DRV8316 datasheet(39/97 Pages) TI

39 / 97 page

8.3.12 Current Sense Amplifier Offset Correction

CSA output has an offset induced due to ground differences between the sense FET and output FET. When

running trapezoidal control or another single-shunt based control (sensored sine, for example) this CSA offset

has no impact to operation. When running sensorless sinusoidal or FOC control where two or three current

sense are required, some current distortion and noise may occur unless the user implements the corrective

action below.

Corrective Action: Implement the below equations in firmware to correct for any current induced offset:

1. When all three current sense amplifiers are used:

ia=0.995832*ia_sensed −0.028199*ib_sensed −0.014988*ic_sensed

(5)

ib= 0.037737*iasensed +1.007723*ib_sensed −0.033757*ic_sensed

(6)

ic= 0.009226*iasensed+ 0.029805*ibsensed +1.003268*ic_sensed

(7)

2. When only two of the three current sense amplifiers are used:

a. Current sensed in phases A & B:

ia= 1.013075*ia_sensed −0.01236*ib_sensed

(8)

ia= 1.013075*ia_sensed −0.01236*ib_sensed

(9)

ic=− ia+ib

(10)

b. Current sensed in phases B & C:

ib= 0.971197*ib_sensed −0.0683*ic_sensed

(11)

ic= 0.020876*ibsensed +0.994823*ic_sensed

(12)

ia=− ib+ic

(13)

c. Current sensed in phases C & A:

ia= 1.025489*iasensed +0.011936*ic_sensed

(14)

ic= 0.022043*iasensed+0.996548*ic_sensed

(15)

ib=− ia+ic

(16)

www.ti.com

DRV8316-Q1

SLVSGK9 – JANUARY 2022

Submit Document Feedback

Product Folder Links: DRV8316-Q1

DRV8316 Datasheet(PDF) 39 Page - Texas Instruments