Power management

Posted on January 02, 2014 at 16:47In the BEMF compensation,  How can we evaluate the speed by ourselves? #evaluation-tool

Posted on June 26, 2014 at 03:57I'm builting a mini drive using the L6474. Got it all working and it runs smooth, but the driver runs very hot and I measured the charge pump and the voltage is only 5volts p-p max (manual says it should be 10vp-p)    The pump is running about 900K-1mhz but only swinging about 5 volts.  and when the motor is running slow, it goes as low as 3 .5 volts.    The slower you spin the motor the hotter  it gets, (very hot, over 100C) and when you speed it up it runs cooler.  Im guessing the upper mosfets aren't being fully turned on, generating the heat.   Any ideas ?

Posted on November 30, 2012 at 16:43Hello ST!We are using the L6470 and it is working quite well. But: We have problems when reading the ABS_POS register. It seems to be that the 8th Bit (for 128) is always Low. See Our values:   Go To Pos   Returned values   127  127  128  0  129  1  255  127  256  256  383  383  384  256  385  257 and so on. seems that the 8th bit (of 22) for the value 128 is always low.Is this a common issue? Does anyone have this problem too?How to slove this?Thanks! #l6470 #l6470-abs_pos

Posted on March 23, 2014 at 11:37I have designed a board using a L6482 chip. My L6482 has started, and I can send and receive messages a través de SPI bus, but now I have a problem: My STATUS register says: 1110 0000 0000 0011  (Get Status Command = 0xE003). It means:OCD = 1  --> overcurrentBUSY = 1  --> StoppedHiz = 1  --> Bridges in High Impedance State.The problem occurs even without connecting the stepper motor....! Just turn on the power, and my L6482 gets quite hot, but I have measured the total current of the board, and it is only 0.1 Amp. Configuration: I have read AN4354 and UM1685 Application note and User Manual, in order to calculate config values of my board: OCD_TH = 1000mVTCC =

Posted on June 26, 2014 at 12:43Hi, For our Medical Respirator equipment, We need Micro controller, Which is capable of controlling BLDC motor up to 60,000 RPM with minimum CPU utilization. Please suggest suitable microcontroller from ST. Thanks Kannan

Posted on May 25, 2013 at 00:01Hi Can one implement stall detection on the L6474? Thanks Andre

Posted on June 03, 2012 at 21:47hi , i am currently evaluate l6470 and have a few questions : 1. does the driver suitable for stepper motor with max 3A current per phase ? 2. how to obtain maximum holding torque ? ( setting K_HOLD to FFh ?) #go_until-error #l6470

Posted on June 20, 2014 at 07:29HiI'm using L6470.It works to move step motor a bit,when the Powered on.The motor's coil  Voltage was high between  the RESET turn high and First SPI communication is started.(Almost 10ms?CPU's order)I don't want to move a bit  when the IC powered on.What is the problem about that??SW terminal is LOW when the RESET turn high. #l6470-power-on-reset

Posted on June 17, 2014 at 11:15Dear all,I actually using two l6470 boards (to control two stepper motors), connected in daisy chain configuration also with STM32F4DIS-EXT.I don't understand very well how to control these drivers in STEP-CLOCK mode.For example, using the command dSPIN_Step_Clock(DIR) I noticed that the bit 15 of  the STATUS register (SCK_MOD) change only for one of the two motor and not change for the other: how can I switch both the drivers in STEP-CLOCK mode?Another problem is that I don't understand how control the movement of motors in this modality; in particular I read that in this modality the motor do a microstep every clock signal in that arrives in the STCK pin, but in which way it is possibile to control it (for example I would use the internal clock of the microcontroller).There is anyone that can help me or suggest some examples of code useful to a better understanding of STEP

Posted on June 11, 2014 at 10:51Dear all,my question is about how to realize a syncronous movement of 2 stepper motor (one move in X direction and one move in Y direction), controlling by 2 l6470 connected in a daisy chain configuration also with STM32F4DIS-EXT. In particular I would know if in this configuration's type there is a delay in sending the input command between the 2 motors, and which is the smartest way to obtain straight trajectories (i.e. have a simultaneous movement of both motors at the same speed)Actually I using commands:motor_Go_To_M1motor_Go_To_M2after calculation of the step that I want to realize with the 2 motorsThanks in advanceBest regardsMarco Cingolani

Posted on June 03, 2014 at 01:40I am working on a large system that is comprised of several different subsystems supplied with AC mains. In order to control inrush current to the system I want to build a controller that switches on AC duplex outlets at delayed times and the input mains should have in-rush current control.   My two questions are:     1. Not wanting to use relays, is an SSR a good approach to controlling AC mains in to AC out?     2. For inrush current control NTC's are ineffective. Could I use a pi filter network to do this? Or is a zero-crossing turnon SSR a better approach, or something else? Thanks,

Posted on October 25, 2013 at 00:06Hello, With L6472 I hear audible (high pitch) noise from motor when holding. volume of noise increase with increase hold current. It does not matter if the motor is loaded or not.When I look at winding with scope one pair is the typical pwm signal locked and duty cycle appropriate for the hold setpoint The other pair of windings appear ‘unlocked’ and much higher in frequency than the other winding. EVAL Bd hardware 24v supply, current set point .35amp Nema17, 18mh / 8.9ohms, 0.9degree step angleIs there a setting I am overlooking This does not occur with L6470. thanks for your support !

Posted on May 29, 2014 at 18:05Dear Enrico, I have the same problem of the other customer; I find this problem with two different family of sanyo denki's stepper motor (you can find the datasheet in the attachment): Type 103H7126-0140 and Type 103H7123-0140;  I tried your suggested configuration but the noise still remain; I have tryed the configuration suggested in document UM1688 pag.39/43 and the noise still remain; for testing, I'm using the evaluation board of the L6472; I have recorded a video that show the problem I speak; you can find the video at the following link: http://www.onetimebox.org/box/ugkLeeD3H2kgrrveg Do you have some suggestion that can help to solve this problem? Be

Posted on May 22, 2014 at 17:52Hello, I tried to poistioning my motor with the SPI command GoTo_DIR(DIR,ABS_POS). But then the motor turns a long time. So i run the command GetAbsPos, drive one step and run the command again. I wonder that one step changes the AbsPos value over 100.000 (I tried with full-step and 128-uStep). How can I understand the value from the AbsPos-register? #l6470-abs_pos

Posted on May 14, 2014 at 18:21I have 2 questions that I've posted to online support but haven't received a response. (1) I need clarification on the BRAKE input function - does it always short the 3 HS mosfets, independent of the ENA signal? I have independent signals driving the ENA_H and BRAKE_L pins (2) What are the cold-temperature limitations of this part? What is the distinction between 'max operation' at -40C vs. 'recommended operation' at -25C? What are the potential issues at -40C? What behavior might be expected at -55C (ignoring packaging-related issues)? Thanks, Kevin Spahr #l6235-bldc

Posted on April 11, 2014 at 14:47Hi,I'm tring to use a L6482 using only speed (Run) command because we have to use the motor in speed mode. Acc/Del are on our control. Chip Acc/Del are set to infinite (0xFFF) and MIN_SPEED/MAX_SPEED at 0,0x3FF. STEP_MODE is on 1/4 stepEverything works fine, I can read/write all registers.If  I give a Run command (0x50) motor runs at that frequency and CurrentSpeed register give use the Run frequency (divided by 4 because I use 1/4 microstep). Real frequency of the motor is also  correct.This is true only if  I write equal or greater speeds (i.e increase frequecy).If I try to decrease speed the motor runs at last speed and SPEED registry remain at that value. No way to decelerate. This happen if I give the RUN command  one shot or continuosly as well.Only if I execute a RUN( 0x00 ) the motor stop and SPEED goes at 0x00 as well.Th

Posted on May 22, 2014 at 11:42Our application:We have a Stainless steel disc diameter 30 cm, thickness 1mm, coupled with a chain to a stepper motor. The mechanical reduction is 1.5 (means that speed disc is slower than motor speed). Speed range of the motor starting from 0 to 400 steps/sec. Phase peak nominal current on each motor phase is 7A. Motor speed can change anytime continuosly.We use it in an agriculture automation, for a seeder.Used components: Stepper Motor: SLH-3431-700-8-AXT-00, 8 wires, Rated Phase Current 7A (10A parallel connection), Phase Resistance 0.76ohm, Phase Inductance 3.9mH. Driver: ST Microelectronics L6480Bridge Mosfets: Infineon BSC076N06NS3G (applied in same schematic as application board EVAL6480H). Protection: The whole electronic circuit is protected from power supply side with an automotive fuse rated 10A.Parameters:      &

Posted on May 21, 2014 at 11:31hi,Is it possible for a PC or Host Open a socket to connect the SPWFSxxx Wifi module.And how can I configure this module remotely via html page for example. #spwf01x #socket-server

Posted on May 21, 2014 at 01:24Hello, I am having problems with viper16, symptoms are identical to other people's posts. Power rises slowly and above set level (3.3v) . As soon as I power anything (microprocessor) voltage drops fast to 0v, if ciruit is disconnected voltage slowly rises again. I followed pdf manual and read it number of times but still can't make it work how it supposed to. Please help, my design became a paper weight because of this. #viper16

Posted on May 09, 2013 at 10:12I put in a technical support request on this but no response. I'm running a Viper16 in a simple non-isolated buck configuration as per the data sheet. There is a spark ignitor on the board and sometimes when the spark occurs, the Viper16 shuts down. I can understand it might go into one of its overload conditions but it does not recover. Vdd sits at 12V, 0.25V on FB and 0V on LIM and COMP. If I inject current into Vdd, the Viper16 starts again. Strange. Has anyone had this sort of problem with the Viper16 or other Viper chips?

Posted on May 11, 2014 at 10:57I'm evaluating L99ASC03 to control a brushless motor which drives a propeller. A series of LiPo accumulators will supply the board. The supply voltage is about 7V when 2 LiPo accumulators are used. When more LiPo accumulators are used, supply voltage increases up to 25 V in 3.7V steps. This supply voltage range matches the L99ASC03 internal +5V voltage regulator limits, but it may waste too much power when many LiPo are used. Is it possible to connect the +5V output of a switching regulator to the VSREG input while VS and VSMS are directly connected to the LiPo accumulators? Regards EtaPhi #bldc-motor-control #l99asc03

Posted on May 13, 2014 at 12:06Hi everyone, I'm driving 3 stepper motors in a daisy chain configuration. In order to start and stop all 3 motors the same time, I'm calculating the speed and acceleration values for each motor and write down the configuration. So far everything works fine! When I'm now trying to drive a long way with the first motor and a very short way with another motor the stopp time is not the same any more. The short path ends first. So there is a problem with the minimum speed I can reach... In the datasheet there's a note, that the minimum speed is 15,25 [steps/s] with the GoTo-command. I'm using 32 microsteps and the motors have a step angel of 1.8�. So the amount of microsteps per turn is 1.8[�]/32[microsteps] = 0,05625 [�/microstep] and 360[�]/0,05625[�/microstep] = 6400 [microsteps per turn]. Having a rising spindel with 2[mm], I get an amount of way per

Posted on April 23, 2014 at 16:19I have followed the Viper16 design tool and have followed the recommended components. The result is a voltage that is lower than expected (4.5v when expecting 5v) and dropping voltage as current increased from 5mA to 50mA drops to 4.2v. Looking at the FB input referenced to pin 1,2 GND it remains at 3.3v .... so why does the output drop? Has anyone got a Viper16 to work?

Posted on April 15, 2014 at 17:57I'm using TIM1 for a 6-step motor control on a STM32F2xx. According of the table 4 in DM0004234 application note, I update OCxE and OCxNE at each commutation, to select a new step. When OCxE = 0 and OCxNE = 0, the output is disabled. In this case, the output seems to be in high impedance. I would rather have it in OFF-state (low Z). Is there a way to get this result? Thanks for your help. Simon

Posted on April 21, 2014 at 15:48I am looking for a PCB footprint for the L6229Q VFQFPN 5 x 5 x 1.0 32 lead 0.050 pitch package.   Is there a footprint available that has been used successfully and is available to download anywhere?