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8-Channel Logic Level Shifter and Lora

Hi all,
I’m trying to interface a 8-Channel Logic Level Shifter TXB0108 with Lora sx1276 without success. I’m trying to reduce the voltage of power source 5V or 4.2V to 3.3V.
Do anyone have a tutorial somewhere?
Is it compatible?

The first question, is does your micro need level Translation? Does it have TTL compatible inputs?

The TB0188 relies on sensing the direction of the signal, so it can be confused if the levels are static.

An alternative, Consider HCT logic from 3.3V to 5V You will have a current premium to pay, since the input isn’t 0V or 5V but HCT has a lower threshold, 2V, so will always transition. For the other direction… LVC Logic has 5V tolerant inputs, 3.3V outputs.

Also consider things like SN74AVC4T245, 2 x dual buffer, dual power supply direction is by pin rather than internal logic.

Simon

Uhmm, a lot of information, let met take a look.
My MCU is Atmega328p/ATtiny84.
Thanks.