Using 16MHz oscillator for Msp430f1xxx

shadowfax47

Hello everyone,

The datasheets for Msp430f1xxx suggests Max operating frequency for LFXTI in HF mode (XTS=1) as 8MHz (Vcc=3.6V). But I have 16MHz oscillator I would like to use. Is it sufficient if I use the internal clock divider on the MSP to make sure the MCLK and SMCLK runs at 8MHz or should the input frequency at the XIN already be 8MHz? In other words should the clock divider come from an external circuit?

Thanks and Regards,

over 9 years ago

0 Dennis Eichmann over 9 years ago

Guru 74080 points

The datasheet says the maximum input frequency is 8MHz, so dividing the 16MHz clock before feeding it to (S)MCLK is out of specifications already.

Dennis

0 shadowfax47 over 9 years ago in reply to Dennis Eichmann

Prodigy 240 points

Thanks Dennis for your response. Yes you are right, but should it not be Ok as long as (S)MCLK is running at <= 8MHz or will this result in unexpected behavior?

0 Dennis Eichmann over 9 years ago in reply to shadowfax47

Guru 74080 points

Hard to say - if the input is not made for such high frequencies, the result might be unpredictable.

0 shadowfax47 over 9 years ago in reply to Dennis Eichmann

Prodigy 240 points

Currently, I use 16MHz oscillator and it works just fine. I wanted to know in which scenarios it will become unpredictable (if at all that is the case).

0 Dennis Eichmann over 9 years ago in reply to shadowfax47

Guru 74080 points

The device might even run at 16MHz, the only thing is the reliability because TI does not guarantee for an error free operation. If it works and it is for a hobby project, why not. But of course you shouldn't run a device out of it's specification when it is a sold unit that might be used in different environments.

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Using 16MHz oscillator for Msp430f1xxx