Dried (aka heated reflowed deactivated and polymerized) flux is definitely an issue.
Get a corrective action on the supplier to ensure it is removed the same as any other BGA device.
Sent from my iPad Pro
On Fri, Aug 25, 2017 at 2:12 AM +0800, "Steven Kelly" <[log in to unmask]> wrote:
Hi All,
I have a new hi-density BGA connector I am trying to assemble. When the supplier makes the connector they "solder balls onto the pin" (lead free). We see dried flux on the balls and when we solder the connector we are getting a few joints with head in pillow. The connector manufacturer says the dried flux is not an issue - is this true? Thanks. Steve Kelly