Datasheet
Table Of Contents
- Table 1. Device summary
- 1 Block diagram
- 2 Electrical data
- 3 Electrical characteristics
- 4 Pin connection
- 5 Typical applications
- 6 Functional description
- 6.1 Device power-up
- 6.2 Logic I/O
- 6.3 Charge pump
- 6.4 Microstepping
- 6.5 Absolute position counter
- 6.6 Programmable speed profiles
- 6.7 Motor control commands
- 6.8 Internal oscillator and oscillator driver
- 6.9 Overcurrent detection
- 6.10 Undervoltage lockout (UVLO)
- 6.11 Thermal warning and thermal shutdown
- 6.12 Reset and standby
- 6.13 External switch (SW pin)
- 6.14 Programmable DMOS slew rate, deadtime and blanking time
- 6.15 Integrated analog-to-digital converter
- 6.16 Internal voltage regulator
- 6.17 BUSY\SYNC pin
- 6.18 FLAG pin
- 7 Phase current control
- 8 Serial interface
- 9 Programming manual
- 9.1 Registers and flags description
- Table 9. Register map
- 9.1.1 ABS_POS
- 9.1.2 EL_POS
- 9.1.3 MARK
- 9.1.4 SPEED
- 9.1.5 ACC
- 9.1.6 DEC
- 9.1.7 MAX_SPEED
- 9.1.8 MIN_SPEED
- 9.1.9 FS_SPD
- 9.1.10 KVAL_HOLD, KVAL_RUN, KVAL_ACC and KVAL_DEC
- 9.1.11 INT_SPEED
- 9.1.12 ST_SLP
- 9.1.13 FN_SLP_ACC
- 9.1.14 FN_SLP_DEC
- 9.1.15 K_THERM
- 9.1.16 ADC_OUT
- 9.1.17 OCD_TH
- 9.1.18 STALL_TH
- 9.1.19 STEP_MODE
- 9.1.20 ALARM_EN
- 9.1.21 CONFIG
- Table 22. CONFIG register
- Table 23. Oscillator management
- Table 24. External switch hard stop interrupt mode
- Table 25. Overcurrent event
- Table 26. Programmable power bridge output slew rate values
- Table 27. Motor supply voltage compensation enable
- Table 28. PWM frequency: integer division factor
- Table 29. PWM frequency: multiplication factor
- Table 30. Available PWM frequencies [kHz]: 8-MHz oscillator frequency
- Table 31. Available PWM frequencies [kHz]: 16-MHz oscillator frequency
- Table 32. Available PWM frequencies [kHz]: 24-MHz oscillator frequency
- Table 33. Available PWM frequencies [kHz]: 32-MHz oscillator frequency
- 9.1.22 STATUS
- 9.2 Application commands
- Table 37. Application commands
- 9.2.1 Command management
- 9.2.2 Nop
- 9.2.3 SetParam (PARAM, VALUE)
- 9.2.4 GetParam (PARAM)
- 9.2.5 Run (DIR, SPD)
- 9.2.6 StepClock (DIR)
- 9.2.7 Move (DIR, N_STEP)
- 9.2.8 GoTo (ABS_POS)
- 9.2.9 GoTo_DIR (DIR, ABS_POS)
- 9.2.10 GoUntil (ACT, DIR, SPD)
- 9.2.11 ReleaseSW (ACT, DIR)
- 9.2.12 GoHome
- 9.2.13 GoMark
- 9.2.14 ResetPos
- 9.2.15 ResetDevice
- 9.2.16 SoftStop
- 9.2.17 HardStop
- 9.2.18 SoftHiZ
- 9.2.19 HardHiZ
- 9.2.20 GetStatus
- 9.1 Registers and flags description
- 10 Package mechanical data
- 11 Revision history
L6470 Phase current control
Doc ID16737 Rev 5 35/70
7.2 Sensorless stall detection
Depending on motor speed and load angle characteristics, the L6470 offers a motor stall
condition detection using a programmable current comparator.
When a stall event occurs, the respective flag (STEP_LOSS_A or STEP_LOSS_B) is forced
low until a GetStaus command or a system reset occurs (see Section 9.2.20).
7.3 Low speed optimization
When the motor is driven at a very low speed using a small driving voltage, the resulting
phase current can be distorted. As a consequence, the motor position is different from the
ideal one (see Figure 15).
The L6470 implements a low speed optimization in order to remove this effect.
Figure 15. Current distortion and compensation
The optimization can be enabled setting high the LSPD_OPT bit in the MIN_SPEED register
(see Section 9.1.8) and is active in a speed range from zero to MIN_SPEED. When low
speed optimization is enabled, speed profile minimum speed is forced to zero.
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PHASE
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PHASE
#URRENTDISTORTIONISHEAVILY
REDUCED
7ITHOUTLOWSPEEDOPTIMIZAZION
7ITHLOWSPEEDOPTIMIZAZION
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