotic arm connect to the test points, is what is generally used.
    $endgroup$
    – user110971
    May 8 at 18:57






  • 1




    $begingroup$
    @user110971 I don't know about popularity, but I know a LOT of places that still do bed of nails testing
    $endgroup$
    – DerStrom8
    May 8 at 21:50







1




1




$begingroup$
+1; this answer is much more complete than mine. To the asker: also look at @ThomasWeller's answer, which explains why they might be labelled differently.
$endgroup$
– Hearth
May 8 at 16:09




$begingroup$
+1; this answer is much more complete than mine. To the asker: also look at @ThomasWeller's answer, which explains why they might be labelled differently.
$endgroup$
– Hearth
May 8 at 16:09




1




1




$begingroup$
Bed of nails isn’t as popular nowadays. Flying probe, wherein four or so pins attached to a robotic arm connect to the test points, is what is generally used.
$endgroup$
– user110971
May 8 at 18:57




$begingroup$
Bed of nails isn’t as popular nowadays. Flying probe, wherein four or so pins attached to a robotic arm connect to the test points, is what is generally used.
$endgroup$
– user110971
May 8 at 18:57




1




1




$begingroup$
@user110971 I don't know about popularity, but I know a LOT of places that still do bed of nails testing
$endgroup$
– DerStrom8
May 8 at 21:50




$begingroup$
@user110971 I don't know about popularity, but I know a LOT of places that still do bed of nails testing
$endgroup$
– DerStrom8
May 8 at 21:50













20
















$begingroup$

They're called test points. They're places to stick your multimeter probes, or, more commonly, an industrial test jig.






share|improve this answer










$endgroup$














  • $begingroup$
    Hm, I don't think these are test points - this board has some (not in the picture) and they're labelled with TP and the pad size and shape are different.
    $endgroup$
    – fandor
    May 7 at 23:14







  • 11




    $begingroup$
    They may be only for system validation by the manufacturer, whereas the ones labelled TP could be for maintenance purposes? They look exactly like the test points used on a number of boards I've seen and made, so I'd be surprised if they aren't.
    $endgroup$
    – Hearth
    May 7 at 23:17






  • 7




    $begingroup$
    These are the eMMC interface debug points, to connect a custom-made pogo-pin test jig.
    $endgroup$
    – Ale..chenski
    May 8 at 2:59






  • 3




    $begingroup$
    Those are probably there to upload the firmware in the eMMC during production. So it isn't really for testing, but the principle is the same.
    $endgroup$
    – dim
    May 8 at 5:12







  • 2




    $begingroup$
    @fandor That information should have gone into the question. Now you can't accept this answer because it's not correct, while people have outdone themselves and not only written their alternative answers in the comment section, but in the comment section on a different answer! Good luck accepting those!
    $endgroup$
    – pipe
    May 8 at 9:39















20
















$begingroup$

They're called test points. They're places to stick your multimeter probes, or, more commonly, an industrial test jig.






share|improve this answer










$endgroup$














  • $begingroup$
    Hm, I don't think these are test points - this board has some (not in the picture) and they're labelled with TP and the pad size and shape are different.
    $endgroup$
    – fandor
    May 7 at 23:14







  • 11




    $begingroup$
    They may be only for system validation by the manufacturer, whereas the ones labelled TP could be for maintenance purposes? They look exactly like the test points used on a number of boards I've seen and made, so I'd be surprised if they aren't.
    $endgroup$
    – Hearth
    May 7 at 23:17






  • 7




    $begingroup$
    These are the eMMC interface debug points, to connect a custom-made pogo-pin test jig.
    $endgroup$
    – Ale..chenski
    May 8 at 2:59






  • 3




    $begingroup$
    Those are probably there to upload the firmware in the eMMC during production. So it isn't really for testing, but the principle is the same.
    $endgroup$
    – dim
    May 8 at 5:12







  • 2




    $begingroup$
    @fandor That information should have gone into the question. Now you can't accept this answer because it's not correct, while people have outdone themselves and not only written their alternative answers in the comment section, but in the comment section on a different answer! Good luck accepting those!
    $endgroup$
    – pipe
    May 8 at 9:39













20














20










20







$begingroup$

They're called test points. They're places to stick your multimeter probes, or, more commonly, an industrial test jig.






share|improve this answer










$endgroup$



They're called test points. They're places to stick your multimeter probes, or, more commonly, an industrial test jig.







share|improve this answer













share|improve this answer




share|improve this answer



share|improve this answer










answered May 7 at 22:52









HearthHearth

7,7631 gold badge19 silver badges53 bronze badges




7,7631 gold badge19 silver badges53 bronze badges














  • $begingroup$
    Hm, I don't think these are test points - this board has some (not in the picture) and they're labelled with TP and the pad size and shape are different.
    $endgroup$
    – fandor
    May 7 at 23:14







  • 11




    $begingroup$
    They may be only for system validation by the manufacturer, whereas the ones labelled TP could be for maintenance purposes? They look exactly like the test points used on a number of boards I've seen and made, so I'd be surprised if they aren't.
    $endgroup$
    – Hearth
    May 7 at 23:17






  • 7




    $begingroup$
    These are the eMMC interface debug points, to connect a custom-made pogo-pin test jig.
    $endgroup$
    – Ale..chenski
    May 8 at 2:59






  • 3




    $begingroup$
    Those are probably there to upload the firmware in the eMMC during production. So it isn't really for testing, but the principle is the same.
    $endgroup$
    – dim
    May 8 at 5:12







  • 2




    $begingroup$
    @fandor That information should have gone into the question. Now you can't accept this answer because it's not correct, while people have outdone themselves and not only written their alternative answers in the comment section, but in the comment section on a different answer! Good luck accepting those!
    $endgroup$
    – pipe
    May 8 at 9:39
















  • $begingroup$
    Hm, I don't think these are test points - this board has some (not in the picture) and they're labelled with TP and the pad size and shape are different.
    $endgroup$
    – fandor
    May 7 at 23:14







  • 11




    $begingroup$
    They may be only for system validation by the manufacturer, whereas the ones labelled TP could be for maintenance purposes? They look exactly like the test points used on a number of boards I've seen and made, so I'd be surprised if they aren't.
    $endgroup$
    – Hearth
    May 7 at 23:17






  • 7




    $begingroup$
    These are the eMMC interface debug points, to connect a custom-made pogo-pin test jig.
    $endgroup$
    – Ale..chenski
    May 8 at 2:59






  • 3




    $begingroup$
    Those are probably there to upload the firmware in the eMMC during production. So it isn't really for testing, but the principle is the same.
    $endgroup$
    – dim
    May 8 at 5:12







  • 2




    $begingroup$
    @fandor That information should have gone into the question. Now you can't accept this answer because it's not correct, while people have outdone themselves and not only written their alternative answers in the comment section, but in the comment section on a different answer! Good luck accepting those!
    $endgroup$
    – pipe
    May 8 at 9:39















$begingroup$
Hm, I don't think these are test points - this board has some (not in the picture) and they're labelled with TP and the pad size and shape are different.
$endgroup$
– fandor
May 7 at 23:14





$begingroup$
Hm, I don't think these are test points - this board has some (not in the picture) and they're labelled with TP and the pad size and shape are different.
$endgroup$
– fandor
May 7 at 23:14





11




11




$begingroup$
They may be only for system validation by the manufacturer, whereas the ones labelled TP could be for maintenance purposes? They look exactly like the test points used on a number of boards I've seen and made, so I'd be surprised if they aren't.
$endgroup$
– Hearth
May 7 at 23:17




$begingroup$
They may be only for system validation by the manufacturer, whereas the ones labelled TP could be for maintenance purposes? They look exactly like the test points used on a number of boards I've seen and made, so I'd be surprised if they aren't.
$endgroup$
– Hearth
May 7 at 23:17




7




7




$begingroup$
These are the eMMC interface debug points, to connect a custom-made pogo-pin test jig.
$endgroup$
– Ale..chenski
May 8 at 2:59




$begingroup$
These are the eMMC interface debug points, to connect a custom-made pogo-pin test jig.
$endgroup$
– Ale..chenski
May 8 at 2:59




3




3




$begingroup$
Those are probably there to upload the firmware in the eMMC during production. So it isn't really for testing, but the principle is the same.
$endgroup$
– dim
May 8 at 5:12





$begingroup$
Those are probably there to upload the firmware in the eMMC during production. So it isn't really for testing, but the principle is the same.
$endgroup$
– dim
May 8 at 5:12





2




2




$begingroup$
@fandor That information should have gone into the question. Now you can't accept this answer because it's not correct, while people have outdone themselves and not only written their alternative answers in the comment section, but in the comment section on a different answer! Good luck accepting those!
$endgroup$
– pipe
May 8 at 9:39




$begingroup$
@fandor That information should have gone into the question. Now you can't accept this answer because it's not correct, while people have outdone themselves and not only written their alternative answers in the comment section, but in the comment section on a different answer! Good luck accepting those!
$endgroup$
– pipe
May 8 at 9:39











6
















$begingroup$

I think SC could be short for "spring contact" (spring loaded contact), in which case the PCB will be mounted together with some other PCB, similar to a Arduino header, but a different connector type not using male and female pins.



Concept






share|improve this answer










$endgroup$














  • $begingroup$
    Hm, interesting, so the pads would be designed for soldering the SMT spring contacts. It seems the most likely answer considering the size of the pads.
    $endgroup$
    – pipe
    May 9 at 8:23







  • 1




    $begingroup$
    @pipe Not really, the pads look already plated, so they are there to be touched by the "pistons" of spring contacts mounted on a different board (or a bed-of-nails as mentioned in the other answers).
    $endgroup$
    – TooTea
    May 9 at 11:41










  • $begingroup$
    @TooTea The plating looks like the standard ENIG that you can find on the other unsoldered copper on the board. They simply chose not to populate these pins.
    $endgroup$
    – pipe
    May 9 at 11:49















6
















$begingroup$

I think SC could be short for "spring contact" (spring loaded contact), in which case the PCB will be mounted together with some other PCB, similar to a Arduino header, but a different connector type not using male and female pins.



Concept






share|improve this answer










$endgroup$














  • $begingroup$
    Hm, interesting, so the pads would be designed for soldering the SMT spring contacts. It seems the most likely answer considering the size of the pads.
    $endgroup$
    – pipe
    May 9 at 8:23







  • 1




    $begingroup$
    @pipe Not really, the pads look already plated, so they are there to be touched by the "pistons" of spring contacts mounted on a different board (or a bed-of-nails as mentioned in the other answers).
    $endgroup$
    – TooTea
    May 9 at 11:41










  • $begingroup$
    @TooTea The plating looks like the standard ENIG that you can find on the other unsoldered copper on the board. They simply chose not to populate these pins.
    $endgroup$
    – pipe
    May 9 at 11:49













6














6










6







$begingroup$

I think SC could be short for "spring contact" (spring loaded contact), in which case the PCB will be mounted together with some other PCB, similar to a Arduino header, but a different connector type not using male and female pins.



Concept






share|improve this answer










$endgroup$



I think SC could be short for "spring contact" (spring loaded contact), in which case the PCB will be mounted together with some other PCB, similar to a Arduino header, but a different connector type not using male and female pins.



Concept







share|improve this answer













share|improve this answer




share|improve this answer



share|improve this answer










answered May 8 at 15:24









Thomas WellerThomas Weller

4024 silver badges16 bronze badges




4024 silver badges16 bronze badges














  • $begingroup$
    Hm, interesting, so the pads would be designed for soldering the SMT spring contacts. It seems the most likely answer considering the size of the pads.
    $endgroup$
    – pipe
    May 9 at 8:23







  • 1




    $begingroup$
    @pipe Not really, the pads look already plated, so they are there to be touched by the "pistons" of spring contacts mounted on a different board (or a bed-of-nails as mentioned in the other answers).
    $endgroup$
    – TooTea
    May 9 at 11:41










  • $begingroup$
    @TooTea The plating looks like the standard ENIG that you can find on the other unsoldered copper on the board. They simply chose not to populate these pins.
    $endgroup$
    – pipe
    May 9 at 11:49
















  • $begingroup$
    Hm, interesting, so the pads would be designed for soldering the SMT spring contacts. It seems the most likely answer considering the size of the pads.
    $endgroup$
    – pipe
    May 9 at 8:23







  • 1




    $begingroup$
    @pipe Not really, the pads look already plated, so they are there to be touched by the "pistons" of spring contacts mounted on a different board (or a bed-of-nails as mentioned in the other answers).
    $endgroup$
    – TooTea
    May 9 at 11:41










  • $begingroup$
    @TooTea The plating looks like the standard ENIG that you can find on the other unsoldered copper on the board. They simply chose not to populate these pins.
    $endgroup$
    – pipe
    May 9 at 11:49















$begingroup$
Hm, interesting, so the pads would be designed for soldering the SMT spring contacts. It seems the most likely answer considering the size of the pads.
$endgroup$
– pipe
May 9 at 8:23





$begingroup$
Hm, interesting, so the pads would be designed for soldering the SMT spring contacts. It seems the most likely answer considering the size of the pads.
$endgroup$
– pipe
May 9 at 8:23





1




1




$begingroup$
@pipe Not really, the pads look already plated, so they are there to be touched by the "pistons" of spring contacts mounted on a different board (or a bed-of-nails as mentioned in the other answers).
$endgroup$
– TooTea
May 9 at 11:41




$begingroup$
@pipe Not really, the pads look already plated, so they are there to be touched by the "pistons" of spring contacts mounted on a different board (or a bed-of-nails as mentioned in the other answers).
$endgroup$
– TooTea
May 9 at 11:41












$begingroup$
@TooTea The plating looks like the standard ENIG that you can find on the other unsoldered copper on the board. They simply chose not to populate these pins.
$endgroup$
– pipe
May 9 at 11:49




$begingroup$
@TooTea The plating looks like the standard ENIG that you can find on the other unsoldered copper on the board. They simply chose not to populate these pins.
$endgroup$
– pipe
May 9 at 11:49


















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