TXB0108: waveform of 5V level-up output

Jerry Chen

Part Number: TXB0108
Other Parts Discussed in Thread: SN74LVC8T245, SN74AHCT541

Hi there,

My customer is using TXB0108 to level-up 3.3V to 5V. And I see the output is as below figure. I think it is because the capability to drive apacitive loads is limited, so should I recommend them to switch to SN74AXC8T245 ?

Thanks.

over 5 years ago

0 Clemens Ladisch over 5 years ago

Guru 316470 points

Yes, a load that is too large looks like this.

If the signals are unidirectional, a direction-controlled translator like the SN74LVC8T245 will work much better. (AXC does not go above 3.3 V.) But for 3.3 V → 5 V translation, you could simply use a buffer with TTL-compatible inputs, such as the SN74AHCT541.

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TXB0108: waveform of 5V level-up output