SPI not work with voltage logic shifter

[Govind89]

We are using the iW-RainboW-G50S i.MX 93 or i.MX 91 Pico ITX Single Board Computer. On this board, we want to use SPI4, but it has an onboard SPI Flash "IS25WP016D-JNLE" operating at a 1.8V level. We removed this IC, soldered wires to break out the connection, and tested an external SPI slave operating at 1.8V, which worked fine. Now, our slave device has changed and operates at 3.3V. To accommodate this, we are using the TXB0104 4-Bit Bidirectional Voltage-Level Translator with automatic direction sensing. However, we are unable to detect proper signals.

[pengyong_zhang]

hi @Govind89 

Here are some suggestions for your issue:

1.  Check the data sheet of the level converter to ensure that it is used and connected correctly.
2. Use an oscilloscope to observe the signal waveform of the SPI interface and confirm whether the signal is correctly converted.
3. Try to replace the level converter and troubleshoot the device.
4. Carefully review the SPI communication code to ensure that the code logic is correct.

And could you please share your PCB schematic file?

B.R