Datasheet

Table Of Contents
L6470 Phase current control
Doc ID16737 Rev 5 37/70
Motor supply voltage compensation can be enabled setting high the EN_VSCOMP bit of the
CONFIG register (see Ta bl e 22 , Section 9.1.21). If the EN_VSCOMP bit is low, the
compensation is disabled and the internal analog-to-digital converter is at the user’s
disposal; sampling rate is always equal to PWM frequency.
7.6 Winding resistance thermal drift compensation
The higher the winding resistance, the greater the voltage to be applied in order to obtain
the same phase current.
The L6470 integrates a register (K_THERM) which can be used to compensate phase
resistance increment due to temperature rising.
The value in the K_THERM register (see Section 9.1.15) multiplies the duty cycle value
allowing a higher phase resistance value to be faced.
The compensation algorithm and the eventual motor temperature measurement should be
implemented by microcontroller firmware.
Figure 17. Motor supply voltage compensation circuit
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