Power management

Posted on April 21, 2016 at 22:26Hello, I am testing the L5491 Evaluation board and having problems getting the IGBTs to turn on. Currently I am using FGH60N60 IGBTs for controlling a light bulb. I have a microcontroller generating a 1kHz 5Vpp square wave and 4N25 optocoupler for isolation from high voltage. Here is an attached picture and schematic of my setup. http://imgur.com/T2fpoBf I am sure there is something very obviously missing and/or wrong about the setup. Hopefully you guys can point me in the right direction. Thanks, Eric

Posted on April 20, 2016 at 14:06Hi,I'm new bee here. My project needs to consume very less power. I see that STM32L053R8 consumes 88µA/MHZ that means it takes 88µA*16 for 16MHZ? or is it different?. I would like to perate my controller at 5MHZ only, Thank you.

Posted on April 18, 2016 at 21:49Hello, EVAL6480H uses very robust MOSFETs with hefty intrinsic diodes (25A pulsed current). Does this suggest that it would be ok in practice to exclude catch/snubber diodes from H-bridge design when employing the L6480, as long as within spec of the eval board?Or perhaps this is permissible strictly for microstepping mode (In full stepping mode and higher motor speeds, the transients from complete on/off switching must be far worse)? I would assume the eval board is built to showcase the 6480 in its best possible light (save for EMI perhaps)...but this seems risky for switch longevity, especially with the specs that this IC can support (Vmot, motor current, RPM, etc...).Also, which full-step drive mode does the L6480 use beyond microstepping mode threshold?Thanks in advance,Martin #eval6480h

Posted on March 17, 2016 at 11:26Dear all,we are noticing breakdown of SPV1040 in our implementation on a board for energy harvesting from solar panel. The breakdown is only for some board. Here you can see the configuration.The solar panel is a couple of mono crystalline silicon http://eshop.terms.eu/_data/s_3386/files/1379942540-sunpower_c60_bin_ghi.pdf in series configuration. For better performance in low-light condition, we introduce a 100nF capacitor in parallel to CINsns_2.When the c

Posted on April 14, 2016 at 08:29Hello, where can I find the spice model of L6598D? I really appreciate it and thanks in advance! Regards Ras #l6598d-spice-model-.subckt-.mod

Posted on April 14, 2016 at 08:08In the http://www.st.com/st-web-ui/static/active/en/resource/technical/document/application_note/DM00100185.pdf?sc=an4397 of SPV1050 evaluation board ISV020V1 the equation of MPPT ratio is given as MPPratio * Voc= (Vin * R3) / (R1+R2+R3) [p.12]. However, the http://www.st.com/st-web-ui/static/active/en/resource/technical/document/datasheet/DM00100984.pdf?sc=spv1050-datasheetgives MPPratio = R3 / (R2 + R3) [p.25].Quick test shows that value in datasheets matches values ISV020V1 produces. 

Posted on April 13, 2016 at 16:52Hi, I'm using PM8800A in isolated topologies, 5 Vout with synchronous rectification. I followed the directions of Application notes AN_2783 and used the STS26N33LLH6 transistor output from the transformer. The problem is that this transistor too hot, even if a wide copper layer is used. Has anyone encountered the same problem? Regards Andrea #pm8800

Posted on March 30, 2016 at 20:21 Anyone had any luck getting the example project compiled and running for the Nucleo-IHM001? The binaries work fine respectively in both 6step and FOC modes. However when the example provided with SPN7V1.0.0 is compiled and downloaded the motor justjumps arounderratically... ...\STNUCLEO_Motor_eval_kit\STM32CubeExpansion_SPN7_V1.0.0\Projects\Multi\Examples\MotorControl\MDK-ARM\STM32F302R8-Nucleo The jumpers are configured for 6step of course, andthe motor motor parameters appear to be correct in MC_SixStep_param.h- #define NUM_POLE_PAIRS 7 /*!< Number of Motor Pole pairs */ #define DIRECTION 0 /*!< Set motor direction CW = 0 and CCW = 1*/ #define TARGET_SPEED 3000 /*!< Target speed in closed loop control */ #define POTENTIOMETER 1 /*!< Enable (1)/Disable (0) the potentiometer */ #ihm001 #ihm001 #p-nucleo-ihm001

Posted on November 12, 2015 at 21:17When I send any get or set command from micro to L6470 via SPI, the L6470 always responds with the command byte sent by the micro. It should be either sending the MSB of the get data or a 0 byte for a set command . Can anyone help? I'm using mode 3 In case this isn't clear I'll get a specific example. After reset of system, micro sends Get Config byte of 0x38 and expects to receive 0x2E88. So once 0x38 is sent by micro, the micro sends 0 and expects to receive msb which is 0x2E. Instead the micro receives 0x38. Can anyone explain. Thanks!

Posted on April 13, 2016 at 11:48Hello, I am using the eval board EVAL6226QR that has the dual full bridge driver L6226Q on it. I am using it to drive a 40kHz train of pulses from IN1A to OUT1A (and IN2A to OUT2A). To minimize current consumption, I am controlling the Vs pin (that has 32V on it) by a window that goes HIGH for 500 microseconds, and LOW for 30 milliseconds. After few tests (sometimes, that happens after few days of proper operation), the HBRIDGE breaks down ! (there are high current peaks detected on my voltage generator higher than 1Amp !) This is the fifth EVAL6226QR that breaks down now ! Feeding Vs with continuous voltage does not cause the hbridge to break down (but it consumes 120mA which is too high) I looked carefully into the datasheet of the eval board and that of the chip, and I found only frequency characteristics for IN pins only (Vs is supposed to have a const

Posted on April 13, 2016 at 11:27Hallo..I am using L6205 in parallel connection mode for high current. I have attached a load resistance of 10ohm at output and the Supply voltage is 12 volt. The load resistance was drawing about 1.2Amp current and I was getting 10.3 Volt at the output pin. Why there is such a big drop across switch ? #l6205

Posted on April 13, 2016 at 10:22Need help with calculation parametrs for current regulator.Try to use AN1451. And can`t calculate Switching Frequency.How to know Toff parametr ?

Posted on April 12, 2016 at 01:21Hi ,Can you do FOC on a BLDC motor or only on PMSM ?ThanksImtiaz

Posted on March 30, 2016 at 09:14Useful tool, but when VN5Exxx family will be availble for simulation?

Posted on April 01, 2016 at 18:07Hello Members,I have recently started looking into designing an AC/DC converter with the rating as mentioned in the subject. I am looking into possible solutions or reference designs provided by ST for this purpose. My goal is to keep the design as small as possible using SMD components where possible. Overall until now I have seen many reference designs using Transformers and bridge rectifiers which certainly do the job but on the other hand they are way to big for embedded application. I would be thankful if anyone here could help me in this regard.Best regards,Owais. #power-supply

Posted on April 01, 2016 at 18:06Hello Members,I have recently started looking into designing an AC/DC converter with the rating as mentioned in the subject. I am looking into possible solutions or reference designs provided by ST for this purpose. My goal is to keep the design as small as possible using SMD components where possible. Overall until now I have seen many reference designs using Transformers and bridge rectifiers which certainly do the job but on the other hand they are way to big for embedded application. I would be thankful if anyone here could help me in this regard.Best regards,Owais. #power-supply

Posted on January 10, 2016 at 17:24Now that I have FOC working on the STM board and the STM ''power stage'' the next step is to move all this over to my own power stage and logic board. The CPU part can wait, so now I'm working on getting the nucleo to control my own power-stage. I cannot simply use the binary that works with the powerstage in the IHM001: My power stage has different logic level combinations for ''don't drive'', ''drive high'', ''drive-low''. Currently I don't have any overcurrent protection. I'll do that ''manually'' for now. (i.e. a low currentlimit on the lab powersupply, and when everything works I'll move to a LIPO battery that limits the current to 2kA at most. :-).... I'll blow up the powerstage if things go wrong in that case. ) Anyway, while re-configuring in the MC suite GUI I could not find a place to specify where the voltage feedback signals go. The IHM001 power stage has the signals

Posted on March 17, 2016 at 08:23Hi there,I have built my own circuits to drive a BLDC motor. So far I have managed to get an RC BLDC motor working quite smoothly in open loop. However my 1kW motor is not running good at all, it cgs at lows speed and locks up at high speeds. I am assuming since it has larger inertia hence in can only work in closed loop (i.e. with hall sensors)For more information and videos on my progress so far visits this linkhttps://endless-sphere.com/forums/viewtopic.php?f=3&t=70870Having said that I am struggling a bit to implement closed loop control. I have found this code which seems to be fine although it is not complete. Currently in the process of seeing what is happening via the datasheet. Th

Posted on January 18, 2016 at 16:37Dear all,i'm building an application using STM32F303 and FOC Library 4.1.We're using a custom board with three shunt topology.PWD is 16kHZ and the motor runs up to 26k rpm. I use hall sensors for the statup phase and the switch to sensorless mode. Everything worked like a charm until i atted some functions using DMA (one is used to write on an SD Card and the other is used to draw a bitmap stored in flash on a LCD controlled via FSMC).When thes functions are called the MCI_GetSTMState returna and error state and MCI_GetOccurredFaults returns .Does anybody have an idea of what can be the cause of this issue?

Posted on March 31, 2016 at 18:26Looking for the thermal resistance from Junction to Case for the L6725TR DC-DC converter. #l6725

Posted on March 31, 2016 at 15:28I'd like to know if the STL62P3LLH6 P-channel MOSFET's Safe Operating Area chart is correct in http://www.st.com/web/en/resource/technical/document/datasheet/DM00105886.pdfhttp://www.st.com/web/en/resource/technical/document/datasheet/DM00105886.pdf. I have been comparing these charts of various other parts, specifically the ID value at VDS = 20V and a 100ms pulse width. This part shows an ID of ~20A at this location. However, I've found no other parts with a value this high in a PowerFLAT package (or similar). All other parts with a value this high are DPAK (or similar, with a ~3x lower thermal resistance), and are quite a bit more

Posted on March 29, 2016 at 12:45Hi, I attached my schematic to help in my discussion.  I made a huge mistake by selecting a Linear Regulator U200: (12Vin - 5Vout).  Roughly I'm drawing about 1.5Amps, therefore my power dissipated across the IC is (12 - 5)(1.5) = 10Watts.  Yes, it overheats and always trips.The main input voltage to J200 is 5 - 42.  It connects to an LM25118 12Volt output regulator.  I made the decision to use the 12V design because I do need a 12 volt output on my board.  I'm using this same 12V output to feed U200 and U203.  I would like to replace U200 with perhaps a switching regulator to help with the power dissipation.  Other ideas are certainly welcome.  Designing to allow for unforeseen current draw is ok. I'm at the second spin on this board and clearly my customer is not happy.  Thanks,Brian

Posted on March 08, 2016 at 05:48Hi, I'm trying to build a constant current LED driver using the ST1CC40. I built a prototype version and noticed that with no load attached, the entire Vin (in my case its 12V) is seen at the output. Is this normal? In a situation where lets say the Vout is supposed to be 5V and the Vin is 12V, when the INH pin is pulled low, the Vout would be close to zero. However, when the INH is pulled high, would the Vout swing between Vin and Vout before stabilizing? In other words, would there be a massive spike in Vout? #st1cc40

Posted on March 28, 2016 at 07:43Hello! I want to ask a question about chip PFC L4984D.1. Calculate the inductor according to datasheet. When the input voltage is greater than 200 volts, the inductor begins to make noise, heavily distorted input current. By reducing the inductance, the noise becomes slightly less, but the PFC works in regime intermittent currents. The ideal characteristics are observed only when the minimum input voltage of 85 volts. What material should be used for PFC inductor? Tried X-Flux, High Flux, Kool mu. With Kool mu only managed to achieve more than acceptable results. What could be the problem?2. So it is unclear the frequency with which transformation occurs. According to Datasheet the chip operates with a fixed frequency (FOT). Set the capacitor for a frequency of 70 kHz, but the frequency does not match (is less than a set, and changes during the half cycle

Posted on March 25, 2016 at 14:04I am working on an application where I need to use three L6472 ICs on the same board. I am wondering what external components can be shared between 2 or 3 L6472's. For example, can one cap elec 100uf 63V on the VS inputs (as on your evaluation board) be shared between IC's? What about the charge pump caps and diodes for the VBoot? I am looking to reduce components and layout space as the total board size is restricted for this application. For information, the motor voltage will be 12V and the typical motor current will be less than 1 amp. Also only one motor will be running at any one time. Thanks for your help. Greg #l6472