Power management

Hello ST Community, i have problems to get the VNF1048F chip to run. It goes every time to the fault state and can not find out, why this problem occurs.The documentation for this chip is not really good and there is not sample application (Source Code) where i can look to find a solution for this problem. Does anyone have some sort of source code how to implement a sequence that this chip is working? I would appreciate any kind of help, to get this VNF1048 chip running.Thank you very much and best regards, Markus

Hello, We are developing a design around VNF1048F & VNF1248F products.  We are considering a multichannel design with different output settings. In a multichannel design, naturally we are expecting to have control and monitoring capability of individual channels. We would like to know if the SPI and Diagnostic functions are accessible if we disable VS supply (with external main switches). Basically, we want to disable the outputs and monitor or control the channels to see which one is broken. One absurd idea that we are thinking is that we could supply V3V3 pin (internal LDO output) with external 3V3 source to keep logic awake but we are not sure if it will damage the IC or if it will work. Could you please let us know if this is possible? Thanks.  

Hello,We are developing a design around VNF1048F & VNF1248F products. From the other community posts, we learned that VNF1048F has ASIL - B for functional safety rating.We would like to confirm this information, and we also would like to know if VNF1248F has any functional safety capability.Can you also share the related safety documentation for both devices?Thanks.

Hello I am using the L6494(14PIN) as a driver for a high and low side FET in a half bridge arrangement. My DC volts can be anything from 120Vdc to 220Vdc. and current up to 17AIs there anyway to determine the breakdown mechanism if I do not momentarily switch the bottom driver on to charge the bootstrap capacitor.?If I do not switch the bottom driver on first so that the bootstrap capacitor is charged and accadently turn the top driver on first, it destroys the driver and fets. I have wired in the L6498 (8PIN) and this does not behave the same way. I can always make sure of the sequence under normal conditions but under a fault condition this could not be guaranteed and an expensive call out could follow.Is there possibly another way to guarantee the bootstrap capacitor gets charged ? thanks 

EVLVIPGAN65DF application note states that the provided reference design is compliant with IEC55022 Class B conducted EMI. How about radiated EMI? Is there any measurement in this regard? 

Hi,We're encountering an issue with the L6982CDR buck converter in our application. Here's the detailed scenario: Configuation: We're using it to convert a 24V input to a 5V output to power the board. Load: The 5V output supplies a load current of approximately 200mA. System Context: The same 24V input is also used to drive a stepper motor. Problem:Following mass production, some units have experienced a loss of the 5V output. The occurrence rate of this failure is low. Key Observations: This fault occurs during operation, not at power-up. The fault clears if the 24V power is restarted. When the failure happens, we measured a normal 24V input voltage and a normal voltage at the VCC pin of the IC. However, the SW pin output remains low. Notably, we have used this chip reliably for a long time, and this is a recent issue.Here is the schematic of our product：

Please help finding what diode is this, picture attached, the marking looks like 6BD, Thank you for any help provided.

I don't know what happened recently (or perhaps longer) with the ST website, but where can I find the ST products?

Greetings, I have being searching for this diode but I had no luck. Markings: BEX 6BA (SG)?)This is an electronic control module (ECM) 12v for an ATV 2007 Polaris 450. I am trying to fix it and I need help to buy this little piece. Any help will be appreciated.Thank you.

Dear ST Community Members,I have built a 7KW three-phase interleaved totem pole PFC circuit (based on the schematic of STEVAL-7BIDIRCB, retaining only the PFC section). The firmware was generated using ST eDesignSuite's "FW download" tool. Before power-up, I verified the ADC readings for input voltage/current and output voltage/current sampling, all of which matched the calculated values.Current Observations:Scenario A:Apply 230V/50Hz AC power first → Power on the STM32G474 MCUResult: Output stabilizes at 325V (rectified voltage), control board yellow LED lights up, and can't start.Scenario B:Power on the STM32G474 MCU first → Apply 230V/50Hz AC powerResult: Output rises from 0V to 230V, holds for ~300ms, then the circuit breaker trips.Additional Notes:Trippin

 Hello everyone,we are currently trying to bring up the L6591 without PFC, but unfortunately we have not been successful so far.It looks like the L6591 is not able to start up correctly.The Vcc voltage slowly rises to about 14V with the built-in HV startup generator. The LINE pin is connected to Vcc through a 330kΩ resistor, and after a short time it rises above 1.25V, as expected. So in principle all startup conditions for the L6591 should be fulfilled.After that, the SS pin charges to 2V, VREF reaches 5V, and then the IC repeatedly restarts. We are not sure why this happens.Is there any additional documentation available that explains the startup sequence in more detail? The information in the datasheet is not completely clear to us. Unfortunately, we currently have no evaluati

I am selecting the LD1117S50CTR. The package is SOT-223.I understand that the thermal resistance Rthja = 110 °C/W shown in the datasheet is the value for the IC alone.Since I am designing the PCB, I would like to know the relationship between copper area and thermal resistance.I would appreciate your advice.

Translator         I would like to identify the following two diodes, please.

Hello, The datasheet doesn't seem to mention the function the tab on the back of the IC. Can I connect it to GND to thermally conduct the heat out?  Thanks

Hello! I am designing a wide input range flyback converter using the altair04-900 for my formula student team.For testing the switching behaviour, I simulated the ALTAIR04-900 using the schematics in the datasheet of figure 4-7. figure 4-6 shows results comparable with the values specified on the datasheet- with Idss(off) being 104uA instead of 80uA. Simulating figure 7 I made the following assumption: the IC should actually switch. My reasoning: Icc has the value of the operating current as stated in the datasheet. However the simulation results show discrepancies (reference see „simfigure7“); Icc has the expected value, but voltage at ZCD never goes above arming threshhold, therefore the IC should not be able to switch. My explanation: Some kind of brown-out, as Vzcd is below the internal clamping voltage as stated in the datasheet. Also notable: Vdc above 2.79V on COMP pin gives a converging error. Instead, I used a close value of 2.79Vdc. For further testing I altered fig

Hi ST Micro,Please send me the information for the adjustable LDO output voltage desgined from R1 and R2 formula.

I cannot see the effect of the low speed optimization.I set speed to 1 rpm and watch the phase currents.With these settings (these values are readbacks):min_speed: 0x1fdfconfig: 0x2c90step_mode: 0x0007I get significant distortion around 0 A:To compare, with min_speed == 0 (so LSPD_OPT off):

The PowerSTEP01's datasheet says on page 34 that MIN_SPEED is 12 bits wide.On page 37, it is described as 13 bits wide.I suppose that 13 is correct, from code I've read online, but a confirmation (and fix) would be nice. I cannot see the low speed optimization have any effect whatsoever on my phase currents, running from 1 rpm (even lower), to around 8 rpm, where the optimization doesn't seem needed anyway. Any help on how to fix it would be appreciated (running with MIN_SPEED to 0x00 or 0x1fdf, does not affect the current wave at 1 rpm).

Hello Team,We have selected part no: LDK220 and LDK320 with a SOT-89 footprint for one of our applications. We have referred to the complete datasheet, but we have not found the test results for 5V output category devices, like the voltage dropout of 5V 100mA with all operating temperature ranges. Can you please provide the document or suggest any section where this kind of test results are available for reference? Awaiting your reference!ThanksJayjit Y

I've been looking at the STEVAL-ISD01KCB, and I saw in an image that it has some capacitors between pins 8 (-DC) and 9 (+DC). What is the value of that capacitor? Is it necessary to include it? I ask because I've noticed that this capacitor slightly reduces the distance between the -DC and +DC pins.

 I have  design Buck  converter with Viper318HD ,With below specification:Vin:(85 to 265)VACVout=12VDCIout=500mAAnd i not follow recommended   Commponents   value  which  Are mentioned in Edesign tool,  i use  components which  are availble  with me.So  i need:1- Know is this  design  will  be stable  to use it  or not ??  

I have a design running on 24V SLA batteries using STEF01 fuses for protection of the lower powered rails and an LT4356 using external MOSFETs for a 25Amp rail. That 25A rail is giving me headaches. Staying within the SOA of the MOSFETs is not that easy when the output is started up shorted, and even though it works on the bench it fails from time to time in the field. The STEF01 fuses  have been performing flawlessly. Now, the load on the 25A line is a parallel wound DC motor and an external motor controller. The field winding is powered directly from the 25A line, the armature is powered by external electronics which takes some time to power up. Thus, the load on the 25A line is both a large capacitance (external electronics input capacitance; 3000+uF) parallel to a large inductor (oh joy. Yes, I do have transient voltage limiting..). I cannot change this arrangement.  I wonder if I could parallel 5 or 6 STEF01 fuses

Hello, (L6562DTR)I have encountered some problems when using this chip and hope to get some suggestions from you；  ”The PF output voltage of 480V FC load is 0.7435“   The power input voltage is 250V-528VAC, with PFC+ flyback. The PFC BUS voltage is 760V, and the power output is 150W；When the input is 480VAC and the output is fully loaded, the THD is abnormal, ranging from 10% to 20% (5% for normal products), and at the same time, the PF value also drops and there is noise from the power supply How can this problem&

Looking for datasheets for the STWBC2HP and STWLC89, do these exist? I can't find them anywhere on the internet

Hello Everybody, I'm new in this place. I use an Evalboard ISC005V1 with STUSB4500 and an dedicate MCU to manage I²C port. I wanted to change the configuration of the PDO3 from 20V to 15V. I select PORT3 ( write 3 in 0x70 register ) I configure DPM_REQ_RDO3 register ( adress 0x91 )  with 0x96, 0xB0, 0x04 and 0x00. I soft reset the STUS4500  But nothing change. VBUS and PDO3 out still 20V???   What's wrong Thanks for the help!