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Current measuring with DRV amplifiers

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PXSS
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Current measuring with DRV amplifiers

Why does the VESC not use the current shunt amplifiers built into the DRV chip instead of adding amplifiers to the system? I see that this used to be the way it was done in 4.12hw. Why did it change for vesc6 other than to use a third current shunt? Could DRV8323R be used with the same results in a footprint?

Thanks

benjamin
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In addition to having the extra shunt, the AD8418 also are on the motor phases instead of the low side. This means that current samples can be takes twice as often compared to low side shunts, which is good for high motor speeds.

cromoly
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So is it possible to use internal amps of DRV8323 or DRV8305 instead of AD8418?

lizardmech
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You can use the newer DRV chips with three shunts if you build a custom PCB, performance would be worse, the only advantage is reduced cost and footprint.

cromoly
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How would it affect performance, in what sense? 

lizardmech
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You can only use the DRV to sense low side currents not in phase like the VESC 6. The analogue devices ones probably outperform them in every spec as well.