LMK03318: Question on how to program LMK03318

ST LOH

Part Number: LMK03318

Hi, i need to program the LMK03318 to be able to generate a 100Mhz, and 156.25mHz LVDS clock output. Can u let me know what the settings should be for the LMK03318 IC ? I check on the ROM Content (GPIO[5:0] = 24 , 011000, may be able to support to generate the 100Mhz and 156.25Mhz clock frequencies.

However, i not sure what other pins setting/connections should be connected, (pullup/down, no connect or gnd).

Attached the schematics that drafted based on my understanding from LMK03318 documents. Pls review.

rdgs

stloh

over 2 years ago

0 Kadeem Samuel over 2 years ago

TI__Mastermind 22210 points

Stloh,

If you are using the ROM mode, then you need GPIO[5:0] = 24d = 0b011000, or the following:

GPIO5 = Low
GPIO4 = High
GPIO3 = High
GPIO2 = Low
GPIO1 = Low
GPIO0 = Low
HW_SW_CTRL = High
REFSEL = 0.9V (Input mid voltage for the 3-level logic, this selects the secondary clock as the PLL preference)

Thanks,

Kadeem

0 ST LOH over 2 years ago in reply to Kadeem Samuel

Prodigy 50 points

Tx Kadeem. How about the PDN pin ? What is yr recommendation to connect ? Direct to GND with cap (as recommended in datasheet) ? Or PDN - NC, internally already pullup to high ?

rdgs

stloh

0 Kadeem Samuel over 2 years ago in reply to ST LOH

TI__Mastermind 22210 points

Stloh,

Please follow the datasheet recommendation of connecting a capacitor between the PDN pin and GND. Alternatively, a jumper can be added to allow for a connection between the pin and GND, similar to what the EVM does with the button for PDN.

Thanks,

Kadeem

+1 ST LOH over 2 years ago in reply to Kadeem Samuel

Prodigy 50 points

Thx for the info Kadeem. That helps alot.

0 Kadeem Samuel over 2 years ago in reply to ST LOH

TI__Mastermind 22210 points

Stloh,

Of course. Please let me know if you have any further questions.

Thanks,

Kadeem

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LMK03318: Question on how to program LMK03318