TMCM-1630 Hardware Manual (Rev. 1.03 / 2012-JUL-03)

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8.1.3 hallFX™ - hall sensor feedback

hallFX™ provides emulated hall sensor signals. The emulated hall sensor signals are available without a

phase shift and there is no error-prone PLL necessary, like with many other systems, nor is the knowledge

of special motor parameters required. Since it is based on the motors’ back-EMF, a minimum motor velocity

is required to get a valid signal. Therefore, the motor needs to be started without feedback, until the

velocity is high enough to generate a reliable hallFX™ signal.

Please refer to the TMCM-1630 Firmware Manual for further information about using hallFX™.

Figure 8.2: hallFX™ block diagram and timing

A switched capacitor filter for each coil supplies the measured effective coil voltages. Its filter frequency can

be adapted to the chopper frequency and the desired maximum motor velocity. An induction pulse

suppressor unit gates the commutation spikes which result from the inductive behavior of the motor coils

after switching off the current. The gating time can be adapted by an external capacitor to fit the motor

inductivity and its (maximum) velocity.

Low pass LPU

Low pass LPV

Low pass LPW

PSG

E1

E3

E2

Position signal

generation (PSG)

Induction pulse

supressor (IPS)

IPS

E1

E2

E3

U

V

W

H1

H2

H3

D

BM1

H1

D

H2

D

H3

BM2

BM3

A

SP_SUP

30k

A

30k

A

30k

A

D

Switch Cap filters

ENRS_TEST