AM6442: CLKOUT0 EXT_REFCLK1

Jithesh Balan

Part Number: AM6442
Other Parts Discussed in Thread: SK-AM64B

Tool/software:

Hi Team,

In AM6442, EXT_REFCLK1 (A19) pin is optional?. can we left it as floating? In starter kit, its directly connected to the output of clock oscillator. and the same oscillator output is connected to the main soc clock through a buffer. In my custom board design , i have connected these two soc clock inputs from a dual output clock buffer. Please let me know my design is ok or not. I am attaching the screenshot of custom board schematics.

10 months ago

0 Kallikuppa Sreenivasa 10 months ago

TI__Guru**** 193139 points

Hello Jitesh balan,

Thank you for the query.

EXT_REFCLK1 is GPIO1_69 7 IO pad during reset.

If there are no traces connected, you can leave the pin open.

if a trace is connected to the PAD, add external pull.

Assuming U58 is the buffer implementation, i do not understand the need for connecting the SOC_CLKIN and the EXT_REFCLK with the same frequency.

Delete C36 and R50. This is not required and could cause stubs on the clock signal.

Regards,

Sreenivasa

0 Jithesh Balan 10 months ago in reply to Kallikuppa Sreenivasa

Intellectual 440 points

Hi Sreeni

Thanks for the quick reply, iam attaching the screenshot of starter kit (SK-AM64B) schematics, in that schematics EXT_REFCLK pin is fed from oscillator, thats what i confused. whether the clock signal to that soc pin is really required or not.

Also c36 and R50 is provided as an option in Both evk and starter kit. Anyway this we can remove.