EVM430-FR6043: Is it possible to use the analog front-end for water flow measurements @2MHz ?

Recep Polat

Part Number: EVM430-FR6043
Other Parts Discussed in Thread: TIDM-02005, MSP430FR6043

Greetings,

we opted for this board instead of the 6047 due to the on-board amplification possibility. Therefore, I don't want to cancel the AFE as suggested by TIDM-02005 (if I understand correctly).

Is there a way to modify the PCB to use the AFE at 2MHz for example, for water flow measurements?

Thanks in advance!

over 1 year ago

0 Dennis Lehman over 1 year ago

TI__Guru 60041 points

Hi Recep,

Yes, see section 3 in the Optimized Ultrasonic Sensing Metrology reference guide for water flow measurements.

0 Recep Polat over 1 year ago in reply to Dennis Lehman

Prodigy 30 points

I'm guessing this procedure is what you mean.

Well, the 3rd entry means cutting power off the whole analog front end. This isn't what I want.

Or am I mistaken?

+1 Seth Jackson over 1 year ago in reply to Recep Polat

Expert 1780 points

The analog front end is required amplification when making gas flow measurements at a few hundred kilohertz. For water flow measurements, extra amplification isn't typically necessary; the PGA within the MSP430FR6043 is sufficient so the analog front end on the EVM is bypassed in most use cases.

The problem you'll find is that there is low pass filtering and impedance matching on the AFE for gas transducers. You'll need to modify the feedback components around U10 and change values at the filter between U8 and U9 on the schematic.

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EVM430-FR6043: Is it possible to use the analog front-end for water flow measurements @2MHz ?