TXB0104: High Current Draw

Ray Vincent Aranzaso

Part Number: TXB0104
Other Parts Discussed in Thread: TXU0304, TXU0104, TXU0204

Hi,

Good Day. I have a customer who is working with TXB0104. Please see below his query for your reference. Thank you very much.

I have used TXB0104RUTR on a previous design and didn't have as high of a current draw from the part that I'm seeing on a new design I have. I am seeing that when the translator is enabled and no voltage is applied to any inputs, the current draw is around 250uA when I was seeing almost no current draw before. When I ground the OE signal, the 250uA goes away so I get the feeling it's coming from the part.

Any idea how this could happen? Did anything change with the design recently making it so I don't see this on older boards I have with this part?

The IC consumes about 250uA when VCCB has a higher voltage than VCCA

I have 1.8v on VCCB and 3.3v on VCCA only on one of the translator chips I'm using. The other translator chips have the higher voltage on VCCB and don't have a high current draw.

Best Regards,

Ray Vincent

over 3 years ago

0 Dylan Hubbard over 3 years ago

TI__Mastermind 46195 points

Hey Ray,

Can you provide a schematic? Nothing has changed with the design of this device.

Secondly are you also stating that they aren't following this requirement:

0 Clemens Ladisch over 3 years ago

Guru 317480 points

Section 1.1 of the Biasing Requirements for TXS, TXB, and LSF Auto-Bidirectional Translators application report says:

TXS and TXB-type translators require that V_CCA is less than or equal to V_CCB. This is due to an internal protection diode that can become forward biased when the voltage on V_CCA exceeds the voltage on V_CCB. When this occurs, large amounts of current flows through V_CCA and into the diode, increasing power consumption and potentially damaging the device

It might be possible to replace the TXB with the TXU0104/TXU0204/TXU0304.

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TXB0104: High Current Draw