LMP92066: Clock frequency during operation, as part of lookup process

Christopher Monroy

Part Number: LMP92066

Hello, I am currently using the LMP92066 in my design, and wanted to know what the clock rate during operation is. In other words, when the device powers up, reads the temperature and sets a voltage in the DAC is there an internal clock driving the device? Is this what's referred to in the datasheet as "Conversion time"? I am making sure any spurious signals in my module can be filtered, so accounting for any clock signals is important

over 2 years ago

0 Paul_Frost over 2 years ago

TI__Guru 53573 points

Hi Christopher,

This sample rate is the conversion time. There is a faster clock in the system, but the sample rate is a division of that, as the LMP requires a certain number clocks to to complete the sampling and conversion. I recommend a low-pass filter of <50% the sample rate.

Thanks,

Paul

0 Christopher Monroy over 2 years ago in reply to Paul_Frost

Prodigy 100 points

Thanks Paul, as a follow up can you tell me the rate of the faster clock?

0 Paul_Frost over 2 years ago in reply to Christopher Monroy

TI__Guru 53573 points

I believe it is ~1MHz.

0 Christopher Monroy over 2 years ago in reply to Paul_Frost

Prodigy 100 points

Thanks Paul, would the conversion time also apply to the startup time? In other words, when all power supplies are provided to the device, how long does it take to set the DAC voltage? Is that related to the 25 mS?

0 Joseph Wu over 2 years ago in reply to Christopher Monroy

TI__Guru* 94305 points

Christopher,

Paul will get back to you as soon as possible, but it's likely that he won't be able to get an answer to you until Monday.

Joseph Wu

0 Paul_Frost over 2 years ago in reply to Joseph Wu

TI__Guru 53573 points

Hi Christopher,

The 25ms sample times dominates the startup time as well. Figure 50 shows the startup time as approximately ~26ms. The device needs some time to initialize its EEPROM.

Thanks,

Paul

0 Christopher Monroy over 2 years ago in reply to Paul_Frost

Prodigy 100 points

Thank you Paul

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LMP92066: Clock frequency during operation, as part of lookup process