AWR1243: Does AWR1243 support external clock source input instead of crystal?

Chris Meng

Part Number: AWR1243
Other Parts Discussed in Thread: AWR1443,

Hi,

In AWR1443 datasheet, it only mentioned crystal use case. Does it also support external clock source input?

My customer's board is not stable and sometimes the crystal can't work with internal oscillator which causes not clock generated. So they want to know if AWR1243 also supports external clock input so they can try that way to see if the board can work stable.

Thanks,

over 6 years ago

0 Vivek Dham over 6 years ago

TI__Guru 58035 points

Hello Chris,
We do support external clock option for the 40Mhz reference clock. The clock needs to be a sin wave clock with amplitude 700-1200 mVpp and needs to the fed on the XTALP pin. The XTALM pin needs to be pulled to GND for this mode of operation.

Regards,
Vivek

0 Chris Meng over 6 years ago in reply to Vivek Dham

TI__Mastermind 35185 points

Vivek,

Thanks for your reply. What is the voltage of the external clock signal? 1.8V or 1.2V Vpeak?

0 Vivek Dham over 6 years ago in reply to Chris Meng

TI__Guru 58035 points

Hello Chris,
As mentioned above the clock amplitude should be within 700 - 1200 mVpp.

regards,
Vivek

0 Chris Meng over 6 years ago in reply to Vivek Dham

TI__Mastermind 35185 points

Vivek,

Is it ok to use square wave clock?

Thanks,

0 Vivek Dham over 6 years ago in reply to Chris Meng

TI__Guru 58035 points

Hello Chris,
Yes even square wave clock can be used, in that case it has to be a 1.8V level square wave input.

Regards,
Vivek

0 Chris Meng over 6 years ago in reply to Vivek Dham

TI__Mastermind 35185 points

Vivek,

In AWR1243 data sheet, I found below info in the first page. Why 50Mhz crystal is not mentioned? Will the info be updated in later datasheet?

• Clock Source
– 40.0-MHz Crystal With Internal Oscillator
– Supports External Oscillator at 40 and 50 MHz

0 Vivek Dham over 6 years ago in reply to Chris Meng

TI__Guru 58035 points

Hello Chris,
50 Mhz is supported even with internal oscillator mode. We will update the datasheet with this info.

Regards,
Vivek

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AWR1243: Does AWR1243 support external clock source input instead of crystal?