TXB0102: Level Translation for MDC,MDIO, Ethernet MDC,MDIO

Rajeshnag Nagaraj

Part Number: TXB0102
Other Parts Discussed in Thread: TXS0102

Hi,

We Have used TXB0102DCUR for Level Translation for MDC/MDIO for Ethernet Interface, from 1.8V (VCCA) to 3.3V (VCCB).

attaching schematic for reference. We have tried adding 100k Pull-up on side and not having Pull-up both side but not working.

Datasheet says for open drain TXS series is recommended, but is there any way we can do work aroud for the TXB part itself for MDIO signal?

Regards

Rajesh

0 Clemens Ladisch 6 months ago

Guru 260450 points

No. The TXB is not compatible with MDC/MDIO signals; see sections 7.3.2/3/5 of the datasheet.

0 Rajeshnag Nagaraj 6 months ago in reply to Clemens Ladisch

Hi Clemens,

Can more than 50K pull up as mentioned in the Datasheet Help by any chance?

we tried 100k, 200k 56k, The Signal initially will be at 1.8V and go to low as soon as SoC starts its communication.

Regards

Rajesh

0 Clemens Ladisch 6 months ago in reply to Rajeshnag Nagaraj

Guru 260450 points

No; the TXB does not have enough drive strength to pull the MDIO signal high.

0 Rajeshnag Nagaraj 6 months ago in reply to Clemens Ladisch

Can this be addressed by replacing TXB with TXS? Do we need to give External Pull-up for MDIO with TXS?

Regards

Rajesh

0 Michael Ikwuyum 6 months ago in reply to Rajeshnag Nagaraj

HI Rajesh,

Yes, TXS is compatible with open-drain signals.

Please see TXS0102, thanks.

Best Regards,

Michael.

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