TXS0104E: Using TXS0104ERGYR as Level Translator for I²C Open-Drain Signals

Jefin George

Part Number: TXS0104E
Other Parts Discussed in Thread: TXB0104

Tool/software:

I would like to confirm the suitability of the TXS0104ERGYR voltage-level translator for use in an I²C application. Since I²C requires open-drain operation with external pull-up resistors, I would like to verify the following points:

Can the TXS0104ERGYR reliably handle bidirectional I²C signals (SDA and SCL) at Standard Mode (100 kHz) and Fast Mode (400 kHz)?
Are there any limitations or caveats when using this device for Fast Mode Plus (1 MHz) operation?
Does TI recommend the TXS0104E over the TXB0104 for I²C, given the open-drain requirement?
Are there specific guidelines on pull-up resistor values and bus capacitance when using TXS0104ERGYR in I²C systems?
what about TXB0104 for I²C? Why it is not prefered?

8 days ago

0 Jack Guan 7 days ago

TI__Mastermind 40206 points

Hi Jefin,

1. Yes, this device is suited for I2C signals.

2. No.

3. Yes, TXS is better suited for open drain signals. TXB is not suited for open drain signals due to its push-pull architecture/ sensitivity on use of external pullups

4. No external pullups are needed due to internal 10kohms. Bus capacitance should be kept relatively short (<70pF) for optimal SI.

5. See answer to question 3.

If driving I2C signals over long traces, TI also has I2C buffer portfolio for redriving I2C signals/ splitting bus capacitances, link here: https://www.ti.com/product-category/interface/i2c-i3c-ics/i2c-i3c-ics-level-shifters-buffers-hubs/products.html#1389=I2C&2192=Buffer&

Regards,

Jack

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TXS0104E: Using TXS0104ERGYR as Level Translator for I²C Open-Drain Signals