Other Parts Discussed in Thread: LDC3114
Hello,
I'm currently using the 1612 evm board to facilitate the design of a new inductive base sensor and I was wondering if someone could explain the LDC's driving frequency that is being applied to the sensors LC tank in order to calculate the resonance frequency shift as a ratio to the clock frequency.
In the manual there is mention that the driving frequency is from 1k to 10MHz, though I'm wondering if this is actually the case. I do not have a EE heavy background, so please feel to point out any flaws in my logic. My best guess as to how the signal is actually determined is though the comparison of the voltage drop across the LC tank vs a reference (Since there is a set, constant current, the shift in the voltage across the sensor is being driven by the change in parallel resistance as the inductor moves closer or farther away from the self resonance frequency). Is this correct? If so, I would assume that the driving frequency range is determined by some scaler of the reference clock and the achievable resolution of the voltage measurement? One of the questions I am looking to answer is, if I were to connect a sensor where the LC tank resonance is outside that driving range (with the Rp linearly increasing over the driving frequency range), would it be safe to say that the signal that the LDC is measuring is just using the L, C and Rp values at last frequency of the range, 10MHz? I feel as though this can't be exactly the case, as there are options mentioned in the manual for setting a scalor to shift the measured frequency within the driving range.
I do not have a EE heavy background, so please feel to point out any flaws in my logic! Thanks in advanced!
