TXB0304: Using TXB0304 with FT2232H for UART level translation

Muthu Shankar

Part Number: TXB0304
Other Parts Discussed in Thread: SN74AXC4T245

Hello,

I am seeing that I can use TXB0304 with FT2232H for UART level translation. What I have found is that TXB0304's drive strength is 20uA and FT2232H's input pin leakage current is 45uA . Does it mean that I can not use TXB0304 since its 20uA drive strength is not enough to drive 45uA input pin as a load ?. Please suggest and correct me if I am wrong.

TXB0304:

FT2232H:

Thanks and Regards,

Muthu

over 5 years ago

0 ShreyasRao over 5 years ago

TI__Guru 62350 points

Hi Muthu,

you could consider using the buffered level translator SN74AXC4T245 for high drive UART interface applications.

TXB0304 doesnt provide high DC current drive, however, due to the internal oneshots present it can overcome the leakage current of the receivers input pins.

the host / driver to the TXB0304 must have high enough drive strength ( 3mA) to change the state of the line.

0 ShreyasRao over 5 years ago in reply to ShreyasRao

TI__Guru 62350 points

Read the app note:

Also, please watch the UART level translation video.

Hope this helps.

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TXB0304: Using TXB0304 with FT2232H for UART level translation