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ST L6472 Manual

Manual is about: Fully integrated microstepping motor driver

Summary of L6472

  • Page 1

    This is information on a product in full production. March 2015 docid022729 rev 5 1/70 l6472 fully integrated microstepping motor driver datasheet - production data features  operating voltage: 8 - 45 v  7.0 a output peak current (3.0 a r.M.S. )  low r ds(on) power mosfets  programmable speed pr...

  • Page 2: Contents

    Contents l6472 2/70 docid022729 rev 5 contents 1 block diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 2 electrical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 2.1 absolute maximum ratings . ...

  • Page 3

    Docid022729 rev 5 3/70 l6472 contents 70 6.10 undervoltage lockout (uvlo) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 6.11 thermal warning and thermal shutdown . . . . . . . . . . . . . . . . . . . . . . . . . 29 6.12 reset and standby . . . . . . . . . . . . . . . . . . . ....

  • Page 4

    Contents l6472 4/70 docid022729 rev 5 9.1.15 ocd_th . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47 9.1.16 step_mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47 9.1.17 alarm_en . . . . . . . . . . . ....

  • Page 5: List of Tables

    Docid022729 rev 5 5/70 l6472 list of tables 70 list of tables table 1. Device summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 table 2. Absolute maximum ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...

  • Page 6

    List of tables l6472 6/70 docid022729 rev 5 table 48. Resetdevice command structure. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61 table 49. Softstop command structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ....

  • Page 7: List of Figures

    Docid022729 rev 5 7/70 l6472 list of figures 70 list of figures figure 1. Block diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 figure 2. Htssop28 pin connection (top view) . . . . . . . . . . . . . . . . . . . . . . ....

  • Page 8: 1 Block

    Block diagram l6472 8/70 docid022729 rev 5 1 block diagram figure 1. Block diagram $0y 9 9rowdjh5hj $'& ([w2vfgulyhu &orfnjhq 0+] 2vfloodwru &kdujh sxps 9 '' 63, 5hjlvwhuv &rqwuro /rjlf &xuuhqw'$&v &rpsdudwruv 7hpshudwxuh vhqvlqj &xuuhqw vhqvlqj 67%567 )/$* &6 &. 6'2 6', %866 6: 67&. '*1' 9'' 26&,1 ...

  • Page 9: 2 Electrical

    Docid022729 rev 5 9/70 l6472 electrical data 70 2 electrical data 2.1 absolute maximum ratings 2.2 recommended operating conditions table 2. Absolute maximum ratings symbol parameter test condition value unit v dd logic interface supply voltage 5.5 v v s motor supply voltage v sa = v sb = v s 48 v v...

  • Page 10: 2.3 Thermal

    Electrical data l6472 10/70 docid022729 rev 5 2.3 thermal data table 4. Thermal data symbol parameter package typ. Unit r thja thermal resistance junction ambient htssop28 (1) 22 °c/w powerso36 (2) 12 1. Htssop28 mounted on the eval6472h rev 1.0 board: four-layer fr4 pcb with a dissipating copper su...

  • Page 11: 3 Electrical

    Docid022729 rev 5 11/70 l6472 electrical characteristics 70 3 electrical characteristics v sa = v sb = 36 v; v dd = 3.3 v; internal 3 v regulator; t j = 25 °c, unless otherwise specified. Table 5. Electrical characteristics symbol parameter test condition min. Typ. Max. Unit general v sthon v s uvlo...

  • Page 12

    Electrical characteristics l6472 12/70 docid022729 rev 5 t f fall time (3) pow_sr = '00'; i out = +1 a 90 ns pow_sr = '00'; i out = -1 a 110 pow_sr = ‘11’, i out = ±1 a 110 pow_sr = ‘10’, i out = ±1 a 260 pow_sr = ‘01’, i load = ±1 a 375 sr out_r output rising slew rate pow_sr = '00', i out = +1 a 2...

  • Page 13

    Docid022729 rev 5 13/70 l6472 electrical characteristics 70 i il low logic level input current (5) v in = 0 v -1 µa v ol low logic level output voltage (6) v dd = 3.3 v, i ol = 4 ma 0.3 v v dd = 5 v, i ol = 4 ma 0.3 v oh high logic level output voltage v dd = 3.3 v, i oh = 4 ma 2.4 v v dd = 5 v, i o...

  • Page 14

    Electrical characteristics l6472 14/70 docid022729 rev 5 t dissdo data output disable time (7) 47 ns t vsdo data output valid time (7) 57 ns t holsdo data output hold time (7) 37 ns switch input (sw) r pusw sw input pull-up resistance sw = gnd 60 85 110 k current control i step,max max. Programmable...

  • Page 15

    Docid022729 rev 5 15/70 l6472 electrical characteristics 70 integrated analog-to-digital converter n adc analog-to-digital converter resolution 5 bit v adc,ref analog-to-digital converter reference voltage v reg v f s analog-to-digital converter sampling frequency f osc / 512 khz 1. Accuracy depends...

  • Page 16: 4 Pin

    Pin connection l6472 16/70 docid022729 rev 5 4 pin connection figure 2. Htssop28 pin connection (top view) 345 figure 3. Powerso36 pin connection (top view) 1(/% 065" 065" 74" 74" 45#:345 48 "%$*/ 04$*/ 04$065 065# "(/% $1 7#005 74# 74# 73&( 065# 065" 065" 74" 74" 45$, '-"( $4 #64:=4:/$ &1"% %(/% 4%...

  • Page 17: Pin List

    Docid022729 rev 5 17/70 l6472 pin connection 70 pin list table 6. Pin description number name type function powerso htssop 24 17 vdd power logic output supply voltage (pull-up reference) 9 6 vreg power internal 3 v voltage regulator output and 3.3 v external logic supply 10 7 oscin analog input osci...

  • Page 18

    Pin connection l6472 18/70 docid022729 rev 5 31 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). 6 3 stby\rs...

  • Page 19: 5 Typical

    Docid022729 rev 5 19/70 l6472 typical applications 70 5 typical applications figure 4. Bipolar stepper motor control application using the l6472 table 7. Typical application values name value c vs 220 nf c vspol 100 µf c reg 100 nf c regpol 47 µf c dd 100 nf c ddpol 10 µf d1 charge pump diodes c boo...

  • Page 20: 6 Functional

    Functional description l6472 20/70 docid022729 rev 5 6 functional description 6.1 device power-up at the end of power-up, the device state is the following: registers are set to default internal logic is driven by the internal oscillator and a 2 mhz clock is provided by the oscout pin bridges are di...

  • Page 21: 6.4 Microstepping

    Docid022729 rev 5 21/70 l6472 functional description 70 figure 5. Charge pump circuitry 6.4 microstepping the driver is able to divide the single step into up to 16 microsteps. Step mode can be programmed by the step_sel parameter in the step_mode register (see table 20 on page 47 ). Step mode can o...

  • Page 22

    Functional description l6472 22/70 docid022729 rev 5 figure 6. Normal mode and microstepping (16 microsteps) automatic full-step mode when motor speed is greater than a programmable full-step speed threshold, the l6472 switches automatically to full-step mode (see figure 7 ); the driving mode return...

  • Page 23: 6.5

    Docid022729 rev 5 23/70 l6472 functional description 70 6.5 absolute position counter an internal 22-bit register (abs_pos) keeps track of the motor motion according to the selected step mode; the stored value unit is equal to the selected step mode (full, half, quarter, etc.). The position range is...

  • Page 24

    Functional description l6472 24/70 docid022729 rev 5 6.7.1 constant speed commands a constant speed command produces a motion in order to reach and maintain a user defined target speed starting from the programmed minimum speed (set in the min_speed register) and with the programmed acceleration/dec...

  • Page 25

    Docid022729 rev 5 25/70 l6472 functional description 70 figure 9. Positioning command examples 6.7.3 motion commands motion commands produce a motion in order to perform a user-defined number of microsteps in a user-defined direction that are sent to the device together with the command (see figure ...

  • Page 26

    Functional description l6472 26/70 docid022729 rev 5 the hardstop command stops the motor instantly, ignoring deceleration constraints and maintaining the rotor position (a holding torque is applied). The softhiz command causes the motor to decelerate with a programmed deceleration value until the m...

  • Page 27: 6.8

    Docid022729 rev 5 27/70 l6472 functional description 70 6.8 internal oscillator and oscillator driver the control logic clock can be supplied by the internal 16-mhz oscillator, an external oscillator (crystal or ceramic resonator) or a direct clock signal. These working modes can be selected by the ...

  • Page 28: 6.9 Overcurrent

    Functional description l6472 28/70 docid022729 rev 5 figure 11. Oscin and oscout pin configurations note: when oscin is unused, it should be left floating. When oscout is unused it should be left floating. 6.9 overcurrent detection when the current in any of the power mosfets exceeds a programmed ov...

  • Page 29: 6.10 Undervoltage

    Docid022729 rev 5 29/70 l6472 functional description 70 warning: the overcurrent shutdown is a critical protection feature. It is not recommended to disable it. 6.10 undervoltage lockout (uvlo) the l6472 provides motor supply uvlo protection. When the motor supply voltage falls below the v sthoff th...

  • Page 30: 6.13

    Functional description l6472 30/70 docid022729 rev 5 on exiting standby mode the bridges are disabled (hiz flag high) and whichever motion command causes the device to exit high z state (hardstop and softstop included). Warning: it is not recommended to reset the device when outputs are active. The ...

  • Page 31: 6.15 Integrated

    Docid022729 rev 5 31/70 l6472 functional description 70 6.15 integrated analog-to-digital converter the l6472 integrates an n adc bit ramp-compare analog-to-digital converter with a reference voltage equal to vreg. The analog-to-digital converter input is available through the adcin pin and the conv...

  • Page 32: 6.17 Busy\sync

    Functional description l6472 32/70 docid022729 rev 5 6.17 busy\sync pin this pin is an open drain output which can be used as the busy flag or synchronization signal according to the sync_en bit value (step_mode register). 6.17.1 busy operation mode the pin works as busy signal when the sync_en bit ...

  • Page 33: Phase Current Control

    Docid022729 rev 5 33/70 l6472 phase current control 70 7 phase current control the l6472 performs a new current control technique, named predictive current control, allowing the device to obtain the target average phase current. This method is described in detail in section 7.1 . Furthermore, the l6...

  • Page 34: 7.2

    Phase current control l6472 34/70 docid022729 rev 5 at the end of the predictive on state the power stage is set in the off state for a fixed time, as in a constant t off current control. During the off state both slow and fast decay can be performed; the better decay combination is automatically se...

  • Page 35

    Docid022729 rev 5 35/70 l6472 phase current control 70 figure 16. Adaptive decay - fast decay tuning when two or more fast decays are performed with the present target current, the control system adds a fast decay at the end of every off time, keeping the off state duration constant (t off is split ...

  • Page 36: 7.3

    Phase current control l6472 36/70 docid022729 rev 5 7.3 auto-adjusted fast decay during the falling steps when the target current is decreased by a microstep change (falling step), the device performs a fast decay in order to reach the new value as fast as possible. Anyway, exceeding the fast durati...

  • Page 37: 7.4

    Docid022729 rev 5 37/70 l6472 phase current control 70 figure 18. Fast decay tuning during the falling steps 7.4 torque regulation (output current amplitude regulation) the output current amplitude can be regulated in two ways: writing the tval_acc, tval_dec, tval_run and tval_hold registers or vary...

  • Page 38: 8 Serial

    Serial interface l6472 38/70 docid022729 rev 5 8 serial interface the integrated 8-bit serial peripheral interface (spi) is used for a synchronous serial communication between the host microprocessor (always master) and the l6472 (always slave). The spi uses chip select (cs), serial clock (ck), seri...

  • Page 39

    Docid022729 rev 5 39/70 l6472 serial interface 70 figure 20. Daisy chain configuration.

  • Page 40: 9 Programming

    Programming manual l6472 40/70 docid022729 rev 5 9 programming manual 9.1 register and flag description table 9 shows a map of the user registers available (detailed description in respective paragraphs from section 9.1.1 on page 41 to section 9.1.19 on page 52 ): table 9. Register map address [hex]...

  • Page 41

    Docid022729 rev 5 41/70 l6472 programming manual 70 9.1.1 abs_pos the abs_pos register contains the current motor absolute position in agreement to the selected step mode; the stored value unit is equal to the selected step mode (full, half, quarter, etc.). The value is in 2's complement format and ...

  • Page 42

    Programming manual l6472 42/70 docid022729 rev 5 9.1.3 mark the mark register contains an absolute position called mark, in accordance with the selected step mode; the stored value unit is equal to the selected step mode (full, half, quarter, etc.). It is in 2's complement format and it ranges from ...

  • Page 43

    Docid022729 rev 5 43/70 l6472 programming manual 70 in order to convert the dec value in step/s2 the following formula can be used: equation 3 where dec is the integer number stored in the register and tick is 250 ns. The available range is from 14.55 to 59590 step/s 2 with a resolution of 14.55 ste...

  • Page 44

    Programming manual l6472 44/70 docid022729 rev 5 9.1.9 fs_spd the fs_spd register contains the threshold speed. When the actual speed exceeds this value the step mode is automatically switched to full-step two-phase on. Its value is expressed in step/tick (format unsigned fixed point 0.18) and to co...

  • Page 45

    Docid022729 rev 5 45/70 l6472 programming manual 70 9.1.11 t_fast the t_fast register contains the maximum fast decay time (toff_fast) and the maximum fall step time (fall_step) used by the current control system (see section 7.2 on page 34 and 7.3 on page 36 for details): the available range for bo...

  • Page 46

    Programming manual l6472 46/70 docid022729 rev 5 9.1.13 toff_min the toff_min register contains the minimum off time value used by the current control system (see section 7.1 on page 33 for details). The available range for both parameters is from 0.5 µs to 64 µs. Any attempt to write to the registe...

  • Page 47

    Docid022729 rev 5 47/70 l6472 programming manual 70 9.1.15 ocd_th the ocd_th register contains the overcurrent threshold value (see section 6.9 on page 28 for details). The available range is from 375 ma to 6 a, steps of 375 ma, as shown in table 18 . 9.1.16 step_mode the step_mode register has the ...

  • Page 48

    Programming manual l6472 48/70 docid022729 rev 5 any attempt to write the register when the motor is running causes the command to be ignored and the notperf_cmd flag to rise (see section 9.1.19 ). When when sync_en bit is set low, busy/sync output is forced low during the commands execution, otherw...

  • Page 49

    Docid022729 rev 5 49/70 l6472 programming manual 70 9.1.17 alarm_en the alarm_en register allows the selection of which alarm signals are used to generate the flag output. If the respective bit of the alarm_en register is set high, the alarm condition forces the flag pin output down. 9.1.18 config t...

  • Page 50

    Programming manual l6472 50/70 docid022729 rev 5 the osc_sel and ext_clk bits set the system clock source: the sw_mode bit sets the external switch to act as hardstop interrupt or not: the oc_sd bit sets if an overcurrent event causes or not the bridges to turn off; the ocd flag in the status regist...

  • Page 51

    Docid022729 rev 5 51/70 l6472 programming manual 70 the pow_sr bits set the slew rate value of the power bridge output: the tqreg bit sets if the torque regulation (see section 7.4 on page 37 ) is performed through adcin voltage (external) or the tval_hold, tval_acc, tval_dec and tval_run registers ...

  • Page 52

    Programming manual l6472 52/70 docid022729 rev 5 9.1.19 status when the hiz flag is high it indicates that the bridges are in high-impedance state. Any motion command causes the device to exit from high z state (hardstop and softstop included), unless error flags forcing a high z state are active. T...

  • Page 53

    Docid022729 rev 5 53/70 l6472 programming manual 70 mot_status indicates the current motor status: any attempt to write to the register causes the command to be ignored and the notperf_cmd to rise. Table 33. Status register mot_status bits mot_status motor status 0 0 stopped 0 1 acceleration 1 0 dec...

  • Page 54: 9.2 Application

    Programming manual l6472 54/70 docid022729 rev 5 9.2 application commands a summary of commands is given in table 34 . Table 34. Application commands command mnemonic command binary code action [7 … 5] [4] [3] [2 …1] [0] nop 000 0 0 00 0 nothing setparam (param, value) 000 [param] writes value in th...

  • Page 55

    Docid022729 rev 5 55/70 l6472 programming manual 70 9.2.1 command management the host microcontroller can control motor motion and configure the l6472 device through a complete set of commands. All commands are composed by a single byte. After the command byte, some argument bytes should be needed (...

  • Page 56

    Programming manual l6472 56/70 docid022729 rev 5 9.2.2 nop nothing is performed. 9.2.3 setparam (param, value) the setparam command sets the param register value equal to value; param is the respective register address listed in table 9 on page 40 . The command should be followed by the new register...

  • Page 57

    Docid022729 rev 5 57/70 l6472 programming manual 70 this command reads the current param register value; param is the respective register address listed in table 9 on page 40 . The command response is the current value of the register (most significant byte first). The number of bytes composing the ...

  • Page 58

    Programming manual l6472 58/70 docid022729 rev 5 stepclock command argument and can by changed by a new stepclock command without exiting step-clock mode. Events that cause bridges to be forced into high-impedance state (overtemperature, overcurrent, etc.) do not cause the device to leave step-clock...

  • Page 59

    Docid022729 rev 5 59/70 l6472 programming manual 70 this command can only be given when the previous motion command has been completed (busy flag released). Any attempt to perform a goto command when a previous command is under execution (busy low) causes the command to be ignored and the notperf_cm...

  • Page 60

    Programming manual l6472 60/70 docid022729 rev 5 if the sw_mode bit of the config register is set low, the external switch turn-on event causes a hardstop interrupt instead of the softstop one (see section 6.13 on page 30 and 9.1.18 on page 49 ). This command keeps the busy flag low until the switch...

  • Page 61

    Docid022729 rev 5 61/70 l6472 programming manual 70 9.2.13 gomark the gomark command produces a motion to the mark position performing the minimum path. Note that this command is equivalent to the “goto (mark)” command. If a motor direction is mandatory the goto_dir command must be used. The gomark ...

  • Page 62

    Programming manual l6472 62/70 docid022729 rev 5 9.2.16 softstop the softstop command causes an immediate deceleration to zero speed and a consequent motor stop; the deceleration value used is the one stored in the dec register (see section 9.1.6 on page 42 ). When the motor is in high-impedance sta...

  • Page 63

    Docid022729 rev 5 63/70 l6472 programming manual 70 9.2.19 hardhiz the hardhiz command immediately disables the power bridges (high-impedance state) and raises the hiz flag. When the motor is stopped, a hardhiz command forces the bridges to enter high- impedance state. This command can be given anyt...

  • Page 64: 10 Package

    Package information l6472 64/70 docid022729 rev 5 10 package information in order to meet environmental requirements, st offers these devices in different grades of ecopack ® packages, depending on their level of environmental compliance. Ecopack specifications, grade definitions and product status ...

  • Page 65: 10.1

    Docid022729 rev 5 65/70 l6472 package information 70 10.1 htssop28 package information figure 24. Htssop28 package outline.

  • Page 66

    Package information l6472 66/70 docid022729 rev 5 table 54. Htssop28 package mechanical data symbol dimensions (mm) min. Typ. Max. A 1.2 a1 0.15 a2 0.8 1.0 1.05 b 0.19 0.3 c 0.09 0.2 d (1) 1. Dimension “d” does not include mold flash, protrusions or gate burrs. Mold flash, protrusions or gate burrs ...

  • Page 67: 10.2

    Docid022729 rev 5 67/70 l6472 package information 70 10.2 powerso36 package information figure 25. Powerso36 package outline h d $ ( d 3620(& '(7$,/$ ' ( ( k[Û '(7$,/$ ohdg voxj d 6 *djh3odqh / '(7$,/% '(7$,/% &23/$1$5,7 * & & 6($7,1*3/$1( h f 1 1 0 $ % e % $ + ( ' %277209,(:.

  • Page 68

    Package information l6472 68/70 docid022729 rev 5 table 55. Powerso36 package mechanical data symbol dimensions (mm) min. Typ. Max. A 3.60 a1 0.10 0.30 a2 3.30 a3 0 0.10 b 0.22 0.38 c 0.23 0.32 d (1) 1. Dimension “d/e1” does not include mold flash, protrusions or gate burrs. Mold flash, protrusions ...

  • Page 69: 11 Revision

    Docid022729 rev 5 69/70 l6472 revision history 70 11 revision history table 56. Document revision history date revision changes 24-jan-2012 1 initial release. 09-jan-2013 2 changed the title. Changed t op value in table 2 . Removed t j parameter in table 3 . Added footnote to table 9 . Changed fast ...

  • Page 70

    L6472 70/70 docid022729 rev 5 important notice – please read carefully stmicroelectronics nv and its subsidiaries (“st”) reserve the right to make changes, corrections, enhancements, modifications, and improvements to st products and/or to this document at any time without notice. Purchasers should ...