Problems with Ceramic Capacitor SMD In-Circuit Test

I would like to know if someone aleady have problems with Ceramic Capacitors SMD in In-Circuit Test (see below)and how did you solve this problems ? PROBLEMS 1 - Only one kind of capacitor (2n2F), of all capacitors on board, sometimes are open, and if you change its, using the same capacitor from new reel, the In-circuit test approvel this board. 2 - During somewhere of shift one kind of capacitor (2n2F) of all capacitors on board are open.

Our parameter of process are:

Cure of GLUE (side B) with 160�C at 120 sec. Soldering of Components by Machine (side B + PHT) with Pre Heater 153�C, solder bath 245�C and Dip Time less 5 sec

Thank you very much

Adriano Fernandes

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| I would like to know if someone aleady have problems with Ceramic Capacitors SMD in In-Circuit Test (see below)and how did you solve this problems ? | | PROBLEMS | 1 - Only one kind of capacitor (2n2F), of all capacitors on board, sometimes are open, and if you change its, using the same capacitor from new reel, the In-circuit test approvel this board. | 2 - During somewhere of shift one kind of capacitor (2n2F) of all capacitors on board are open.

| | Our parameter of process are: | | Cure of GLUE (side B) with 160�C at 120 sec. | Soldering of Components by Machine (side B + PHT) with Pre Heater 153�C, solder bath 245�C and Dip Time less 5 sec | | Thank you very much | | Adriano Fernandes

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Hi Adriano,

Couple of things I would consider are as follows:

1) Date code of that particular type cap and SPQL in incoming for that particular vendor/type comp.

2)Do u do process characterization for every new comp on your product during feasibility/proto/pre-prod. runs? If yes. then it would narrow down your Root cause analysis regarding date code specific problem for both process(for your end)/comp.vendor.

3) Run a DOE with same process with all NEW process implementation into account.

4)Testing (ICT) parameters can be reviewed.

5) Need special attention/review on all temp./heat cycle spec for that particular comp.

6)SMP footprint and comp leads/contact geometry.

Hope it helps

Regards Kc.

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| | I would like to know if someone aleady have problems with Ceramic Capacitors SMD in In-Circuit Test (see below)and how did you solve this problems ? | | | | PROBLEMS | | 1 - Only one kind of capacitor (2n2F), of all capacitors on board, sometimes are open, and if you change its, using the same capacitor from new reel, the In-circuit test approvel this board. | | 2 - During somewhere of shift one kind of capacitor (2n2F) of all capacitors on board are open. | | | | | | | Our parameter of process are: | | | | Cure of GLUE (side B) with 160�C at 120 sec. | | Soldering of Components by Machine (side B + PHT) with Pre Heater 153�C, solder bath 245�C and Dip Time less 5 sec | | | | Thank you very much | | | | Adriano Fernandes | | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ | | | Hi Adriano, | | Couple of things I would consider are as follows: | | 1) Date code of that particular type cap and SPQL in incoming for that particular vendor/type comp. | | 2)Do u do process characterization for every new comp on your product during feasibility/proto/pre-prod. runs? If yes. then it would narrow down your Root cause analysis regarding date code specific problem for both process(for your end)/comp.vendor. | | 3) Run a DOE with same process with all NEW process implementation into account. | | 4)Testing (ICT) parameters can be reviewed. | | 5) Need special attention/review on all temp./heat cycle spec for that particular comp. | | 6)SMP footprint and comp leads/contact geometry. | | Hope it helps | | Regards Kc. | | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ | | It sounds like you have a chip capacitor cracking problem I suggest you have some of the parts microsectioned to have a look at the inside of the device. Chip Cracking is still a common process problem and normally caused by board flexture not thermal shock.

Bob Willis

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| I would like to know if someone aleady have problems with Ceramic Capacitors SMD in In-Circuit Test (see below)and how did you solve this problems ? | | PROBLEMS | 1 - Only one kind of capacitor (2n2F), of all capacitors on board, sometimes are open, and if you change its, using the same capacitor from new reel, the In-circuit test approvel this board. | 2 - During somewhere of shift one kind of capacitor (2n2F) of all capacitors on board are open. | | Our parameter of process are: | | Cure of GLUE (side B) with 160�C at 120 sec. | Soldering of Components by Machine (side B + PHT) with Pre Heater 153�C, solder bath 245�C and Dip Time less 5 sec | | Thank you very much | | Adriano Fernandes |

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| | I would like to know if someone aleady have problems with Ceramic Capacitors SMD in In-Circuit Test (see below)and how did you solve this problems ? | | | | PROBLEMS | | 1 - Only one kind of capacitor (2n2F), of all capacitors on board, sometimes are open, and if you change its, using the same capacitor from new reel, the In-circuit test approvel this board. | | 2 - During somewhere of shift one kind of capacitor (2n2F) of all capacitors on board are open. | | | | Our parameter of process are: | | | | Cure of GLUE (side B) with 160�C at 120 sec. | | Soldering of Components by Machine (side B + PHT) with Pre Heater 153�C, solder bath 245�C and Dip Time less 5 sec | | | | Thank you very much | | | | Adriano Fernandes | | | |

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