L6470HTR STMicroelectronics, L6470HTR Datasheet - Page 32

• Manufacturer Part Number: L6470HTR
• Description: IC STEPPER/DC MOTOR DVR 28HTSSOP
• Manufacturer: STMicroelectronics

Specifications of L6470HTR

• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 497-10812-2

Phase current control
7.4
7.5
32/64
BEMF compensation
Using the speed information, a compensation curve is added to the amplitude of the voltage
waveform applied to the motor winding in order to compensate the BEMF variations during
acceleration and deceleration (see
Compensation curve is approximated by a stacked line with a starting slope (ST_SLP) when
speed is lower than a programmable threshold speed (INT_SPEED) and a fine slope
(FN_SLP_ACC and FN_SLP_DEC) when speed is greater than the threshold speed (see
paragraphs
To obtain different current values during acceleration and deceleration phase two different
final slope values, and consequently two different compensation curves, can be
programmed.
Acceleration compensation curve is applied when the motor runs. No BEMF compensation
is applied when the motor is stopped.
Motor supply voltage compensation
The sinewave amplitude generated by the PWM modulators is directly proportional to the
motor supply voltage (V
the motor phases are driven with an incorrect voltage. The L6470 can compensate motor
supply voltage variations in order to avoid this effect.
The motor supply voltage should be connected to the integrated ADC input through a
resistor divider in order to obtain V
value (see
The ADC input is sampled at f
Figure 14. BEMF compensation curve
Figure 15
9.1.11
,
9.1.12
).
S
). When the motor supply voltage is different from its nominal value,
,
9.1.13
S
Doc ID 16737 Rev 2
frequency, which is equal to PWM frequency.
and
REG
Figure 14
/2 voltage at the ADCIN pin when V
9.1.14
).
).
S
is at its nominal
L6470