LSF0204: LSF0204 offset

venkatesh ponduri

Part Number: LSF0204
Other Parts Discussed in Thread: TXU0304, TXU0104, TXU0204, TLV3501

Hi Team, I am using LSF0204 and circuit is . I am getting output with offset of 2.2V. May I know the reason and which pull up resistors needs to tune. Input of LSF0204 is given through res divider circuit. Is it causing this offset. Need your urgent support

THanks,

Venkatesh

over 1 year ago

0 venkatesh ponduri over 1 year ago

Prodigy 60 points

10MHz is input to LSF0204. I observed offset at input If I connect res divider to LSF. this is for your information

0 Clemens Ladisch over 1 year ago

Guru 316690 points

The LSF is a passive switch. The pull-up resistor at the output will load the resistor divider.

What are the directions of the four signals at the LSF? If none of them are bidirectional, use a unidirectional translator like the TXU0104/TXU0204/TXU0304.

0 venkatesh ponduri over 1 year ago in reply to Clemens Ladisch

Prodigy 60 points

Hi Ladish, Thanks for response. If you see comparator (TLV3501), Mux/Demux(ts5a3357dcur), LSF0204 are TI parts only. Divider main intention is to divide 3.3V to 1.8V. We want to go a head with LSF0204 as we have procured some large volume. Can you suggest what resistors I can use for divider and pull up value. Consider load can sync 10mA

0 Clemens Ladisch over 1 year ago in reply to venkatesh ponduri

Guru 316690 points

To avoid the pull-up affecting the divider, the pull-up must be much weaker than the divider resistors. This is probably not possible if you want to achieve 10 MHz.

0 Jack Guan over 1 year ago

TI__Mastermind 40206 points

Hey Venkatesh,

Adding onto Clemens response, you may reference the below equations to estimate max achievable data rate based on the current sinking capability of your board:

Regards,

Jack

0 venkatesh ponduri over 1 year ago in reply to Clemens Ladisch

Prodigy 60 points

ok. Will TXU0304/TXU0104 works with divider circuit given above. Means I will replace LSF0204 with TXU0304 and then rest all circuit will be same. Will it give proper level 1.8V to 3.3V translation

0 Clemens Ladisch over 1 year ago in reply to venkatesh ponduri

Guru 316690 points

Yes. The TXU has high-impedance inputs (so the divider voltage will not change) and buffered outputs (so it will drive the line to either 0 V or V_CCx).

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LSF0204: LSF0204 offset