ST L6470H User manual

November 2010 Doc ID 16737 Rev 2 1/64
64
L6470
Fully integrated microstepping motor driver
with motion engine and SPI
Features
■Operating voltage: 8 - 45 V
■7.0 A output peak current (3.0 A r.m.s.)
■Low RDSon power MOSFETS
■Programmable speed profile and positioning
■Programmable power MOS slew-rate
■Up to 1/128 microstepping
■Sensorless stall detection
■SPI interface
■Low quiescent and standby currents
■Programmable non dissipative overcurrent
protection on high and low-side
■Two levels overtemperature protection
Applications
■Bipolar stepper motor
Description
The L6470, realized in analog mixed signal
technology, is an advanced fully integrated
solution suitable for driving two phase bipolar
stepper motors with microstepping.
It integrates a dual low RDSon DMOS full bridge
with all of the power switches equipped with an
accurate on chip current sensing circuitry suitable
for non dissipative current control and overcurrent
protections. Thanks to a unique control system a
true 1/128 steps resolution is achieved. The
digital control core can generate user defined
motion profiles with acceleration, deceleration,
speed or target position easily programmed
through a dedicated registers set. All commands
and data registers, including those used to set
analogue values (i.e. current control value,
current protection trip point, dead time, PWM
frequency etc.) are sent through a standard
5Mbit/s SPI.
A very rich set of protections (thermal, low bus
voltage, overcurrent, motor stall) allows designing
a fully protected application, as required by most
demanding motor control applications.
HTSSOP28
Table 1. Device summary
Order codes Package Packing
L6470H HTSSOP28 Tube
L6470HTR HTSSOP28 Tape and reel
www.st.com

Contents L6470
2/64 Doc ID 16737 Rev 2
Contents
1 Block diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
2 Electrical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
2.1 Absolute maximum ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
2.2 Recommended operating conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
3 Electrical characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
4 Pin connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
4.1 Pin list . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
5 Typical applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
6 Functional description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
6.1 Device power-up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
6.2 Logic I/O . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
6.3 Charge pump . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
6.4 Microstepping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
6.5 Absolute position counter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
6.6 Programmable speed profiles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
6.6.1 Infinite acceleration/deceleration mode . . . . . . . . . . . . . . . . . . . . . . . . . 21
6.7 Motor control commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
6.7.1 Constant speed commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
6.7.2 Positioning commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
6.7.3 Motion commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
6.7.4 Stop commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
6.7.5 Step-clock mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
6.8 Internal oscillator and oscillator driver . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
6.8.1 Internal oscillator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
6.8.2 External clock source . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
6.9 Overcurrent detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
6.10 Undervoltage lock-out (UVLO) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
6.11 Thermal warning and thermal shutdown . . . . . . . . . . . . . . . . . . . . . . . . . 26

L6470 Contents
Doc ID 16737 Rev 2 3/64
6.12 Reset and standby . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
6.13 External switch (SW pin) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
6.14 Programmable DMOS slew-rate, dead-time and blanking-time . . . . . . . . 28
6.15 Integrated analog to digital converter . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
6.16 Internal voltage regulator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
6.17 BUSY\SYNC pin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
6.17.1 BUSY operation mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
6.17.2 SYNC operation mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
6.18 FLAG pin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
7 Phase current control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
7.1 PWM sinewave generators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
7.2 Sensorless stall detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
7.3 Low speed optimization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
7.4 BEMF compensation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
7.5 Motor supply voltage compensation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
7.6 Winding resistance thermal drift compensation . . . . . . . . . . . . . . . . . . . . 33
8 Serial interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
9 Programming manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
9.1 Registers and flags description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
9.1.1 ABS_POS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
9.1.2 EL_POS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
9.1.3 MARK . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
9.1.4 SPEED . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
9.1.5 ACC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
9.1.6 DEC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
9.1.7 MAX_SPEED . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
9.1.8 MIN_SPEED . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
9.1.9 FS_SPD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
9.1.10 KVAL_HOLD, KVAL_RUN, KVAL_ACC and KVAL_DEC . . . . . . . . . . . . 40
9.1.11 INT_SPEED . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
9.1.12 ST_SLP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
9.1.13 FN_SLP_ACC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
9.1.14 FN_SLP_DEC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42

Contents L6470
4/64 Doc ID 16737 Rev 2
9.1.15 K_THERM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
9.1.16 ADC_OUT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
9.1.17 OCD_TH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
9.1.18 STALL_TH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
9.1.19 STEP_MODE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
9.1.20 ALARM_EN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
9.1.21 CONFIG . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
9.1.22 STATUS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
9.2 Application commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
9.2.1 Command management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
9.2.2 Nop . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
9.2.3 SetParam (PARAM, VALUE) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54
9.2.4 GetParam (PARAM) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54
9.2.5 Run (DIR, SPD) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
9.2.6 StepClock (DIR) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
9.2.7 Move (DIR, N_STEP) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56
9.2.8 GoTo (ABS_POS) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56
9.2.9 GoTo_DIR (DIR, ABS_POS) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
9.2.10 GoUntil (ACT, DIR, SPD) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
9.2.11 ReleaseSW (ACT, DIR) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
9.2.12 GoHome . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
9.2.13 GoMark . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
9.2.14 ResetPos . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
9.2.15 ResetDevice . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
9.2.16 SoftStop . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
9.2.17 HardStop . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
9.2.18 SoftHiZ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
9.2.19 HardHiZ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
9.2.20 GetStatus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
10 Package mechanical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
11 Revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63

L6470 List of tables
Doc ID 16737 Rev 2 5/64
List of tables
Table 1. Device summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Table 2. Absolute maximum ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Table 3. Recommended operating conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Table 4. Electrical characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Table 5. Pin description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Table 6. Typical application values . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Table 7. CL values according to external oscillator frequency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Table 8. Registers map. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
Table 9. EL_POS register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Table 10. MIN_SPEED register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
Table 11. Voltage amplitude regulation registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
Table 12. Winding resistance thermal drift compensation coefficient. . . . . . . . . . . . . . . . . . . . . . . . . 42
Table 13. ADC_OUT value and motor supply voltage compensation feature . . . . . . . . . . . . . . . . . . 42
Table 14. Overcurrent detection threshold . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
Table 15. Stall detection threshold . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
Table 16. STEP_MODE register. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
Table 17. Step mode selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
Table 18. SYNC output frequency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
Table 19. SYNC signal source . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
Table 20. ALARM_EN register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
Table 21. CONFIG register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
Table 22. Oscillator management. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
Table 23. External switch hard stop interrupt mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
Table 24. Overcurrent event . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
Table 25. Programmable power bridge output slew-rate values. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
Table 26. Motor supply voltage compensation enable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
Table 27. PWM frequency: integer division factor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
Table 28. PWM frequency: multiplication factor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
Table 29. Available PWM frequencies [kHz]: 8 MHz oscillator frequency . . . . . . . . . . . . . . . . . . . . . 48
Table 30. Available PWM frequencies [kHz]: 16 MHz oscillator frequency . . . . . . . . . . . . . . . . . . . . 49
Table 31. Available PWM frequencies [kHz]: 24 MHz oscillator frequency . . . . . . . . . . . . . . . . . . . . 49
Table 32. Available PWM frequencies [kHz]: 32 MHz oscillator frequency . . . . . . . . . . . . . . . . . . . . 50
Table 33. STATUS register. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
Table 34. STATUS register DIR bit. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
Table 35. STATUS register MOT_STATE bits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
Table 36. Application commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
Table 37. Nop command structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
Table 38. SetParam command structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54
Table 39. GetParam command structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54
Table 40. Run command structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
Table 41. Stepclock command structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
Table 42. Move command structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56
Table 43. GoTo command structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56
Table 44. GoTo_DIR command structure. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
Table 45. GoUntil command structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
Table 46. ReleaseSW command structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
Table 47. GoHome command structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
Table 48. GoMark command structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58

List of tables L6470
6/64 Doc ID 16737 Rev 2
Table 49. ResetPos command structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
Table 50. ResetDevice command structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
Table 51. SoftStop command structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
Table 52. HardStop command structure. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
Table 53. SoftHiZ command structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
Table 54. HardHiZ command structure. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
Table 55. GetStatus command structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
Table 56. HTSSOP28 mechanical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
Table 57. Document revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63

L6470 List of figures
Doc ID 16737 Rev 2 7/64
List of figures
Figure 1. Block diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Figure 2. Pin connection (top view) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Figure 3. Bipolar stepper motor control application using L6470 . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Figure 4. Charge pump circuitry. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Figure 5. Normal mode and microstepping (128 microsteps) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Figure 6. Speed profile in infinite acceleration/deceleration mode . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Figure 7. Constant speed commands examples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Figure 8. Positioning command examples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Figure 9. Motion commands examples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Figure 10. OSCIN and OSCOUT pins configurations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Figure 11. External switch connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Figure 12. Internal 3 V linear regulator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Figure 13. Current distortion and compensation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Figure 14. BEMF compensation curve. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
Figure 15. Motor supply voltage compensation circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
Figure 16. SPI timings diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Figure 17. Daisy-chain configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Figure 18. Command with three byte argument . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
Figure 19. Command with three byte responset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
Figure 20. Command response aborted . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
Figure 21. HTSSOP28 mechanical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62

Block diagram L6470
8/64 Doc ID 16737 Rev 2
1 Block diagram
Figure 1. Block diagram
AM02377v1
3V
Voltage Reg.
ADC
Ext. Osc. driver
&
Clock gen.
16MHz
Oscillator
Charge
pump
V DD
SPI Registers
Control
Logic
Current DACs
&
Comparators
Temperature
sensing
Current
sensing
STBY/RST
FLAG
CS
CK
SDO
SDI
BUSY/SYNC
SW
STCK
DGND
VDD OSCIN OSCOUT ADCIN VREG CP VBOOT
AGND
PGND
PGND
VSA
VSA
OUT1A
OUT2A
VSB
VSB
OUT1B
OUT2B
HS A1
LS A1
HS A2
LS A2
HS B1
LS B1
HS B2
LS B2
HS A1
LS A1
HS A2
LS A2
HS B1
LS B1
HS B2
LS B2
V DD
V boot V boot
V boot V boot

L6470 Electrical data
Doc ID 16737 Rev 2 9/64
2 Electrical data
2.1 Absolute maximum ratings
Table 2. Absolute maximum ratings
Symbol Parameter Test condition Value Unit
VDD Logic interface supply voltage 5.5 V
VSMotor supply voltage VSA = VSB = VS48 V
VGND, diff
Differential voltage between AGND, PGND
and DGND ±0.3 V
Vboot Bootstrap peak voltage 55 V
VREG
Internal voltage regulator output pin and logic
supply voltage 3.6 V
VADCIN
Integrated ADC input voltage range
(ADCIN pin) -0.3 to +3.6 V
VOSC OSCIN and OSCOUT pin voltage range -0.3 to +3.6 V
Vout_diff
Differential voltage between VSA, OUT1A,
OUT2A, PGND and VSB, OUT1B, OUT2B,
PGND pins
VSA = VSB = VS48 V
VLOGIC Logic inputs voltage range -0.3 to +5.5 V
Iout (1)
1. Maximum output current limit is related to metal connection and bonding characteristics. Actual limit must
satisfy maximum thermal dissipation constraints.
R.m.s. output current 3 A
Iout_peak (1) Pulsed output current TPULSE < 1 ms 7 A
TOP Operating junction temperature 150 °C
TsStorage temperature range -55 to 150 °C
Ptot Total power dissipation (TA= 25ºC) TBD TBD W
All pins
Maximum withstanding voltage range
Test condition: CDF-AEC-Q100-002- “human
body model”
Acceptance criteria “normal performance” all
pins vs. all pins
± 2000 V
Maximum withstanding voltage range
test condition: TBD - “charge device model”
all pins vs. all pins
TBD V

Electrical data L6470
10/64 Doc ID 16737 Rev 2
2.2 Recommended operating conditions
Table 3. Recommended operating conditions
Symbol Parameter Test condition Value Unit
VDD Logic interface supply voltage 3.3 V logic outputs 3.3 V
5 V logic outputs 5
VSMotor supply voltage VSA = VSB = VS845V
Vout_diff
Differential voltage between
VSA, OUT1A, OUT2A, PGND
and VSB, OUT1B, OUT2B,
PGND pins
VSA = VSB = VS45 V
VREG,in Logic supply voltage VREG voltage imposed
by external source 3.2 3.3 V
VADC
Integrated ADC input voltage
(ADCIN pin) 0V
REG V
TjOperating junction temperature - 25 125 °C

L6470 Electrical characteristics
Doc ID 16737 Rev 2 11/64
3 Electrical characteristics
VSA = VSB = 36 V; VDD = 3.3 V; internal 3 V regulator; TJ= 25°C, unless otherwise specified.
Table 4. Electrical characteristics
Symbol Parameter Test condition Min Typ Max Unit
General
VSthOn VSUVLO turn on threshold 7.5 8.2 8.9 V
VSthOff VSUVLO turn off threshold 6.6 7.2 7.8 V
VSthHyst VSUVLO threshold hysteresis 0.7 1 1.3 V
IqQuiescent motor supply current
Internal oscillator selected;
VREG = 3.3V ext;
CP floating
0.5 0.65 mA
Tj(WRN) Thermal warning temperature 130 °C
Tj(SD) Thermal shutdown temperature 160 °C
Charge pump
Vpump Voltage swing for charge pump oscillator 10 V
fpump,min Minimum charge pump oscillator frequency (1) 660 kHz
fpump,max Maximum charge pump oscillator frequency (1) 800 kHz
Iboot Average boot current fsw,A = fsw,B = 15.6 kHz
POW_SR = ‘10’ 1.1 1.4 mA
Output DMOS transistor
RDS(on)
High side switch ON resistance
Tj= 25 °C,
Iout = 3A 0.37
Ω
Tj= 125 °C, (2)
Iout = 3A 0.51
Low side switch ON resistance
Tj= 25 °C,
Iout = 3A 0.18
Tj= 125 °C, (2)
Iout = 3A 0.23
IDSS Leakage current OUT = VS3.1 mA
OUT = GND -0.3
trRise time (3)
POW_SR = '00', Iout = +1A 100
ns
POW_SR = '00', Iout = -1A 80
POW_SR = ‘11’, Iout = ±1A 100
POW_SR = ‘10’, Ilout = ±1A 200
POW_SR = ‘01’, Iout = ±1A 300

Electrical characteristics L6470
12/64 Doc ID 16737 Rev 2
tfFall time (3)
POW_SR = '00'; Iout = +1A 90
ns
POW_SR = '00'; Iout = -1A 110
POW_SR = ‘11’, Iout = ±1A 110
POW_SR = ‘10’, Iout = ±1A 260
POW_SR = ‘01’, Iload= ±1A 375
SRout_r Output rising slew-rate
POW_SR = '00', Iout = +1A 285
V/µs
POW_SR = '00', Iout = -1A 360
POW_SR = ‘11’, Iout = ±1A 285
POW_SR = ‘10’, Iout = ±1A 150
POW_SR = ‘01’, Iout = ±1A 95
SRout_f Output falling slew-rate
POW_SR = '00', Iout = +1A 320
V/µs
POW_SR = '00', Iout = -1A 260
POW_SR = ‘11’, Iout = ±1A 260
POW_SR = ‘10’, Iout = ±1A 110
POW_SR = ‘01’, Iout = ±1A 75
Dead time and blanking
tDT Dead time
POW_SR = '00' 250
ns
POW_SR = ‘11’,
fOSC = 16MHz 375
POW_SR = ‘10’,
fOSC = 16MHz 625
POW_SR = ‘01’,
fOSC = 16MHz 875
tblank Blanking time
POW_SR = '00' 250
ns
POW_SR = ‘11’,
fOSC = 16MHz 375
POW_SR = ‘10’,
fOSC = 16MHz 625
POW_SR = ‘01’,
fOSC = 16MHz 875
Source-drain diodes
VSD,HS High side diode forward ON voltage Iout = 1 A 1 1.1 V
VSD,LS Low side diode forward ON voltage Iout = 1 A 1 1.1 V
trrHS High side diode reverse recovery time Iout = 1 A 30 ns
trrLS Low side diode reverse recovery time Iout = 1 A 100 ns
Table 4. Electrical characteristics (continued)
Symbol Parameter Test condition Min Typ Max Unit

L6470 Electrical characteristics
Doc ID 16737 Rev 2 13/64
Logic inputs and outputs
VIL Low level logic input voltage 0.8 V
VIH High level logic input voltage 2 V
IIH High level logic input current (4) VIN = 5 V 1 µA
IIL Low level logic input current (5) VIN = 0 V -1 µA
VOL Low level logic output voltage (6)
VDD = 3.3 V,
IOL = 4 mA 0.3
V
VDD = 5 V,
IOL = 4 mA 0.3
VOH High level logic output voltage
VDD = 3.3 V,
IOH = 4 mA 2.4
V
VDD = 5 V,
IOH = 4 mA 4.7
RPU
RPD
CS Pull-up and STBY pull-down resistors CS = GND;
STBY/RST = 5 V 335 430 565 kΩ
Ilogic Internal logic supply current 3.3 V VREG externally
supplied, internal oscillator 3.7 4.3 mA
Ilogic,STBY Standby mode internal logic supply current 3.3 V VREG externally
supplied 22.5µA
fSTCK Step clock input frequency 2 MHz
Internal oscillator and external oscillator driver
fosc,i Internal oscillator frequency Tj = 25°C,
VREG = 3.3 V -3% 16 +3% MHz
fosc,e Programmable external oscillator frequency 8 32 MHz
VOSCOUTH OSCOUT clock source high level voltage
Internal oscillator
3.3 V VREG externally
supplied; IOSCOUT = 4 mA
2.4 V
VOSCOUTL OSCOUT clock source low level voltage
Internal oscillator
3.3 V VREG externally
supplied; IOSCOUT = 4 mA
0.3 V
trOSCOUT
tfOSCOUT
OSCOUT clock source rise and fall time Internal oscillator TBD ns
textosc Internal to external oscillator switching delay TBD ms
tintosc External to internal oscillator switching delay TBD µs
SPI
fCK,MAX Maximum SPI clock frequency (7) 5MHz
trCK
tfCK
SPI clock rise and fall time (5) TBD µs
Table 4. Electrical characteristics (continued)
Symbol Parameter Test condition Min Typ Max Unit

Electrical characteristics L6470
14/64 Doc ID 16737 Rev 2
thCK
tlCK
SPI clock high and low time (5) TBD ns
tsetCS Chip select setup time (5) TBD ns
tholCS Chip select hold time(5) TBD ns
tdisCS Deselect time (5) TBD ns
tsetSDI Data input setup time (5) TBD ns
tholSDI Data input hold time (5) TBD ns
tenSDO Data output enable time (5) TBD ns
tdisSDO Data output disable time (5) TBD ns
tvSDO Data output valid time (5) TBD ns
tholSDO Data output hold time (5) TBD ns
Switch input (SW)
RPUSW SW input pull-up resistance SW = GND 60 85 110 kΩ
PWM modulators
fPWM Programmable PWM frequency (1) fosc = 16MHz 2.8 62.5 kHz
fosc = 32MHz 5.6 125
NPWM PWM resolution 8 bit
Overcurrent protection
OCD_thMAX
Maximum programmable overcurrent
detection threshold OCD_TH = ‘1111’ 6 A
OCD_thMIN
Minimum programmable overcurrent detection
threshold OCD_TH = ‘0000’ 0.375 A
OCD_thRES
Programmable overcurrent detection threshold
resolution 0.375 A
tOCD,Flag OCD to Flag signal delay time dIout/dt = 350A/µs,
RFLAG = TBD 650 1000 ns
tOCD,SD OCD to shut-down delay time dIout/dt = 350A/µs
POW_SR = '10' 600 µs
VFLAG,
VBUSY
Open drain low level output voltage Iod = 4mA 0.3 V
Standby
IqSTBY
Quiescent motor supply current in standby
conditions
VS= 8V 26 34 µA
VS= 36V 30 36
tSTBY,min Minimum standby time 10 μs
tlogicwu Logic power-on and wake-up time 38 45 µs
Table 4. Electrical characteristics (continued)
Symbol Parameter Test condition Min Typ Max Unit

L6470 Electrical characteristics
Doc ID 16737 Rev 2 15/64
tcpwu Charge pump power-on and wake-up time
Power bridges disabled,
Cp= 10nF,
Cboot = 220nF
650 μs
Internal voltage regulator
VREG Voltage regulator output voltage 2.9 3 3.2 V
IREG Voltage regulator output current 40 mA
VREG, drop Voltage regulator output voltage drop IREG = 40mA 50 mV
IREG,STBY Voltage regulator standby output current 10 mA
Integrated analog to digital converter
NADC Analog to digital converter resolution 5 bit
VADC,ref Analog to digital converter reference voltage VREG V
fS
Analog to digital converter sampling
frequency fPWM kHz
1. Accuracy depends on oscillator frequency accuracy.
2. Tested at 25°C in a restricted range and guaranteed by characterization.
3. Rise and fall time depends on motor supply voltage value. Refer to SRout values in order to evaluate the actual rise and fall
time.
4. Not valid for STBY/RST pin which have internal pull-down resistor.
5. Not valid for SW and CS pins which have internal pull-up resistor
6. FLAG, BUSY and SYNC open drain outputs included.
7. See Figure 16– SPI timings diagram for details.
Table 4. Electrical characteristics (continued)
Symbol Parameter Test condition Min Typ Max Unit

Pin connection L6470
16/64 Doc ID 16737 Rev 2
4 Pin connection
4.1 Pin list
Figure 2. Pin connection (top view)
/54! /54!
63!
34"9<2%3
37
!$#).
62%'
/3#).
/3#/54
!'.$
#0
6"//4
0'.$
63"
/54" /54"
63"
6$$
3$/
#+
3$)
$'.$
"539<39.#
#3
&,!'
34#+
0'.$
63!




























%0!$
!-V
Table 5. Pin description
N. Name Type Function
17 VDD Power Logic outputs supply voltage (pull-up reference)
6VREG Power Internal 3 V voltage regulator output and 3.3 V external
logic supply
7 OSCIN Analog input
Oscillator pin 1. To connect an external oscillator or clock
source. If this pin is UNUSED, it should be connected to
ground.
8 OSCOUT Analog output
Oscillator pin 2. To connect an external oscillator. When
the internal oscillator is used this pin can supply a
2/4/8/16 MHz. If this pin is UNUSED, it should be left
floating.
10 CP Output Charge pump oscillator output
11 VBOOT Supply voltage Bootstrap voltage needed for driving the high side power
DMOS of both bridges (A and B)
5 ADCIN Analog input Internal analog to digital converter input
2VSA Power supply Full bridge A power supply pin. must be connected to
VSB
26

L6470 Pin connection
Doc ID 16737 Rev 2 17/64
12 VSB Power supply Full bridge B power supply pin. must be connected to
VSA
16
27 PGND Ground Power ground pin
13
1 OUT1A Power output Full bridge A output 1
28 OUT2A Power output Full bridge A output 2
14 OUT1B Power output Full bridge B output 1
15 OUT2B Power output Full bridge B output 2
9 AGND Ground Analog ground.
4 SW Logical input External switch input pin. If not used the pin should be
connected to VDD.
21 DGND Ground Digital ground
22 BUSY\SYNC Open drain output
By default this BUSY pin is forced low when the device is
performing a command. Otherwise the pin can be
configured to generate a synchronization signal.
18 SDO Logic output Data output pin for serial interface
20 SDI Logic input Data input pin for serial interface
19 CK Logic input Serial interface clock
23 CS Logic input Chip Select input pin for serial interface
24 FLAG Open drain output
Status Flag pin. An internal open drain transistor can pull
the pin to GND when a programmed alarm condition
occurs (step loss, OCD, thermal pre-warning or
shutdown, UVLO, wrong command, non performable
command)
3 STBY\RST Logic input
Standby and reset pin. LOW logic level reset the logic
and puts the device in standby mode. If not used, should
be connected to VDD
25 STCK Logic input Step clock input
EPAD Exposed pad Ground Internally connected to PGND, AGND and DGND pins
Table 5. Pin description (continued)
N. Name Type Function

Typical applications L6470
18/64 Doc ID 16737 Rev 2
5 Typical applications
Figure 3. Bipolar stepper motor control application using L6470
Table 6. Typical application values
Name value
CVS 220 nF
CVSPOL 100 µF
CREG 100 nF
CREGPOL 47 µF
CDD 100 nF
CDDPOL 10 µF
D1 BAT46SW or 2x 1N4148
CBOOT 220 nF
CFLY 10 nF
RPU 39 kΩ
RSW 100 Ω
CSW 10 nF
RA2.7 kΩ(VS = 36 V)
RB62 kΩ(VS = 36 V)

L6470 Functional description
Doc ID 16737 Rev 2 19/64
6 Functional description
6.1 Device power-up
At power-up end, the device state is the following:
●Registers are set to default,
●Internal logic is driven by internal oscillator and a 2MHz clock is provided by OSCOUT
pin,
●Bridges are disabled (High Z),
●UVLO bit in STATUS register is forced low (fail condition),
●FLAG output is forced low
During power-up the device is under reset (all logic IO disabled and power bridges in high
impedance state) until the following conditions are satisfied:
●VSis greater than VSthOn,
●VREG is greater than VREGth,
●Internal oscillator is operative.
Any motion command makes the device exiting from High Z state (HardStop and SoftStop
included).
6.2 Logic I/O
Pins CS, CK, SDI, STCK, SW and STBY\RST are TTL/CMOS 3.3V-5V compatible logic
inputs.
Pin SDO is a TTL/CMOS compatible logic output. VDD pin voltage sets the logic output pin
voltage range; when it is connected to VREG or 3.3V external supply voltage, the output is
3.3V compatible. When VDD is connected to a 5V supply voltage, SDO is 5V compatible.
VDD is not internally connected to VREG, an external connection is always needed.
A 10 µF capacitor should be connected to VDD pin in order to obtain a proper operation.
Pins FLAG and BUSY\SYNC are open drain outputs.
6.3 Charge pump
To ensure the correct driving of the high side integrated mosfets a voltage higher than the
motor power supply voltage needs to be applied to the VBOOT pin. The high side gate
driver supply voltage Vboot is obtained through an oscillator and a few external components
realizing a charge pump (see Figure 4).

Functional description L6470
20/64 Doc ID 16737 Rev 2
Figure 4. Charge pump circuitry
6.4 Microstepping
The driver is able to divide the single step into up to 128 microsteps. Stepping mode can be
programmed by STEP_SEL parameter in STEP_MODE register (see Ta b l e 1 7 ).
Step mode can be only changed when motor is stopped. Every time the step mode is
changed the electrical position (i.e. the point of microstepping sinewave that is generated) is
reset to first microstep and the absolute position counter value (see Section 6.5) becomes
meaningless.
Figure 5. Normal mode and microstepping (128 microsteps)
!-V
63
63 6
#0
6
$6 $
6#0
F05-0
TOHIGHSIDE
GATEDRIVERS
63
6
#0
6
$
#
"//4
#
&,9
$$
6"//4 #0
6$$
!-V
STEP STEPSTEP STEP STEP STEP
2ESET
POSITION
STEPSTEP STEP STEP
.ORMALDRIVING -ICROSTEPPING
0(!3%!CURRENT
0(!3%"CURRENT
0(!3%!CURRENT
0(!3%"CURRENT
MICROSTEPS

ª STEPS

ª STEPS

ª STEPS

ª STEPS
2ESET
POSITION