Printed Circuit Board Assembly & PCB Design SMT Electronics Assembly Manufacturing Forum

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Urgent !! Need to set up incoming boards cleanliness spec

Bernardo Mendoza

#13900

Urgent !! Need to set up incoming boards cleanliness spec | 8 October, 1998

I need to set a cleanliness limit for our incoming boards. I know that some people use 14-10 microgr. sq. in. But how can I determine what is best for me. Can anybody tell me if there's a standard for this. Right now we are using an Alpha Ionograph but since our boards are coated with a rosin we are getting very high readings. Any ideas on how to set a cleanliness limit for these boards ??? Please Help

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Chrys

#13901

Re: Urgent !! Need to set up incoming boards cleanliness spec | 9 October, 1998

| I need to set a cleanliness limit for our incoming boards. I know that some people use 14-10 microgr. sq. in. But how can I determine what is best for me. | Can anybody tell me if there's a standard for this. | Right now we are using an Alpha Ionograph but since our boards are coated with a rosin we are getting very high readings. Any ideas on how to set a cleanliness limit for these boards ??? | Please Help |

Bernardo,

I have some literature from Alpha that references 5ug/in2 max as a common specification.

Chrys

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kallol Chakraborty

#13902

Re: Urgent !! Need to set up incoming boards cleanliness spec | 9 October, 1998

| | I need to set a cleanliness limit for our incoming boards. I know that some people use 14-10 microgr. sq. in. But how can I determine what is best for me. | | Can anybody tell me if there's a standard for this. | | Right now we are using an Alpha Ionograph but since our boards are coated with a rosin we are getting very high readings. Any ideas on how to set a cleanliness limit for these boards ??? | | Please Help | | Hi there ,

| Bernardo, | | I have some literature from Alpha that references 5ug/in2 max as a common specification. | | Chrys | |

I think we have a limit of 14 ugm/sq.in for MIL which is an aggressive plan for incomming -but we do launch an investigation if we find 7 ugm/sq.in in process after oxide process or before packing(PWB manufacturing).. Please look in Mil specs for rigid (MIL 50110)/ rigid flex (MIL- 50884) acceptance criteria and IPC . Hope that helps. Kc.

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