LSF0102: LSF0102DQER

ALEX KIEVSKY

Part Number: LSF0102

Hello,

I used LSF0102DQER – 2 channels Auto-Bidirectional Multi-Voltage Level Translator for Open-Drain and Push-Pull Applications with DQE package.

We have some problems with the assembly of this component on the PCB.

The PCB manufacturer omit the solder mask between the pads according to note D in page 29 in the data sheet (attached).

According to the assembly factory the lack of solder between the pads cause shorts between the component legs, Because the lack of solder we have to assemble the component in rework machine.

The stencil thickness is 3.5 mils.

We would like to know if TI have experience with soldering this component without solder between the pad? Can TI ensure that it’s possible to solder this component without solder between the pads?

Tank's

Alex Kievsky

over 3 years ago

0 Clemens Ladisch over 3 years ago

Guru 243220 points

Without solder mask, preventing solder bridges over a 50 µm gap is basically impossible in any reasonable automated process.

Try solder mask defined pads (if 0.05 mm copper pad clearance is possible), or use a different PCB manufacturer.

0 Emrys Maier over 3 years ago

TI__Guru* 96591 points

Hi Alex,

It seems that this is the old version of our DQE package drawing - a system error has led to the wrong one being attached to the datasheet. I am currently working with our internal packaging team to get this corrected.

In the meantime, the new recommendation is to use PCB land pad width of 0.175mm, which provides solder mask width of 0.075mm and is within most PCB fab house capabilities.