TXB0101:負荷側の制限

ssatake

Part Number: TXB0101
Other Parts Discussed in Thread: TXU0101, SN74LXC1T45

VCCA=3.3V, VCCB=5V, OE=3.3V. A 50kΩ pull-down resistor is connected to A of TXB0101. 3.3V system is connected to CPU. The speed is 100kHz. It will not work if connected to a 5V circuit. (Works even if the 5V circuit is not connected). What could be the possible causes?

over 2 years ago

0 Clemens Ladisch over 2 years ago

Guru 318050 points

Are there any long traces, cables, or connectors?

What exactly does "not work" mean? What are the input and output waveforms?

0 ssatake over 2 years ago in reply to Clemens Ladisch

Prodigy 40 points

コネクタが付属しています。ケーブル長は約2〜3mです。波形速度は1kHzです(100kHzは間違っています)。プルダウン抵抗を取り外しました。Aを3.3Vにすると発振するようです。AとBはどちらも約6Vp-pです。解決策はありますか?

0 Clemens Ladisch over 2 years ago in reply to ssatake

Guru 318050 points

The TXB does not work with such long cables. (The edge accelerators are not able to overcome the capacitive and inductive load, and any ringing can cause oscillations.)

What protocol are you using? For a unidirectional signal, the TXU0101 would work.

+1 ssatake over 2 years ago in reply to Clemens Ladisch

Prodigy 40 points

TXU0101は固定方向です。双方向コンポーネントはありますか?プロトコルは SDI12 です。

+1 Clemens Ladisch over 2 years ago in reply to ssatake

Guru 318050 points

It is not possible to use an auto-bidirectional translator for SDI12.

You need a direction-controlled translator like the SN74LXC1T45.

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TXB0101:負荷側の制限