TXS0104E: Alternate part for TXS0104EPWR

Nireeksha Shetty

Part Number: TXS0104E

Hi,

Currently we are using TXS0104EPWR (4-BIT) part in our design for converting voltage level from 1V8 to 3V3.We are using this for MDIO and MDC pin of Ethernet PHY.

With this part we are facing IO level mismatch between CPU pins and Level Translator pins.

Could you please suggest a 4-bit translator part which supports MDC and MDIO pin ( Open-drain).Also the translator should have VIH > 1.35 AND VIL > 0.45.

Attached the block diagram of the same.

Regards,

Nireeksha

over 3 years ago

0 Clemens Ladisch over 3 years ago

Guru 317250 points

What are the supply voltages of these devices? Are there any pull-up or pull-down resistors?

0 Nireeksha Shetty over 3 years ago

Prodigy 180 points

1. VCCA - 1.8V and VCCB- 3.3V

2. There are no pull-up and pull-down resistors.

0 Clemens Ladisch over 3 years ago in reply to Nireeksha Shetty

Guru 317250 points

What are the test currents for these V_OH/V_OL values? The actual currents are likely to be lower, so the TXS0104E is likely to work.

0 Nireeksha Shetty over 3 years ago in reply to Clemens Ladisch

Prodigy 180 points

Yes this works. But since there is an IO level mismatch between the CPU and level translator we are planning to choose a level translator which matches with the IO level.

Apologies, there is a correction:

VIH of level translator should be less than 1.35

VIL of level translator should be greater than 0.45

Attached corrected Block diagram

0 Clemens Ladisch over 3 years ago in reply to Nireeksha Shetty

Guru 317250 points

The total current through the internal pull-up resistors of the TXS is about 0.5 mA, so the V_OH/V_OL values you have shown will not actually happen in this circuit. Please specify what CPU you are using.

0 Nireeksha Shetty over 3 years ago in reply to Clemens Ladisch

Prodigy 180 points

I'm using SoC - xczu19eg-ffvc1760 (Xilinx).

This totally works fine,but due to IO level mis-match we are planning to change.

0 Clemens Ladisch over 3 years ago in reply to Nireeksha Shetty

Guru 317250 points

There is no mismatch. The same table that tells you V_OH/V_OL also has I_OH/I_OL columns at the right. Reducing the output current also reduces the voltage drop over the output transistors, so even with the weakest drive strength setting of 4 mA, the actual current of 0.5 mA will result in V_OL ≈ 0.1 V and V_OH ≈ V_CCO − 0.1 V.

Logic

Logic forum

TXS0104E: Alternate part for TXS0104EPWR