Power management

Posted on January 09, 2018 at 09:38Hello community,i got a problem when i want to create on my stm8 eval board a pwm signal with 350khz and variable duty cycle from 0-100.i calculate the the values for the registers as follows:PWM Frequency = Clock of the Timer without Prescaler (16Mhz) / ARR +1 --> i choosed for arr 44 so i get apprx. 355kHzBut know i can not achieve the desired pwm resolution of 100, now i have 45 steps instead of 100.Did you guys know how to solve this problem?Thanks a lot

Posted on January 06, 2018 at 01:24Three questions regarding MC_SixStep_Ramp_Motor_calc()1.) What unit do the mechanical acceleration rate parameters/variables have? (apparently not 1/min/s or rad/s²)2.) 'mech_accel_hz = SIXSTEP_parameters.ACCEL * Rotor_poles_pairs / 60' - so 'mech_accel_hz' is rather the electrical acceleration than mechanical?3.) I found that MCM_Sqrt() takes 1,3 .. 1,8 ms (32 MHz CCLK) while the (ARM-MDK) math library's sqrt() takes 150 .. 250µs. What is the benefit of using MCM_Sqrt()?Thanks for comments.

Posted on January 04, 2018 at 18:11Hi,I have just started working on a configuration wizard utility in Keil uVision for the setup of stepper motors.As can be seen, the configuration wizard so far setups the acceleration, deceleration, maximum and minimum speed etc. of the motor just fine.However, for the distance per step option I would like to use a decimal point number, say 9.4 mm per step.  However the configuration wizard is not allowing me to enter decimal point numbers.Is this a limitation of the configuration wizard or is there a method of entering decimal point numbers?Any answers are greatly appreciated.Thanks,Ernest

Posted on December 28, 2017 at 12:28Hi!Fatal error: Slected core ( Cortex-M3) is not same as the target core ( Cortex-M0)Session aborted!With STEVAL-SPIN3202, even the compile goes well, and the above error occurs on the link. I do not know why. Thank you for your advice.Device = ST STM32F103CB, Core = Cortex-M3

Posted on December 18, 2017 at 03:40 I brought a 'STEVAL-SPIN3202'. It based 'STSPIN32F0A'.But main-chip written as follows.-----------------------------------------SPIN32F0FN02U A5THA 11 722ST @ A-----------------------------------------Is this 'STSPIN32F0' or 'STSPIN32F0A' ?

Posted on June 24, 2017 at 22:25I'm using the SPIN3201 eval board and have had it working in sensor-less and Hall modes, but i'm looking for better low very low speed, < 10 rpm behaviour where the halls don't produce smooth torque. I've attached a 1000 pulse quadrature encoder and from the monitor in ST Motor Control i can see RPM when i turn the motor by hand so i believe it correctly connect or it wouldn't report motion. However, i cant get the motor to move, the alignment step doesn't seem to do anything, as i understand it should drive one coil to pull the motor to a known position, but it doesn't, though it reports success in the ST Motor Control Monitor. Then when i try and start the motor i get nothing, no moment, no sounds, no volts on the terminals also no error.Any one got any hints what i'm doing wrong?Thanks Tim

Posted on October 31, 2017 at 01:26There seems to be an error in either the datasheet or the applicatio note of the STC3117 gas gauge.The error is in the bit description of the REG_MODE register, specifically the VMODE bit. The datasheet says the following:VMODE = 0 - mixed modeVMODE = 1 - power saving voltage mode The application note says the opposite:VMODE = 1 - mixed modeVMODE = 0 - power saving voltage mode I've attached screenshots of the relevant sections in both the datasheet and the application note. This first screenshot is from the datasheet.

Posted on December 13, 2017 at 10:28At the maximum, how many BLDC motors can be controlled using one STSPIN32F0A?If I happen to use only Brushed DC Motors, how many such DC motors can be controlled simultaneously using one STSPIN32F0A? #motors #motor-driver

Posted on December 13, 2017 at 08:36Hi. I would like to set a battery float voltage to 4.1v (to extend the life of the battery). Looking at the datasheet for the li-ion battery charger STBC02, it looks like this can be adjusted but 4.2v seems to be the min value (equation 3 on page 18).Am I missing something, surely it would be a good feature to allow lower float voltages?ThanksPhil

Posted on December 13, 2017 at 06:34Hi,To serially control Brushed DC motors using STSPIN32F0A.I would like to connect a bluetooth module HC-05 through the USART1's PB6 and PB7.What are the connections I need to give for the brushed DC Motors?How many Brushed DC motors can be controlled simultaneously?Soliciting a quick reply. Thanks in advance!#stspin32f0a #motor-driver #brush-dc-motor

Posted on December 11, 2017 at 19:55In the STEVAL-ISB035V1 Manual (UM2132), the schematic and ball-out refer to the STBC02 instead of the -03. Also, on the board, both R11 (in the '02' section') and R8/ R13 (in the '03' section) are installed. This doesn't seem right, since BATMS_EN should be high or low, not divided.A hyperlink in datasheets would be useful for reporting mistakes. #stbc03

Posted on September 28, 2016 at 19:51Hello,We are using a STC3115 in one of our designs. The problem is that it does not start up.I read: https://github.com/st-sw/STC3115GenericDriver/wiki/STC3115-FAQIt looks like the problem is that the BATD is 'high'. I tried to force it low by connecting it to ground through a 1K resistor. However, the output of BATD is still 3.7V. Is there a way I can force it to become 'low'?On the software side:- I can communicate via I2C. The counter value reads: 1. So it seems that it starts, but then stops.- A soft reset does not help- I call BatterMonitorInit once BatteryReadStateOfCharge is called ever

Posted on May 15, 2017 at 09:54We are having cases where Fuel gauge IC (STC3115) get stuck during Long run. It has been found that SDA remains low in this case. In order to recover from such situation I am planning to reset the fuel gauge.Is there any method to reset the STC3115 IC other than Power-On Reset and Soft Reset ? As per data-sheet the functionality of RSTIO is Reset Sense Input and Reset Control Output. Can we use this pin to reset the STC3115 chip ?#stc3115-issue-startup #stc3115 #stc3115-i2c-issue-timing

Posted on December 05, 2017 at 12:51Dear forum,I'm trying to use GUI from SPINFamily Evaluation Tool 3.2 on windows 10 PC and Eval6470H-DISC R1 by USB.My computer cannot recoognize the board. Installing drivers from : - STMicroelectronics\SPINFamily Evaluation Tool 3.2\Updater\Drivers. Starting GUI cannot connect to board. Many different tries without results.Could you help me ?

Posted on November 16, 2017 at 13:06Hello,On my nucleo-l073 board, my software can run in stop mode and consumes only 3uA. I decided to make my own PCB but i can't figure out why the consumption can't reach 3uA. Actually, i'm running around 25uA with the same software. I'm using a stencil and a reflow oven to solder the components (T-962) and the solder paste is a Sn63 Pb37. I'm making the pcb by PCBway and i take the cheapest quality (5$ for 10 pieces : TG 130-140 (i don't what it means)), do you think it could come from that ?I have also noticed when i put my finger directly on the stm32, consumption often decreases.If you have any ideas, please feel free to share Thank you in advance.Edit : I join in attached file my schematic and my PCB (the ground planes are not displayed)Best regards,Aur�lien#stop-mode #low-power #stm32 #pcb #nucleo-l073rz #pcbway

Posted on November 29, 2017 at 09:18Hi,As mentioned, input voltage is 48VDC and there is up to 40A available. I would like to be able use all this to drive our motor (custom IPM). I am free to design the driver board with 3-shunt current sensing and voltage sensing. There will be a position sensor. (I hope not to need this position sensor, but for now I have it to make sure there is enough torque at startup). I want to run FOC in torque mode. PWM frequency just outside audible range.For the gate driver I have found DRV832x and for the mosfets I have found CSD88599Q5DC (half-bridge).- Am I overestimating how much power these mosfets can deliver?- Any other device suggestions?- Any reason these should be hard to use with ST's FOC uC and SW?Which microcontroller should I choose? STM32F303 something? The microcontroller won't do anything else than driving this motor.Is there any way I could drive 3 i

Posted on August 15, 2017 at 11:49Hello,I am using 'L6482H discovery board' design example for L6482 chip, for making my own pcb board, using the same mosfets, etc.At this moment, my board runs really well with 2A stepper motors and 80 mili-ohm R sense resistors. Both commands, Move (DIR, N_STEP) and Run (DIR, SPD),  run very well.But when I use Run (DIR, SPD) command with 3A stepper motors, stepper motors almost do not have any torque, and it is easy to block the axis. Only at very low speed they have some  torque.I understand I have to change my R sense values, but I am not sure the way of calculating this value for 3A stepper motors.Please, what is the way of calculating the right value of R sense?Thanks in advance,Valentin#l6482h #l6482 #r-sense

Posted on November 07, 2017 at 12:32Hi everyone, I am planning to use sic mosfets in inverter application(2 level or 3 level) and I searched some manufacturer and prices, I saw sct30n120 and ST says ' Very fast and robust intrinsic body diode (no need for external freewheeling diode, thus more compact systems)' , does intrinsic body diode can handle the current as much as the mosfet ? lets say 25A current , or should I use external body diode ? If I use external body diode; can I use fast recovery diode ? What will be the disadvantages of that.External SiC SBD's are expensive #sic-mosfet #sbd #sct30n120

Posted on November 02, 2017 at 14:22I am seeing very noisy measurements on shunt adc.I attached schematics and gerbers.Could suggest how to eliminate noise on adc lines (line connected to shunt and going to STM32F303 chip?regards#adc #l6206pd #noise

Posted on July 19, 2017 at 11:39I noticed there are two lib files in Cortex-M4 core MCU:MC_Library_ProtectedSources_SD_CM4_CCM_MKD.lib and MC_Library_ProtectedSources_single_drive_CM4_MKD.libI can't find any description for the diffrence between them, so I should choice which one in my application?thank you.

Posted on November 25, 2017 at 08:36I am using STNS01 to charge a lithium battery (2600mAh). LED is blinking at frequency of 1Hz. ICHG resistor is 1K ohm and 10K ohm thermistor is used. I tried changing both, but still led is blinking.#led-blinking #stns01

Posted on November 19, 2017 at 11:24 Hi! I collect a three-phase control circuit (6kW). I want to use BTA16 (Snubberless and standard Triacs) Whether correctly I understand, that for type Standard it is necessary to include in parallel TVS a diode. And for the Snubberless TVS type, the diode will be superfluous (because it is already built in)? Thank you. Sorry for my english. #triac #tvs #ac-motor-control

Posted on November 18, 2017 at 07:46Dear Sir,i am using stm8s mc library for 3 phase bldc motor(1kw).motor is running perfectly.my problem is when motor is running we are getting some blich in hall sensor ( 300us ) output. that is why motor is getting some stalking condition.is there any method to skip the blich(300us) in sensing the hall sensor or driving the mosfet ??thanks.

Posted on October 28, 2017 at 07:17       Hi Can I connect the positive output voltage terminal of my off-line power supply using Viper16L to AC-main's (N) terminal (doesn't make sense though) to trigger a snubberless triac (T435-800T) as I drawn below. Is there any way to avoid isolated power supplies in such cases? Please let me know your opinion. Thanking you.   #triac #snubberless

Posted on November 16, 2017 at 09:47I see in the code#ifdef THREE_SHUNT  SVPWM_3ShuntInit(); #elif defined ICS_SENSORS SVPWM_IcsInit(); #elif defined SINGLE_SHUNT  SVPWM_1ShuntInit();  #endifBut in the code - SVPWM_3ShuntInit(); and SVPWM_1ShuntInit();  - both functions set three channels for current reading.So what difference between both methods?Actually the question is transformed - what is the preferable method?