STM32L412 : Could we used the SPI interface control the 5V LED Driver IC.

[HungKai.Chien]

Could we used the SPI interface control the 5V LED Driver IC?

1. STM32L412's VCC is 3.3V, SPI's pins are FT_f type.
2. LED Driver IC's VCC is 5V.

Is there anything that needs extra attention?

Will there be problems with SPI operation?

[TDK · Accepted solution]

It should work, provided pins are correctly configured.

You need to ensure +5V is never applied when the chip is not powered (VDD=0).

What LED driver? Make sure that 3.3V is guaranteed to be logic high.

[HungKai.Chien]

Hi TDK,

Thanks a lot.

The LED Driver is IS31FL3743B.

The Vih min is 2.4V.​

[HungKai.Chien]

Hi TDK,

About this question, does ST have any document for SPI operation @ 5V?

[TDK]

I don't think you'll find anything that specific. What are you looking to find out? The reference manual is typically the best source of information, followed by the datasheet for chip-specific things.

The SPI would be operating at the STM32's voltage, which is (typically) 3.3V. Only the MISO line would be 5V.