LMK04828: LMK04828 1.8V IO support

Yarn Guo

Part Number: LMK04828

Hi, Experts:

We are trying to interface with LMK04828 with 1.8V IO due to the limited resource of 3.3V IO in FPGA.

For the digital input signal of LMK, I think we need to make sure the MIN number of VOH of FPGA >1.2V and MAX number of VOL< 0.4V.

For the digital output signal of LMK, I can use a resistor divider like 10K series resistor and 12K shunt resistor to divide the 3.3V IO down to 1.8V.

Can you please help to double check if you see any issues regarding this?

Thanks a ton for your kind help

Yarn.

over 7 years ago

0 Shawn Han over 7 years ago

TI__Genius 9920 points

Hi Yarn,
You are right. SPI have to use 4 wire mode.
They could work. Please double check FPGA spec.

Regards,
Shawn

0 Yarn Guo over 7 years ago in reply to Shawn Han

TI__Intellectual 1440 points

Hi, Shawn:

Thank you so much for your prompt reply.

I will suggest customer to use RESET/GPO or CLKin_SELX to serve as SDO. Thank you.
Yarn

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LMK04828: LMK04828 1.8V IO support