LSF0108: LSF0108PWR issue

guru sai

Intellectual 560 points

Part Number: LSF0108

Hi team,

Please find the below schematics

We are using LSF0108PWR in our design for level translating 1.8V to 3.3V and vice versa.

ref A : we have connected 3.3V

ref B : we have connected 1.8V

While testing we have observed,

Signals from side A (3.3V signals) are converted to 1.8V at the side B.

But, Signals from side B (1.8V) are not converting to 3.3V at side A.

Please suggest the solution / any technique for working functionally with existing design as our board are fabricated.

over 4 years ago

0 Clemens Ladisch over 4 years ago

Guru 320650 points

This schematic does not show any pull-up resistors. The resistor at EN must be connected to the higher power supply, and the corresponding VREF must be connected to EN. There is no other pin-compatible level shifter. This board cannot be used.

0 Dylan Hubbard over 4 years ago in reply to Clemens Ladisch

TI__Mastermind 46735 points

Hi Guru,

As mentioned by Clemens, there is no fix to this that doesn't require a redesign. Here are training videos that cover how to properly implement the LSF device that should be of great help for future use. Videos 2 and 3 will elaborate more on what Clemens has said about the EN pin.

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LSF0108: LSF0108PWR issue