buenos
Advanced Member level 3
- Joined
- Oct 24, 2005
- Messages
- 962
- Helped
- 40
- Reputation
- 82
- Reaction score
- 24
- Trophy points
- 1,298
- Location
- Florida, USA
- Activity points
- 9,143
Have you seen a QFN footprint with absolutely zero soldermask under the qfn package? The package body is a massive rectangle opening on the soldermask layer.
Someone was showing me this, and the purpose was to allow flux to exit from under the center pad.
But with no soldermask coverage, adjacent pins that are on the same net (like many dcdc converters), would short, so to solve this artificial problem they only connect the pins to a common power shape outside of the package (no flooding), that creates a third problem with power integrity.
Someone was showing me this, and the purpose was to allow flux to exit from under the center pad.
But with no soldermask coverage, adjacent pins that are on the same net (like many dcdc converters), would short, so to solve this artificial problem they only connect the pins to a common power shape outside of the package (no flooding), that creates a third problem with power integrity.