Power management

Posted on June 07, 2012 at 15:05Hello all.I would like to receive some suggestions of ICs / considerations about this design.The picture below states how this power supply should work.http://e2e.ti.com/cfs-file.ashx/__key/communityserver-discussions-components-files/196/5460.PSU_5F00_01.pngDetails:1) IC 1 probably will be a LT3650-8.4 from Linear Technology. It supports up to 32V of input voltage (40V peak). Suggestions of other ICs for this purpose?2) The power supply INPUT has only two states: (A) Floating (cut-off) and (B) 17 to 30VDC present at the input.3) The OR'ing circuit at the OUTPUT, as the picture shows, doesn't mean it will be done with diodes. It can be done with MOSFETs, relays, or any kind of log

Posted on March 22, 2012 at 02:32Hi I have several different motors that I would like to drive (one at a time) using the same hardware and firmware based on the STM32 FOC PMSM libraries. The motor selection is indicated to the processor with a DIP switch so that the software can determine which motor is connected. The motors have different stator inductances, resistances and voltage constants so I need to change the dependent parameters C1 to C6 of the STO object. Does anybody have any suggestions of how this can be achieved? Thank you, Nick

Posted on May 16, 2012 at 06:08I have an application where i need to use Viper25H in non-isolated mode.For reference generation I am using TL431. But the problem is that when TL431 is used for non-isolated configuration , power supply is getting into burst mode operation. Can you please suggest  a reference circuit for using TL431 in non-isolated configuration specifically for Viper25H. The same configuration if used using Opto-coupler its working fineAs Viper25 does not have in it a error amplifier so i cannot used a simple resistor divider.Using a zener based solution will have more impact on its temperature based tolerances.So i have to use TL431 in feedback loop but using it for non isolated configuration is a bit of trick. Please suggest its urgent

Posted on April 28, 2012 at 08:56Hi all, I got a 200 Watt Resonant SMPS board based on L6599 (STEVAL-ISA018V1) and wanted to  simulate it with the eDesignSuite but I couldn't find a L6599 design. It seems that there are no eDesigns for the L6599 available. Are there any SPICE models for the L6599 available or how should I simulate this design? #l6599

Posted on April 11, 2012 at 16:34Hello, I'm a bit confused about the timer usage for the Hall sensors on the STM3210B-EVAL board. The encoder signals (which are used for the hall signals too) are placed on the GPIOs PA0, PA1 and PA2 and timer TIM2 is used. The problem is, that on page 41 of the user manual, the pin PA2 is connected to MC_TIM4_CH3, thus TIM4, and NOT TIM2. Is for this evaluation board, more than one timer for the hall signals used?? I want to run a simple, self made block commutation example using one PWM Timer and one HALL timer, which already runs on a STM3210E-EVAL board. regards, sebastian

Posted on April 10, 2012 at 02:44The new eDesignstudio does not support the VIPER53E. Original design was done by software supported by ST, but can not find it on the web. Can you send me or point me to where I can get a copy?

Posted on March 19, 2012 at 10:50Hi everybody On my simple Cw, Ccw control, for low power brushed d.c. motors, realized around L6207, i need to adjust the motor's speed. Is it a good idea to Pulse Width  modulate the enable input (EA) instead using it just at purpose? I am little bit afraid to fall in beating problems with pwm current control. I'm considering the possibilty to devolope a new project, any suggestion about a more suitable chip? Thank a lot for helps Alfredo

Posted on March 20, 2012 at 18:09Hi! I have some questions about L6470 decoupling and voltage tolerance.1. If I use an external 3.3v to drive both Vreg and Vdd (internal reg disabled), do I still need a 40uf Vreg cap or I can use just one 10uf?2. Can I use Vs bulk capacitor with lover value but better ESR? ESR and Ripple current is primary parameters for Vs bulk cap, am I right?3. Is the SW pin still 5v tolerant when external Vreg = Vdd = 3.3v?Thanks, Iurie #l6470

Posted on January 06, 2012 at 10:09Hello,I want to execute my project with HVLED805 where input voltage is 176…264 V.Output voltage for LED equal 18 V, output current 0.45 A.Edesign proposed the transformer with widings: Primary – 145 turns, Aux – 29 turns, Secondary – 34 Turns, transformer core EE16, Reflected voltage 80 V.I can’t allocate these winding therefore in program VIPer Design Software v.2.24 I have counted analogous transformer with widings: Primary – 120 turns, Aux – 17 turns, Secondary – 20 Turns, transformer core EE16, Reflected voltage 115 V.Edesign recommended Rsense=0.931 ohm.For calculation of this parameter with the new transformer I have used the equation (7) of datasheet (Off–line LED driver with primary–sensing HVLED805 -

Posted on March 05, 2012 at 16:38STM3210E eval board has a stm32103ZG MCU  on it and this MCU resides in  XL-density group. The problem is related with ST motor control workbench. It has no option to generate header files for XL density devices under Control stage>MCU and clock Frequency.Available options are :Performance line High densityPerformance line Medium densityPerformance line Low densityValue Line Medium densityValue Line Low densityHow can i generate related headers for the 103ZG MCU via motor control workbench tool.Regards.

Posted on February 08, 2012 at 15:30Hallo, is it possible to drive two motors with this eval board? I don't want to drive them simultaneously and independently but ''mutual exclusive'', i.e. I have one enable signal for every motor, while only one is true at a time. On the uC only one control function is running at any time. Just using a Y-cable from the MC connector to two power stages wouldn't work, as I have no possibility to disable one of the two motors, right? On the other hand, is it possible to connect some GPIOs to a second power stage to do real dual drive simultaneously? (This would be some kind of a second MC connector which doesnt exist on my board). thanks in advance. regards, sebastian

Posted on February 15, 2012 at 01:24Hi, I'm working with the PMSM firmware library V3.0 to make a motor control using the STM32F103C8T6 processor operating on my own board. I am working with the provided non-RTOS project which was originally configured for the STM3210B-EVAL board. I have the problem that timer 1 apears to be remapped (AFIOMAPR:TIM1_REMAP = 0x3) regardless of definition: #define PWM_TIMER_REMAPPING               PWM_NO_REMAP in the Control stage parameters.h file. Edit: Problem solved by using the Batch build option to re-compile the motor control code instead of just Download and Debug which only recompiles the user project. Thank you Nick

Posted on February 06, 2012 at 08:46Where I can find the schematics source files  of the STM32f4discovery board ? #schematics

Posted on January 24, 2012 at 08:01Hi We want to overclock the L6470 (10MHz instead of 8MHz at OSCIN) to increase maximum RPM. The resolution will be reduced, this is clear, but is there any other risk to do so? Regards Michael

Posted on December 22, 2011 at 15:03HiWe have measured the output signals of the bridges in 1/128 and 1/32 step mode and we can’t see a different voltage resolution between these 2 modes (see attachment). We have used the “GoToâ€�-command for the positioning, and mostly we can see a repositioning of the motor after the 4th step only in the 1/128-step mode (what  confirms with the measured values). Is there any limitation of the output resolution? Best RegardsMichael

Posted on August 18, 2011 at 21:35L6470: connect Vreg and Vdd for 5V supply? #l6470 #l6470

Posted on November 08, 2011 at 11:01In my design iam using Viper25DTH. My o/p power is upto 6W i.e. 4.1V@1.5A. But whenevr i am ging 1W load, the voltage on VDD pin starts to oscillate between 4.5V to 15V and feedback voltage is upto 3.4v, it seems that OLP protection is on at this stage. I have selected Rlimt=18K                         Rovp=100K                        Rff=1000K I  have done many iterations to achieve o/p but invain. Please suggest #urgent

Posted on December 26, 2011 at 13:35Hello.When activating the brake option I get the following error. ''ID211 brake resistor switch off threshold voltage Higher Than over-threshold'' Dissipative brake checked and active high. Min rated voltage 18V Max rated voltage 32V Nominal voltage 22V at sensing Enabling and firmware protection. enable overvoltage threshold voltage over 32V on over voltage switch on brake resistor. I think that limit is in this parameter. Ther

Posted on April 15, 2010 at 10:13We are using the L6920 to drive a 1 watt LED. We are trying to implement the under voltage cut off (lock out) too. We chose the values of the voltage bridge connected to the LBI pin such that the value comes to say 3V. However, the IC did not shut off at 3V. We then tried connecting the LBO to Vout with a 200K resistor in between. Even this did not work. Can someone help implement this circuit? Thanks! Ashish #led-backlighting-power-supply

Posted on December 06, 2011 at 08:58HelloWe’re currently testing the possibility of using the L6470. It’s working well in full rotation with using the “Runâ€�-command. Additional, we want to perform a ±pos mode with intermediate points and a defined speed between the positions. The “GoToâ€�-command seems to be the right one for this job, but the resolution of MaxSpeed, which is used by this command, is too bad. Is there any way to use speed in the resolution of 2^20 like the “Runâ€� or “GoUntilâ€�-commands? Best regards Michael

Posted on December 07, 2011 at 15:03Hi, Im completely new to the topic of motor control with STM32 devices. To get started, I chose the STM3210E-EVAL board, the STEVAL-IHM031V1 driver board and an appropriate BLDC. Now Im trying to generate the parameter headers and sources with the motor control workbench matching my hardware. The problem is, that I can't find all neccessary parameters for the power stage, e.g. temperature sensing, params of the MOSFET power switches (dead-time, switching frequency) ... to name but a few. Neither the user manuals of the boards nor the data sheets of the particular components contain these parameters. Where can I get them? thanks in advance! regards, sebastian

Posted on December 09, 2011 at 17:03Hello The motor kit comes with the motor MCKIT LA052-080E3NL1 Shinano. Phase 0.60 ohm resistance Inductance 1.4 mH Phase Back EMF constant Kv 6.2 / krpm However, in the motor parameter ''workbench motor control'' sets. Motor winding resistance RS (phase) 0.35 ohm Synchronous Motor winding inductance Ls (phase) 0.6mH B-EmfConstant (Vrms / krpm) 4 kv / krpm I would need an explanation of the conversion performed. Best regards

Posted on December 07, 2011 at 11:00Hello I need to decelerate a motor on a closed loop speed (no braking free). The system should reduce the duty cycle and finally implement a change of quadrant motor. Is the library prepared to decelerate  the motor in closed loop (four quadrant)? At the documentation the motor is always in wye connection. Is the library prepared to control a motor at delta configuration? Would it change the parameters Rs and Ls used by the software ''workbench st motor control''? And another parameters? Best rega

Posted on November 19, 2011 at 02:42Hello,I have my encoder A and B channel signal connected to PB10 & PB11. This is TIM2 CH3 and TIM2 CH4. My question is: is it possible to run Encoder interface mode on CH3 & CH4, because i see, there is only CH1 and CH2 in datasheet?My uC is STM32F103RC. #encoder

Posted on December 07, 2011 at 10:34Hello I am using ''ACIM and BLDC motor control firmware library V1.0'' BLDC motor and a hall sensor. In closed loop speed when the motor decelerates the system reduces the duty cycle. Finally, there is no PWM signal and the motor slows down freely. Is the library prepared to stop the motor in closed loop (Four-Quadrant)? Best regards